From a5f7a5bb3b7f28ba7e4fa246775b29a0e5537255 Mon Sep 17 00:00:00 2001
From: Jinke Han <jinkehan@didiglobal.com>
Date: Tue, 8 Sep 2026 15:37:42 +0800
Subject: x86/kprobes: Fix crash when probing CS CALL instructions

When using eBPF to probe CS CALL instructions within a function,
a crash can be triggered.

The eBPF tool probes offset 257 of the __hrtimer_run_queues()
function:

<__hrtimer_run_queues+249>:  nopl   0x0(%rax,%rax,1)
<__hrtimer_run_queues+254>:  mov    %r14,%rdi
<__hrtimer_run_queues+257>:  cs call <__x86_indirect_thunk_r12>
<__hrtimer_run_queues+263>:  mov    %eax,%r12d
<__hrtimer_run_queues+266>:  xchg   %ax,%ax
<__hrtimer_run_queues+268>:  mov    %r13,%rdi

Which triggers this crash:

  BUG: unable to handle page fault for address: 00000000000f41c9
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD 0 P4D 0
  Oops: 0002 [#1] SMP NOPTI
  CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P
  RIP: 0010:__hrtimer_run_queues+0x106/0x230

Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is
at the 6th byte of the above CS CALL instruction. Since the CS CALL
instruction occupies 6 bytes, the exception occurred in the middle of that
call instruction.

The root cause is that when using eBPF tools to probe in the middle of a
function, a kprobe with INT3 is used as the underlying implementation.

During single-step emulation of the original CALL instruction,
int3_emulate_call() assumes that the probed CALL instruction is 5 bytes
long. However, the actual CS-prefixed CALL instruction occupies 6 bytes,
so it constructs an incorrect exception return address. When the CPU
returns from the kprobe handler, the next instruction to be executed is at
the address of the last byte of that CS CALL instruction. Coincidentally,
starting from that address, the CPU fetches and decodes a completely
different instruction, which ultimately triggers a kernel crash.

Fix the issue by using the actual instruction length obtained from
the instruction decoder when constructing the exception return
address, rather than relying on the hardcoded CALL_INSN_SIZE macro.

[ mingo: Refined the changelog ]

Fixes: 6256e668b7af ("x86/kprobes: Use int3 instead of debug trap for single-step")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Jinke Han <jinkehan@didiglobal.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://patch.msgid.link/20260908073742.GA10517@didi-ThinkCentre-M920t-N000
---
 drivers/gpu/drm/stm/Kconfig           |   35 +
 drivers/gpu/drm/stm/Makefile          |   10 +
 drivers/gpu/drm/stm/drv.c             |  273 +++++
 drivers/gpu/drm/stm/dw_mipi_dsi-stm.c |  800 +++++++++++++
 drivers/gpu/drm/stm/ltdc.c            | 2116 +++++++++++++++++++++++++++++++++
 drivers/gpu/drm/stm/ltdc.h            |   71 ++
 drivers/gpu/drm/stm/lvds.c            | 1228 +++++++++++++++++++
 7 files changed, 4533 insertions(+)
 create mode 100644 drivers/gpu/drm/stm/Kconfig
 create mode 100644 drivers/gpu/drm/stm/Makefile
 create mode 100644 drivers/gpu/drm/stm/drv.c
 create mode 100644 drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
 create mode 100644 drivers/gpu/drm/stm/ltdc.c
 create mode 100644 drivers/gpu/drm/stm/ltdc.h
 create mode 100644 drivers/gpu/drm/stm/lvds.c

(limited to 'drivers/gpu/drm/stm')

diff --git a/drivers/gpu/drm/stm/Kconfig b/drivers/gpu/drm/stm/Kconfig
new file mode 100644
index 000000000..635be0ac0
--- /dev/null
+++ b/drivers/gpu/drm/stm/Kconfig
@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config DRM_STM
+	tristate "DRM Support for STMicroelectronics SoC Series"
+	depends on DRM && (ARCH_STM32 || COMPILE_TEST)
+	depends on COMMON_CLK
+	select DRM_CLIENT_SELECTION
+	select DRM_KMS_HELPER
+	select DRM_GEM_DMA_HELPER
+	select DRM_PANEL_BRIDGE
+	select VIDEOMODE_HELPERS
+	select FB_PROVIDE_GET_FB_UNMAPPED_AREA if FB
+
+	help
+	  Enable support for the on-chip display controller on
+	  STMicroelectronics STM32 MCUs.
+	  To compile this driver as a module, choose M here: the module
+	  will be called stm-drm.
+
+config DRM_STM_DSI
+	tristate "STMicroelectronics specific extensions for Synopsys MIPI DSI"
+	depends on DRM_STM
+	select DRM_DW_MIPI_DSI
+	help
+	  Choose this option for MIPI DSI support on STMicroelectronics SoC.
+
+config DRM_STM_LVDS
+	tristate "STMicroelectronics LVDS Display Interface Transmitter DRM driver"
+	depends on DRM_STM
+	help
+	  Enable support for LVDS encoders on STMicroelectronics SoC.
+	  The STM LVDS is a bridge which serialize pixel stream onto
+	  a LVDS protocol.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called lvds.
diff --git a/drivers/gpu/drm/stm/Makefile b/drivers/gpu/drm/stm/Makefile
new file mode 100644
index 000000000..ad740d617
--- /dev/null
+++ b/drivers/gpu/drm/stm/Makefile
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+stm-drm-y := \
+	drv.o \
+	ltdc.o
+
+obj-$(CONFIG_DRM_STM_DSI) += dw_mipi_dsi-stm.o
+
+obj-$(CONFIG_DRM_STM_LVDS) += lvds.o
+
+obj-$(CONFIG_DRM_STM) += stm-drm.o
diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
new file mode 100644
index 000000000..0967b9b34
--- /dev/null
+++ b/drivers/gpu/drm/stm/drv.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Mickael Reulier <mickael.reulier@st.com>
+ */
+
+#include <linux/aperture.h>
+#include <linux/component.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <drm/clients/drm_client_setup.h>
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fbdev_dma.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_module.h>
+#include <drm/drm_print.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+#include <drm/drm_managed.h>
+
+#include "ltdc.h"
+
+#define STM_MAX_FB_WIDTH	2048
+#define STM_MAX_FB_HEIGHT	2048 /* same as width to handle orientation */
+
+static const struct drm_mode_config_funcs drv_mode_config_funcs = {
+	.fb_create = drm_gem_fb_create,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static int stm_gem_dma_dumb_create(struct drm_file *file,
+				   struct drm_device *dev,
+				   struct drm_mode_create_dumb *args)
+{
+	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
+
+	/*
+	 * in order to optimize data transfer, pitch is aligned on
+	 * 128 bytes, height is aligned on 4 bytes
+	 */
+	args->pitch = roundup(min_pitch, 128);
+	args->height = roundup(args->height, 4);
+
+	return drm_gem_dma_dumb_create_internal(file, dev, args);
+}
+
+DEFINE_DRM_GEM_DMA_FOPS(drv_driver_fops);
+
+static const struct drm_driver drv_driver = {
+	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
+	.name = "stm",
+	.desc = "STMicroelectronics SoC DRM",
+	.major = 1,
+	.minor = 0,
+	.patchlevel = 0,
+	.fops = &drv_driver_fops,
+	DRM_GEM_DMA_DRIVER_OPS_WITH_DUMB_CREATE(stm_gem_dma_dumb_create),
+	DRM_FBDEV_DMA_DRIVER_OPS,
+};
+
+static int drv_load(struct drm_device *ddev)
+{
+	struct platform_device *pdev = to_platform_device(ddev->dev);
+	struct ltdc_device *ldev;
+	int ret;
+
+	DRM_DEBUG("%s\n", __func__);
+
+	ldev = drmm_kzalloc(ddev, sizeof(*ldev), GFP_KERNEL);
+	if (!ldev)
+		return -ENOMEM;
+
+	ddev->dev_private = (void *)ldev;
+
+	ret = drmm_mode_config_init(ddev);
+	if (ret)
+		return ret;
+
+	/*
+	 * set max width and height as default value.
+	 * this value would be used to check framebuffer size limitation
+	 * at drm_mode_addfb().
+	 */
+	ddev->mode_config.min_width = 0;
+	ddev->mode_config.min_height = 0;
+	ddev->mode_config.max_width = STM_MAX_FB_WIDTH;
+	ddev->mode_config.max_height = STM_MAX_FB_HEIGHT;
+	ddev->mode_config.funcs = &drv_mode_config_funcs;
+	ddev->mode_config.normalize_zpos = true;
+
+	ret = ltdc_load(ddev);
+	if (ret)
+		return ret;
+
+	drm_mode_config_reset(ddev);
+	drm_kms_helper_poll_init(ddev);
+
+	platform_set_drvdata(pdev, ddev);
+
+	return 0;
+}
+
+static void drv_unload(struct drm_device *ddev)
+{
+	DRM_DEBUG("%s\n", __func__);
+
+	drm_kms_helper_poll_fini(ddev);
+	drm_atomic_helper_shutdown(ddev);
+	ltdc_unload(ddev);
+}
+
+static __maybe_unused int drv_suspend(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct drm_atomic_commit *state;
+
+	WARN_ON(ldev->suspend_state);
+
+	state = drm_atomic_helper_suspend(ddev);
+	if (IS_ERR(state))
+		return PTR_ERR(state);
+
+	ldev->suspend_state = state;
+	pm_runtime_force_suspend(dev);
+
+	return 0;
+}
+
+static __maybe_unused int drv_resume(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+	struct ltdc_device *ldev = ddev->dev_private;
+	int ret;
+
+	if (WARN_ON(!ldev->suspend_state))
+		return -ENOENT;
+
+	pm_runtime_force_resume(dev);
+	ret = drm_atomic_helper_resume(ddev, ldev->suspend_state);
+	if (ret)
+		pm_runtime_force_suspend(dev);
+
+	ldev->suspend_state = NULL;
+
+	return ret;
+}
+
+static __maybe_unused int drv_runtime_suspend(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+
+	DRM_DEBUG_DRIVER("\n");
+	ltdc_suspend(ddev);
+
+	return 0;
+}
+
+static __maybe_unused int drv_runtime_resume(struct device *dev)
+{
+	struct drm_device *ddev = dev_get_drvdata(dev);
+
+	DRM_DEBUG_DRIVER("\n");
+	return ltdc_resume(ddev);
+}
+
+static const struct dev_pm_ops drv_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(drv_suspend, drv_resume)
+	SET_RUNTIME_PM_OPS(drv_runtime_suspend,
+			   drv_runtime_resume, NULL)
+};
+
+static int stm_drm_platform_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct drm_device *ddev;
+	int ret;
+
+	DRM_DEBUG("%s\n", __func__);
+
+	ret = aperture_remove_all_conflicting_devices(drv_driver.name);
+	if (ret)
+		return ret;
+
+	dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
+
+	ddev = drm_dev_alloc(&drv_driver, dev);
+	if (IS_ERR(ddev))
+		return PTR_ERR(ddev);
+
+	ret = drv_load(ddev);
+	if (ret)
+		goto err_put;
+
+	ret = drm_dev_register(ddev, 0);
+	if (ret)
+		goto err_unload;
+
+	drm_client_setup_with_fourcc(ddev, DRM_FORMAT_RGB565);
+
+	return 0;
+
+err_unload:
+	drv_unload(ddev);
+err_put:
+	drm_dev_put(ddev);
+
+	return ret;
+}
+
+static void stm_drm_platform_remove(struct platform_device *pdev)
+{
+	struct drm_device *ddev = platform_get_drvdata(pdev);
+
+	DRM_DEBUG("%s\n", __func__);
+
+	drm_dev_unregister(ddev);
+	drv_unload(ddev);
+	drm_dev_put(ddev);
+}
+
+static void stm_drm_platform_shutdown(struct platform_device *pdev)
+{
+	drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
+}
+
+static struct ltdc_plat_data stm_drm_plat_data = {
+	.pad_max_freq_hz = 90000000,
+};
+
+static struct ltdc_plat_data stm_drm_plat_data_mp25 = {
+	.pad_max_freq_hz = 150000000,
+};
+
+static const struct of_device_id drv_dt_ids[] = {
+	{ .compatible = "st,stm32-ltdc", .data = &stm_drm_plat_data, },
+	{ .compatible = "st,stm32mp251-ltdc", .data = &stm_drm_plat_data_mp25, },
+	{ .compatible = "st,stm32mp255-ltdc", .data = &stm_drm_plat_data_mp25, },
+	{ /* end node */ },
+};
+MODULE_DEVICE_TABLE(of, drv_dt_ids);
+
+static struct platform_driver stm_drm_platform_driver = {
+	.probe = stm_drm_platform_probe,
+	.remove = stm_drm_platform_remove,
+	.shutdown = stm_drm_platform_shutdown,
+	.driver = {
+		.name = "stm32-display",
+		.of_match_table = drv_dt_ids,
+		.pm = &drv_pm_ops,
+	},
+};
+
+drm_module_platform_driver(stm_drm_platform_driver);
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
+MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
new file mode 100644
index 000000000..a3eae5b2c
--- /dev/null
+++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
@@ -0,0 +1,800 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/bridge/dw_mipi_dsi.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_print.h>
+
+#define HWVER_130			0x31333000	/* IP version 1.30 */
+#define HWVER_131			0x31333100	/* IP version 1.31 */
+
+/* DSI digital registers & bit definitions */
+#define DSI_VERSION			0x00
+#define VERSION				GENMASK(31, 8)
+
+/* DSI wrapper registers & bit definitions */
+/* Note: registers are named as in the Reference Manual */
+#define DSI_WCFGR	0x0400		/* Wrapper ConFiGuration Reg */
+#define WCFGR_DSIM	BIT(0)		/* DSI Mode */
+#define WCFGR_COLMUX	GENMASK(3, 1)	/* COLor MUltipleXing */
+
+#define DSI_WCR		0x0404		/* Wrapper Control Reg */
+#define WCR_DSIEN	BIT(3)		/* DSI ENable */
+
+#define DSI_WISR	0x040C		/* Wrapper Interrupt and Status Reg */
+#define WISR_PLLLS	BIT(8)		/* PLL Lock Status */
+#define WISR_RRS	BIT(12)		/* Regulator Ready Status */
+
+#define DSI_WPCR0	0x0418		/* Wrapper Phy Conf Reg 0 */
+#define WPCR0_UIX4	GENMASK(5, 0)	/* Unit Interval X 4 */
+#define WPCR0_TDDL	BIT(16)		/* Turn Disable Data Lanes */
+
+#define DSI_WRPCR	0x0430		/* Wrapper Regulator & Pll Ctrl Reg */
+#define WRPCR_PLLEN	BIT(0)		/* PLL ENable */
+#define WRPCR_NDIV	GENMASK(8, 2)	/* pll loop DIVision Factor */
+#define WRPCR_IDF	GENMASK(14, 11)	/* pll Input Division Factor */
+#define WRPCR_ODF	GENMASK(17, 16)	/* pll Output Division Factor */
+#define WRPCR_REGEN	BIT(24)		/* REGulator ENable */
+#define WRPCR_BGREN	BIT(28)		/* BandGap Reference ENable */
+#define IDF_MIN		1
+#define IDF_MAX		7
+#define NDIV_MIN	10
+#define NDIV_MAX	125
+#define ODF_MIN		1
+#define ODF_MAX		8
+
+/* dsi color format coding according to the datasheet */
+enum dsi_color {
+	DSI_RGB565_CONF1,
+	DSI_RGB565_CONF2,
+	DSI_RGB565_CONF3,
+	DSI_RGB666_CONF1,
+	DSI_RGB666_CONF2,
+	DSI_RGB888,
+};
+
+#define LANE_MIN_KBPS	31250
+#define LANE_MAX_KBPS	500000
+
+/* Sleep & timeout for regulator on/off, pll lock/unlock & fifo empty */
+#define SLEEP_US	1000
+#define TIMEOUT_US	200000
+
+struct dw_mipi_dsi_stm {
+	void __iomem *base;
+	struct device *dev;
+	struct clk *pllref_clk;
+	struct clk *pclk;
+	struct clk_hw txbyte_clk;
+	struct dw_mipi_dsi *dsi;
+	struct dw_mipi_dsi_plat_data pdata;
+	u32 hw_version;
+	int lane_min_kbps;
+	int lane_max_kbps;
+	struct regulator *vdd_supply;
+};
+
+static inline void dsi_write(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 val)
+{
+	writel(val, dsi->base + reg);
+}
+
+static inline u32 dsi_read(struct dw_mipi_dsi_stm *dsi, u32 reg)
+{
+	return readl(dsi->base + reg);
+}
+
+static inline void dsi_set(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 mask)
+{
+	dsi_write(dsi, reg, dsi_read(dsi, reg) | mask);
+}
+
+static inline void dsi_clear(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 mask)
+{
+	dsi_write(dsi, reg, dsi_read(dsi, reg) & ~mask);
+}
+
+static inline void dsi_update_bits(struct dw_mipi_dsi_stm *dsi, u32 reg,
+				   u32 mask, u32 val)
+{
+	dsi_write(dsi, reg, (dsi_read(dsi, reg) & ~mask) | val);
+}
+
+static enum dsi_color dsi_color_from_mipi(enum mipi_dsi_pixel_format fmt)
+{
+	switch (fmt) {
+	case MIPI_DSI_FMT_RGB888:
+		return DSI_RGB888;
+	case MIPI_DSI_FMT_RGB666:
+		return DSI_RGB666_CONF2;
+	case MIPI_DSI_FMT_RGB666_PACKED:
+		return DSI_RGB666_CONF1;
+	case MIPI_DSI_FMT_RGB565:
+		return DSI_RGB565_CONF1;
+	default:
+		DRM_DEBUG_DRIVER("MIPI color invalid, so we use rgb888\n");
+	}
+	return DSI_RGB888;
+}
+
+static int dsi_pll_get_clkout_khz(int clkin_khz, int idf, int ndiv, int odf)
+{
+	int divisor = idf * odf;
+
+	/* prevent from division by 0 */
+	if (!divisor)
+		return 0;
+
+	return DIV_ROUND_CLOSEST(clkin_khz * ndiv, divisor);
+}
+
+static int dsi_pll_get_params(struct dw_mipi_dsi_stm *dsi,
+			      int clkin_khz, int clkout_khz,
+			      int *idf, int *ndiv, int *odf)
+{
+	int i, o, n, n_min, n_max;
+	int fvco_min, fvco_max, delta, best_delta; /* all in khz */
+
+	/* Early checks preventing division by 0 & odd results */
+	if (clkin_khz <= 0 || clkout_khz <= 0)
+		return -EINVAL;
+
+	fvco_min = dsi->lane_min_kbps * 2 * ODF_MAX;
+	fvco_max = dsi->lane_max_kbps * 2 * ODF_MIN;
+
+	best_delta = 1000000; /* big started value (1000000khz) */
+
+	for (i = IDF_MIN; i <= IDF_MAX; i++) {
+		/* Compute ndiv range according to Fvco */
+		n_min = ((fvco_min * i) / (2 * clkin_khz)) + 1;
+		n_max = (fvco_max * i) / (2 * clkin_khz);
+
+		/* No need to continue idf loop if we reach ndiv max */
+		if (n_min >= NDIV_MAX)
+			break;
+
+		/* Clamp ndiv to valid values */
+		if (n_min < NDIV_MIN)
+			n_min = NDIV_MIN;
+		if (n_max > NDIV_MAX)
+			n_max = NDIV_MAX;
+
+		for (o = ODF_MIN; o <= ODF_MAX; o *= 2) {
+			n = DIV_ROUND_CLOSEST(i * o * clkout_khz, clkin_khz);
+			/* Check ndiv according to vco range */
+			if (n < n_min || n > n_max)
+				continue;
+			/* Check if new delta is better & saves parameters */
+			delta = dsi_pll_get_clkout_khz(clkin_khz, i, n, o) -
+				clkout_khz;
+			if (delta < 0)
+				delta = -delta;
+			if (delta < best_delta) {
+				*idf = i;
+				*ndiv = n;
+				*odf = o;
+				best_delta = delta;
+			}
+			/* fast return in case of "perfect result" */
+			if (!delta)
+				return 0;
+		}
+	}
+
+	return 0;
+}
+
+#define clk_to_dw_mipi_dsi_stm(clk) \
+	container_of(clk, struct dw_mipi_dsi_stm, txbyte_clk)
+
+static void dw_mipi_dsi_clk_disable(struct clk_hw *clk)
+{
+	struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(clk);
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Disable the DSI PLL */
+	dsi_clear(dsi, DSI_WRPCR, WRPCR_PLLEN);
+
+	/* Disable the regulator */
+	dsi_clear(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
+}
+
+static int dw_mipi_dsi_clk_enable(struct clk_hw *clk)
+{
+	struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(clk);
+	u32 val;
+	int ret;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Enable the regulator */
+	dsi_set(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
+	ret = readl_poll_timeout_atomic(dsi->base + DSI_WISR, val, val & WISR_RRS,
+					SLEEP_US, TIMEOUT_US);
+	if (ret)
+		DRM_DEBUG_DRIVER("!TIMEOUT! waiting REGU, let's continue\n");
+
+	/* Enable the DSI PLL & wait for its lock */
+	dsi_set(dsi, DSI_WRPCR, WRPCR_PLLEN);
+	ret = readl_poll_timeout_atomic(dsi->base + DSI_WISR, val, val & WISR_PLLLS,
+					SLEEP_US, TIMEOUT_US);
+	if (ret)
+		DRM_DEBUG_DRIVER("!TIMEOUT! waiting PLL, let's continue\n");
+
+	return 0;
+}
+
+static int dw_mipi_dsi_clk_is_enabled(struct clk_hw *hw)
+{
+	struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+
+	return dsi_read(dsi, DSI_WRPCR) & WRPCR_PLLEN;
+}
+
+static unsigned long dw_mipi_dsi_clk_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+	unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+	u32 val;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	pll_in_khz = (unsigned int)(parent_rate / 1000);
+
+	val = dsi_read(dsi, DSI_WRPCR);
+
+	idf = (val & WRPCR_IDF) >> 11;
+	if (!idf)
+		idf = 1;
+	ndiv = (val & WRPCR_NDIV) >> 2;
+	odf = int_pow(2, (val & WRPCR_ODF) >> 16);
+
+	/* Get the adjusted pll out value */
+	pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+	return (unsigned long)pll_out_khz * 1000;
+}
+
+static int dw_mipi_dsi_clk_determine_rate(struct clk_hw *hw,
+					  struct clk_rate_request *req)
+{
+	struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+	unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+	int ret;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	pll_in_khz = (unsigned int)(req->best_parent_rate / 1000);
+
+	/* Compute best pll parameters */
+	idf = 0;
+	ndiv = 0;
+	odf = 0;
+
+	ret = dsi_pll_get_params(dsi, pll_in_khz, req->rate / 1000,
+				 &idf, &ndiv, &odf);
+	if (ret)
+		DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+
+	/* Get the adjusted pll out value */
+	pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+	req->rate = pll_out_khz * 1000;
+
+	return 0;
+}
+
+static int dw_mipi_dsi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+	unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+	int ret;
+	u32 val;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	pll_in_khz = (unsigned int)(parent_rate / 1000);
+
+	/* Compute best pll parameters */
+	idf = 0;
+	ndiv = 0;
+	odf = 0;
+
+	ret = dsi_pll_get_params(dsi, pll_in_khz, rate / 1000, &idf, &ndiv, &odf);
+	if (ret)
+		DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+
+	/* Get the adjusted pll out value */
+	pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+	/* Set the PLL division factors */
+	dsi_update_bits(dsi, DSI_WRPCR,	WRPCR_NDIV | WRPCR_IDF | WRPCR_ODF,
+			(ndiv << 2) | (idf << 11) | ((ffs(odf) - 1) << 16));
+
+	/* Compute uix4 & set the bit period in high-speed mode */
+	val = 4000000 / pll_out_khz;
+	dsi_update_bits(dsi, DSI_WPCR0, WPCR0_UIX4, val);
+
+	return 0;
+}
+
+static void dw_mipi_dsi_clk_unregister(void *data)
+{
+	struct dw_mipi_dsi_stm *dsi = data;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	of_clk_del_provider(dsi->dev->of_node);
+	clk_hw_unregister(&dsi->txbyte_clk);
+}
+
+static const struct clk_ops dw_mipi_dsi_stm_clk_ops = {
+	.enable = dw_mipi_dsi_clk_enable,
+	.disable = dw_mipi_dsi_clk_disable,
+	.is_enabled = dw_mipi_dsi_clk_is_enabled,
+	.recalc_rate = dw_mipi_dsi_clk_recalc_rate,
+	.determine_rate = dw_mipi_dsi_clk_determine_rate,
+	.set_rate = dw_mipi_dsi_clk_set_rate,
+};
+
+static struct clk_init_data cdata_init = {
+	.name = "ck_dsi_phy",
+	.ops = &dw_mipi_dsi_stm_clk_ops,
+	.parent_names = (const char * []) {"ck_hse"},
+	.num_parents = 1,
+};
+
+static int dw_mipi_dsi_clk_register(struct dw_mipi_dsi_stm *dsi,
+				    struct device *dev)
+{
+	struct device_node *node = dev->of_node;
+	int ret;
+
+	DRM_DEBUG_DRIVER("Registering clk\n");
+
+	dsi->txbyte_clk.init = &cdata_init;
+
+	ret = clk_hw_register(dev, &dsi->txbyte_clk);
+	if (ret)
+		return ret;
+
+	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get,
+				     &dsi->txbyte_clk);
+	if (ret)
+		clk_hw_unregister(&dsi->txbyte_clk);
+
+	return ret;
+}
+
+static int dw_mipi_dsi_phy_init(void *priv_data)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+	int ret;
+
+	ret = clk_prepare_enable(dsi->txbyte_clk.clk);
+	return ret;
+}
+
+static void dw_mipi_dsi_phy_power_on(void *priv_data)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Enable the DSI wrapper */
+	dsi_set(dsi, DSI_WCR, WCR_DSIEN);
+}
+
+static void dw_mipi_dsi_phy_power_off(void *priv_data)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	clk_disable_unprepare(dsi->txbyte_clk.clk);
+
+	/* Disable the DSI wrapper */
+	dsi_clear(dsi, DSI_WCR, WCR_DSIEN);
+}
+
+static int
+dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
+			  unsigned long mode_flags, u32 lanes, u32 format,
+			  unsigned int *lane_mbps)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+	unsigned int pll_in_khz, pll_out_khz;
+	int ret, bpp;
+
+	pll_in_khz = (unsigned int)(clk_get_rate(dsi->pllref_clk) / 1000);
+
+	/* Compute requested pll out */
+	bpp = mipi_dsi_pixel_format_to_bpp(format);
+	pll_out_khz = mode->clock * bpp / lanes;
+
+	/* Add 20% to pll out to be higher than pixel bw (burst mode only) */
+	if (mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
+		pll_out_khz = (pll_out_khz * 12) / 10;
+
+	if (pll_out_khz > dsi->lane_max_kbps) {
+		pll_out_khz = dsi->lane_max_kbps;
+		DRM_WARN("Warning max phy mbps is used\n");
+	}
+	if (pll_out_khz < dsi->lane_min_kbps) {
+		pll_out_khz = dsi->lane_min_kbps;
+		DRM_WARN("Warning min phy mbps is used\n");
+	}
+
+	ret = clk_set_rate((dsi->txbyte_clk.clk), pll_out_khz * 1000);
+	if (ret)
+		DRM_DEBUG_DRIVER("ERROR Could not set rate of %d to %s clk->name",
+				 pll_out_khz, clk_hw_get_name(&dsi->txbyte_clk));
+
+	/* Select video mode by resetting DSIM bit */
+	dsi_clear(dsi, DSI_WCFGR, WCFGR_DSIM);
+
+	/* Select the color coding */
+	dsi_update_bits(dsi, DSI_WCFGR, WCFGR_COLMUX,
+			dsi_color_from_mipi(format) << 1);
+
+	*lane_mbps = pll_out_khz / 1000;
+
+	DRM_DEBUG_DRIVER("pll_in %ukHz pll_out %ukHz lane_mbps %uMHz\n",
+			 pll_in_khz, pll_out_khz, *lane_mbps);
+
+	return 0;
+}
+
+#define DSI_PHY_DELAY(fp, vp, mbps) DIV_ROUND_UP((fp) * (mbps) + 1000 * (vp), 8000)
+
+static int
+dw_mipi_dsi_phy_get_timing(void *priv_data, unsigned int lane_mbps,
+			   struct dw_mipi_dsi_dphy_timing *timing)
+{
+	/*
+	 * From STM32MP157 datasheet, valid for STM32F469, STM32F7x9, STM32H747
+	 * phy_clkhs2lp_time = (272+136*UI)/(8*UI)
+	 * phy_clklp2hs_time = (512+40*UI)/(8*UI)
+	 * phy_hs2lp_time = (192+64*UI)/(8*UI)
+	 * phy_lp2hs_time = (256+32*UI)/(8*UI)
+	 */
+	timing->clk_hs2lp = DSI_PHY_DELAY(272, 136, lane_mbps);
+	timing->clk_lp2hs = DSI_PHY_DELAY(512, 40, lane_mbps);
+	timing->data_hs2lp = DSI_PHY_DELAY(192, 64, lane_mbps);
+	timing->data_lp2hs = DSI_PHY_DELAY(256, 32, lane_mbps);
+
+	return 0;
+}
+
+#define CLK_TOLERANCE_HZ 50
+
+static enum drm_mode_status
+dw_mipi_dsi_stm_mode_valid(void *priv_data,
+			   const struct drm_display_mode *mode,
+			   unsigned long mode_flags, u32 lanes, u32 format)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+	unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+	int ret, bpp;
+
+	bpp = mipi_dsi_pixel_format_to_bpp(format);
+	if (bpp < 0)
+		return MODE_BAD;
+
+	/* Compute requested pll out */
+	pll_out_khz = mode->clock * bpp / lanes;
+
+	if (pll_out_khz > dsi->lane_max_kbps)
+		return MODE_CLOCK_HIGH;
+
+	if (mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
+		/* Add 20% to pll out to be higher than pixel bw */
+		pll_out_khz = (pll_out_khz * 12) / 10;
+	} else {
+		if (pll_out_khz < dsi->lane_min_kbps)
+			return MODE_CLOCK_LOW;
+	}
+
+	/* Compute best pll parameters */
+	idf = 0;
+	ndiv = 0;
+	odf = 0;
+	pll_in_khz = clk_get_rate(dsi->pllref_clk) / 1000;
+	ret = dsi_pll_get_params(dsi, pll_in_khz, pll_out_khz, &idf, &ndiv, &odf);
+	if (ret) {
+		DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+		return MODE_ERROR;
+	}
+
+	if (!(mode_flags & MIPI_DSI_MODE_VIDEO_BURST)) {
+		unsigned int px_clock_hz, target_px_clock_hz, lane_mbps;
+		int dsi_short_packet_size_px, hfp, hsync, hbp, delay_to_lp;
+		struct dw_mipi_dsi_dphy_timing dphy_timing;
+
+		/* Get the adjusted pll out value */
+		pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+		px_clock_hz = DIV_ROUND_CLOSEST_ULL(1000ULL * pll_out_khz * lanes, bpp);
+		target_px_clock_hz = mode->clock * 1000;
+		/*
+		 * Filter modes according to the clock value, particularly useful for
+		 * hdmi modes that require precise pixel clocks.
+		 */
+		if (px_clock_hz < target_px_clock_hz - CLK_TOLERANCE_HZ ||
+		    px_clock_hz > target_px_clock_hz + CLK_TOLERANCE_HZ)
+			return MODE_CLOCK_RANGE;
+
+		/* sync packets are codes as DSI short packets (4 bytes) */
+		dsi_short_packet_size_px = DIV_ROUND_UP(4 * BITS_PER_BYTE, bpp);
+
+		hfp = mode->hsync_start - mode->hdisplay;
+		hsync = mode->hsync_end - mode->hsync_start;
+		hbp = mode->htotal - mode->hsync_end;
+
+		/* hsync must be longer than 4 bytes HSS packets */
+		if (hsync < dsi_short_packet_size_px)
+			return MODE_HSYNC_NARROW;
+
+		if (mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
+			/* HBP must be longer than 4 bytes HSE packets */
+			if (hbp < dsi_short_packet_size_px)
+				return MODE_HSYNC_NARROW;
+			hbp -= dsi_short_packet_size_px;
+		} else {
+			/* With sync events HBP extends in the hsync */
+			hbp += hsync - dsi_short_packet_size_px;
+		}
+
+		lane_mbps = pll_out_khz / 1000;
+		ret = dw_mipi_dsi_phy_get_timing(priv_data, lane_mbps, &dphy_timing);
+		if (ret)
+			return MODE_ERROR;
+		/*
+		 * In non-burst mode DSI has to enter in LP during HFP
+		 * (horizontal front porch) or HBP (horizontal back porch) to
+		 * resync with LTDC pixel clock.
+		 */
+		delay_to_lp = DIV_ROUND_UP((dphy_timing.data_hs2lp + dphy_timing.data_lp2hs) *
+					   lanes * BITS_PER_BYTE, bpp);
+		if (hfp < delay_to_lp && hbp < delay_to_lp)
+			return MODE_HSYNC;
+	}
+
+	return MODE_OK;
+}
+
+static const struct dw_mipi_dsi_phy_ops dw_mipi_dsi_stm_phy_ops = {
+	.init = dw_mipi_dsi_phy_init,
+	.power_on = dw_mipi_dsi_phy_power_on,
+	.power_off = dw_mipi_dsi_phy_power_off,
+	.get_lane_mbps = dw_mipi_dsi_get_lane_mbps,
+	.get_timing = dw_mipi_dsi_phy_get_timing,
+};
+
+static struct dw_mipi_dsi_plat_data dw_mipi_dsi_stm_plat_data = {
+	.max_data_lanes = 2,
+	.mode_valid = dw_mipi_dsi_stm_mode_valid,
+	.phy_ops = &dw_mipi_dsi_stm_phy_ops,
+};
+
+static const struct of_device_id dw_mipi_dsi_stm_dt_ids[] = {
+	{ .compatible = "st,stm32-dsi", .data = &dw_mipi_dsi_stm_plat_data, },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, dw_mipi_dsi_stm_dt_ids);
+
+static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dw_mipi_dsi_stm *dsi;
+	const struct dw_mipi_dsi_plat_data *pdata = of_device_get_match_data(dev);
+	int ret;
+
+	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
+	if (!dsi)
+		return -ENOMEM;
+
+	dsi->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(dsi->base)) {
+		ret = PTR_ERR(dsi->base);
+		DRM_ERROR("Unable to get dsi registers %d\n", ret);
+		return ret;
+	}
+
+	dsi->vdd_supply = devm_regulator_get(dev, "phy-dsi");
+	if (IS_ERR(dsi->vdd_supply)) {
+		ret = PTR_ERR(dsi->vdd_supply);
+		dev_err_probe(dev, ret, "Failed to request regulator\n");
+		return ret;
+	}
+
+	ret = regulator_enable(dsi->vdd_supply);
+	if (ret) {
+		DRM_ERROR("Failed to enable regulator: %d\n", ret);
+		return ret;
+	}
+
+	dsi->pllref_clk = devm_clk_get(dev, "ref");
+	if (IS_ERR(dsi->pllref_clk)) {
+		ret = PTR_ERR(dsi->pllref_clk);
+		dev_err_probe(dev, ret, "Unable to get pll reference clock\n");
+		goto err_clk_get;
+	}
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		DRM_ERROR("Failed to enable pllref_clk: %d\n", ret);
+		goto err_clk_get;
+	}
+
+	dsi->pclk = devm_clk_get(dev, "pclk");
+	if (IS_ERR(dsi->pclk)) {
+		ret = PTR_ERR(dsi->pclk);
+		DRM_ERROR("Unable to get peripheral clock: %d\n", ret);
+		goto err_dsi_probe;
+	}
+
+	ret = clk_prepare_enable(dsi->pclk);
+	if (ret) {
+		DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__);
+		goto err_dsi_probe;
+	}
+
+	dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
+	clk_disable_unprepare(dsi->pclk);
+
+	if (dsi->hw_version != HWVER_130 && dsi->hw_version != HWVER_131) {
+		ret = -ENODEV;
+		DRM_ERROR("bad dsi hardware version\n");
+		goto err_dsi_probe;
+	}
+
+	/* set lane capabilities according to hw version */
+	dsi->lane_min_kbps = LANE_MIN_KBPS;
+	dsi->lane_max_kbps = LANE_MAX_KBPS;
+	if (dsi->hw_version == HWVER_131) {
+		dsi->lane_min_kbps *= 2;
+		dsi->lane_max_kbps *= 2;
+	}
+
+	dsi->pdata = *pdata;
+	dsi->pdata.base = dsi->base;
+	dsi->pdata.priv_data = dsi;
+
+	dsi->pdata.max_data_lanes = 2;
+	dsi->pdata.phy_ops = &dw_mipi_dsi_stm_phy_ops;
+
+	platform_set_drvdata(pdev, dsi);
+
+	dsi->dsi = dw_mipi_dsi_probe(pdev, &dsi->pdata);
+	if (IS_ERR(dsi->dsi)) {
+		ret = PTR_ERR(dsi->dsi);
+		dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
+		goto err_dsi_probe;
+	}
+
+	/*
+	 * We need to wait for the generic bridge to probe before enabling and
+	 * register the internal pixel clock.
+	 */
+	ret = clk_prepare_enable(dsi->pclk);
+	if (ret) {
+		DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__);
+		goto err_dsi_probe;
+	}
+
+	ret = dw_mipi_dsi_clk_register(dsi, dev);
+	if (ret) {
+		DRM_ERROR("Failed to register DSI pixel clock: %d\n", ret);
+		clk_disable_unprepare(dsi->pclk);
+		goto err_dsi_probe;
+	}
+
+	clk_disable_unprepare(dsi->pclk);
+
+	return 0;
+
+err_dsi_probe:
+	clk_disable_unprepare(dsi->pllref_clk);
+err_clk_get:
+	regulator_disable(dsi->vdd_supply);
+
+	return ret;
+}
+
+static void dw_mipi_dsi_stm_remove(struct platform_device *pdev)
+{
+	struct dw_mipi_dsi_stm *dsi = platform_get_drvdata(pdev);
+
+	dw_mipi_dsi_remove(dsi->dsi);
+	clk_disable_unprepare(dsi->pllref_clk);
+	dw_mipi_dsi_clk_unregister(dsi);
+	regulator_disable(dsi->vdd_supply);
+}
+
+static int dw_mipi_dsi_stm_suspend(struct device *dev)
+{
+	struct dw_mipi_dsi_stm *dsi = dev_get_drvdata(dev);
+
+	DRM_DEBUG_DRIVER("\n");
+
+	clk_disable_unprepare(dsi->pllref_clk);
+	clk_disable_unprepare(dsi->pclk);
+	regulator_disable(dsi->vdd_supply);
+
+	return 0;
+}
+
+static int dw_mipi_dsi_stm_resume(struct device *dev)
+{
+	struct dw_mipi_dsi_stm *dsi = dev_get_drvdata(dev);
+	int ret;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	ret = regulator_enable(dsi->vdd_supply);
+	if (ret) {
+		DRM_ERROR("Failed to enable regulator: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(dsi->pclk);
+	if (ret) {
+		regulator_disable(dsi->vdd_supply);
+		DRM_ERROR("Failed to enable pclk: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		clk_disable_unprepare(dsi->pclk);
+		regulator_disable(dsi->vdd_supply);
+		DRM_ERROR("Failed to enable pllref_clk: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops dw_mipi_dsi_stm_pm_ops = {
+	SYSTEM_SLEEP_PM_OPS(dw_mipi_dsi_stm_suspend,
+			    dw_mipi_dsi_stm_resume)
+	RUNTIME_PM_OPS(dw_mipi_dsi_stm_suspend,
+		       dw_mipi_dsi_stm_resume, NULL)
+};
+
+static struct platform_driver dw_mipi_dsi_stm_driver = {
+	.probe		= dw_mipi_dsi_stm_probe,
+	.remove		= dw_mipi_dsi_stm_remove,
+	.driver		= {
+		.of_match_table = dw_mipi_dsi_stm_dt_ids,
+		.name	= "stm32-display-dsi",
+		.pm = &dw_mipi_dsi_stm_pm_ops,
+	},
+};
+
+module_platform_driver(dw_mipi_dsi_stm_driver);
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics DW MIPI DSI host controller driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
new file mode 100644
index 000000000..8818dcf98
--- /dev/null
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -0,0 +1,2116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Mickael Reulier <mickael.reulier@st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_blend.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_device.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_fb_dma_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <drm/drm_vblank.h>
+#include <drm/drm_managed.h>
+
+#include <video/videomode.h>
+
+#include "ltdc.h"
+
+#define NB_CRTC 1
+#define CRTC_MASK GENMASK(NB_CRTC - 1, 0)
+
+#define MAX_IRQ 4
+
+#define HWVER_10200 0x010200
+#define HWVER_10300 0x010300
+#define HWVER_20101 0x020101
+#define HWVER_40100 0x040100
+#define HWVER_40101 0x040101
+
+/*
+ * The address of some registers depends on the HW version: such registers have
+ * an extra offset specified with layer_ofs.
+ */
+#define LAY_OFS_0	0x80
+#define LAY_OFS_1	0x100
+#define LAY_OFS	(ldev->caps.layer_ofs)
+
+/* Global register offsets */
+#define LTDC_IDR	0x0000		/* IDentification */
+#define LTDC_LCR	0x0004		/* Layer Count */
+#define LTDC_SSCR	0x0008		/* Synchronization Size Configuration */
+#define LTDC_BPCR	0x000C		/* Back Porch Configuration */
+#define LTDC_AWCR	0x0010		/* Active Width Configuration */
+#define LTDC_TWCR	0x0014		/* Total Width Configuration */
+#define LTDC_GCR	0x0018		/* Global Control */
+#define LTDC_GC1R	0x001C		/* Global Configuration 1 */
+#define LTDC_GC2R	0x0020		/* Global Configuration 2 */
+#define LTDC_SRCR	0x0024		/* Shadow Reload Configuration */
+#define LTDC_GACR	0x0028		/* GAmma Correction */
+#define LTDC_BCCR	0x002C		/* Background Color Configuration */
+#define LTDC_IER	0x0034		/* Interrupt Enable */
+#define LTDC_ISR	0x0038		/* Interrupt Status */
+#define LTDC_ICR	0x003C		/* Interrupt Clear */
+#define LTDC_LIPCR	0x0040		/* Line Interrupt Position Conf. */
+#define LTDC_CPSR	0x0044		/* Current Position Status */
+#define LTDC_CDSR	0x0048		/* Current Display Status */
+#define LTDC_EDCR	0x0060		/* External Display Control */
+#define LTDC_CCRCR	0x007C		/* Computed CRC value */
+#define LTDC_FUT	0x0090		/* Fifo underrun Threshold */
+
+/* Layer register offsets */
+#define LTDC_L1C0R	(ldev->caps.layer_regs[0])	/* L1 configuration 0 */
+#define LTDC_L1C1R	(ldev->caps.layer_regs[1])	/* L1 configuration 1 */
+#define LTDC_L1RCR	(ldev->caps.layer_regs[2])	/* L1 reload control */
+#define LTDC_L1CR	(ldev->caps.layer_regs[3])	/* L1 control register */
+#define LTDC_L1WHPCR	(ldev->caps.layer_regs[4])	/* L1 window horizontal position configuration */
+#define LTDC_L1WVPCR	(ldev->caps.layer_regs[5])	/* L1 window vertical position configuration */
+#define LTDC_L1CKCR	(ldev->caps.layer_regs[6])	/* L1 color keying configuration */
+#define LTDC_L1PFCR	(ldev->caps.layer_regs[7])	/* L1 pixel format configuration */
+#define LTDC_L1CACR	(ldev->caps.layer_regs[8])	/* L1 constant alpha configuration */
+#define LTDC_L1DCCR	(ldev->caps.layer_regs[9])	/* L1 default color configuration */
+#define LTDC_L1BFCR	(ldev->caps.layer_regs[10])	/* L1 blending factors configuration */
+#define LTDC_L1BLCR	(ldev->caps.layer_regs[11])	/* L1 burst length configuration */
+#define LTDC_L1PCR	(ldev->caps.layer_regs[12])	/* L1 planar configuration */
+#define LTDC_L1CFBAR	(ldev->caps.layer_regs[13])	/* L1 color frame buffer address */
+#define LTDC_L1CFBLR	(ldev->caps.layer_regs[14])	/* L1 color frame buffer length */
+#define LTDC_L1CFBLNR	(ldev->caps.layer_regs[15])	/* L1 color frame buffer line number */
+#define LTDC_L1AFBA0R	(ldev->caps.layer_regs[16])	/* L1 auxiliary frame buffer address 0 */
+#define LTDC_L1AFBA1R	(ldev->caps.layer_regs[17])	/* L1 auxiliary frame buffer address 1 */
+#define LTDC_L1AFBLR	(ldev->caps.layer_regs[18])	/* L1 auxiliary frame buffer length */
+#define LTDC_L1AFBLNR	(ldev->caps.layer_regs[19])	/* L1 auxiliary frame buffer line number */
+#define LTDC_L1CLUTWR	(ldev->caps.layer_regs[20])	/* L1 CLUT write */
+#define LTDC_L1CYR0R	(ldev->caps.layer_regs[21])	/* L1 Conversion YCbCr RGB 0 */
+#define LTDC_L1CYR1R	(ldev->caps.layer_regs[22])	/* L1 Conversion YCbCr RGB 1 */
+#define LTDC_L1FPF0R	(ldev->caps.layer_regs[23])	/* L1 Flexible Pixel Format 0 */
+#define LTDC_L1FPF1R	(ldev->caps.layer_regs[24])	/* L1 Flexible Pixel Format 1 */
+
+/* Bit definitions */
+#define SSCR_VSH	GENMASK(10, 0)	/* Vertical Synchronization Height */
+#define SSCR_HSW	GENMASK(27, 16)	/* Horizontal Synchronization Width */
+
+#define BPCR_AVBP	GENMASK(10, 0)	/* Accumulated Vertical Back Porch */
+#define BPCR_AHBP	GENMASK(27, 16)	/* Accumulated Horizontal Back Porch */
+
+#define AWCR_AAH	GENMASK(10, 0)	/* Accumulated Active Height */
+#define AWCR_AAW	GENMASK(27, 16)	/* Accumulated Active Width */
+
+#define TWCR_TOTALH	GENMASK(10, 0)	/* TOTAL Height */
+#define TWCR_TOTALW	GENMASK(27, 16)	/* TOTAL Width */
+
+#define GCR_LTDCEN	BIT(0)		/* LTDC ENable */
+#define GCR_DEN		BIT(16)		/* Dither ENable */
+#define GCR_CRCEN	BIT(19)		/* CRC ENable */
+#define GCR_PCPOL	BIT(28)		/* Pixel Clock POLarity-Inverted */
+#define GCR_DEPOL	BIT(29)		/* Data Enable POLarity-High */
+#define GCR_VSPOL	BIT(30)		/* Vertical Synchro POLarity-High */
+#define GCR_HSPOL	BIT(31)		/* Horizontal Synchro POLarity-High */
+
+#define GC1R_WBCH	GENMASK(3, 0)	/* Width of Blue CHannel output */
+#define GC1R_WGCH	GENMASK(7, 4)	/* Width of Green Channel output */
+#define GC1R_WRCH	GENMASK(11, 8)	/* Width of Red Channel output */
+#define GC1R_PBEN	BIT(12)		/* Precise Blending ENable */
+#define GC1R_DT		GENMASK(15, 14)	/* Dithering Technique */
+#define GC1R_GCT	GENMASK(19, 17)	/* Gamma Correction Technique */
+#define GC1R_SHREN	BIT(21)		/* SHadow Registers ENabled */
+#define GC1R_BCP	BIT(22)		/* Background Colour Programmable */
+#define GC1R_BBEN	BIT(23)		/* Background Blending ENabled */
+#define GC1R_LNIP	BIT(24)		/* Line Number IRQ Position */
+#define GC1R_TP		BIT(25)		/* Timing Programmable */
+#define GC1R_IPP	BIT(26)		/* IRQ Polarity Programmable */
+#define GC1R_SPP	BIT(27)		/* Sync Polarity Programmable */
+#define GC1R_DWP	BIT(28)		/* Dither Width Programmable */
+#define GC1R_STREN	BIT(29)		/* STatus Registers ENabled */
+#define GC1R_BMEN	BIT(31)		/* Blind Mode ENabled */
+
+#define GC2R_EDCA	BIT(0)		/* External Display Control Ability  */
+#define GC2R_STSAEN	BIT(1)		/* Slave Timing Sync Ability ENabled */
+#define GC2R_DVAEN	BIT(2)		/* Dual-View Ability ENabled */
+#define GC2R_DPAEN	BIT(3)		/* Dual-Port Ability ENabled */
+#define GC2R_BW		GENMASK(6, 4)	/* Bus Width (log2 of nb of bytes) */
+#define GC2R_EDCEN	BIT(7)		/* External Display Control ENabled */
+
+#define SRCR_IMR	BIT(0)		/* IMmediate Reload */
+#define SRCR_VBR	BIT(1)		/* Vertical Blanking Reload */
+
+#define BCCR_BCBLACK	0x00		/* Background Color BLACK */
+#define BCCR_BCBLUE	GENMASK(7, 0)	/* Background Color BLUE */
+#define BCCR_BCGREEN	GENMASK(15, 8)	/* Background Color GREEN */
+#define BCCR_BCRED	GENMASK(23, 16)	/* Background Color RED */
+#define BCCR_BCWHITE	GENMASK(23, 0)	/* Background Color WHITE */
+
+#define IER_LIE		BIT(0)		/* Line Interrupt Enable */
+#define IER_FUWIE	BIT(1)		/* Fifo Underrun Warning Interrupt Enable */
+#define IER_TERRIE	BIT(2)		/* Transfer ERRor Interrupt Enable */
+#define IER_RRIE	BIT(3)		/* Register Reload Interrupt Enable */
+#define IER_FUEIE	BIT(6)		/* Fifo Underrun Error Interrupt Enable */
+#define IER_CRCIE	BIT(7)		/* CRC Error Interrupt Enable */
+#define IER_MASK (IER_LIE | IER_FUWIE | IER_TERRIE | IER_RRIE | IER_FUEIE | IER_CRCIE)
+
+#define CPSR_CYPOS	GENMASK(15, 0)	/* Current Y position */
+
+#define ISR_LIF		BIT(0)		/* Line Interrupt Flag */
+#define ISR_FUWIF	BIT(1)		/* Fifo Underrun Warning Interrupt Flag */
+#define ISR_TERRIF	BIT(2)		/* Transfer ERRor Interrupt Flag */
+#define ISR_RRIF	BIT(3)		/* Register Reload Interrupt Flag */
+#define ISR_FUEIF	BIT(6)		/* Fifo Underrun Error Interrupt Flag */
+#define ISR_CRCIF	BIT(7)		/* CRC Error Interrupt Flag */
+
+#define EDCR_OCYEN	BIT(25)		/* Output Conversion to YCbCr 422: ENable */
+#define EDCR_OCYSEL	BIT(26)		/* Output Conversion to YCbCr 422: SELection of the CCIR */
+#define EDCR_OCYCO	BIT(27)		/* Output Conversion to YCbCr 422: Chrominance Order */
+
+#define LXCR_LEN	BIT(0)		/* Layer ENable */
+#define LXCR_COLKEN	BIT(1)		/* Color Keying Enable */
+#define LXCR_CLUTEN	BIT(4)		/* Color Look-Up Table ENable */
+#define LXCR_HMEN	BIT(8)		/* Horizontal Mirroring ENable */
+#define LXCR_MASK (LXCR_LEN | LXCR_COLKEN | LXCR_CLUTEN | LXCR_HMEN)
+
+#define LXWHPCR_WHSTPOS	GENMASK(11, 0)	/* Window Horizontal StarT POSition */
+#define LXWHPCR_WHSPPOS	GENMASK(27, 16)	/* Window Horizontal StoP POSition */
+
+#define LXWVPCR_WVSTPOS	GENMASK(10, 0)	/* Window Vertical StarT POSition */
+#define LXWVPCR_WVSPPOS	GENMASK(26, 16)	/* Window Vertical StoP POSition */
+
+#define LXPFCR_PF	GENMASK(2, 0)	/* Pixel Format */
+#define PF_FLEXIBLE	0x7		/* Flexible Pixel Format selected */
+
+#define LXCACR_CONSTA	GENMASK(7, 0)	/* CONSTant Alpha */
+
+#define LXBFCR_BF2	GENMASK(2, 0)	/* Blending Factor 2 */
+#define LXBFCR_BF1	GENMASK(10, 8)	/* Blending Factor 1 */
+#define LXBFCR_BOR	GENMASK(18, 16) /* Blending ORder */
+
+#define LXCFBLR_CFBLL	GENMASK(12, 0)	/* Color Frame Buffer Line Length */
+#define LXCFBLR_CFBP	GENMASK(31, 16) /* Color Frame Buffer Pitch in bytes */
+
+#define LXCFBLNR_CFBLN	GENMASK(10, 0)	/* Color Frame Buffer Line Number */
+
+#define LXCR_C1R_YIA	BIT(0)		/* Ycbcr 422 Interleaved Ability */
+#define LXCR_C1R_YSPA	BIT(1)		/* Ycbcr 420 Semi-Planar Ability */
+#define LXCR_C1R_YFPA	BIT(2)		/* Ycbcr 420 Full-Planar Ability */
+#define LXCR_C1R_SCA	BIT(31)		/* SCaling Ability*/
+
+#define LxPCR_YREN	BIT(9)		/* Y Rescale Enable for the color dynamic range */
+#define LxPCR_OF	BIT(8)		/* Odd pixel First */
+#define LxPCR_CBF	BIT(7)		/* CB component First */
+#define LxPCR_YF	BIT(6)		/* Y component First */
+#define LxPCR_YCM	GENMASK(5, 4)	/* Ycbcr Conversion Mode */
+#define YCM_I		0x0		/* Interleaved 422 */
+#define YCM_SP		0x1		/* Semi-Planar 420 */
+#define YCM_FP		0x2		/* Full-Planar 420 */
+#define LxPCR_YCEN	BIT(3)		/* YCbCr-to-RGB Conversion Enable */
+
+#define LXRCR_IMR	BIT(0)		/* IMmediate Reload */
+#define LXRCR_VBR	BIT(1)		/* Vertical Blanking Reload */
+#define LXRCR_GRMSK	BIT(2)		/* Global (centralized) Reload MaSKed */
+
+#define CLUT_SIZE	256
+
+#define CONSTA_MAX	0xFF		/* CONSTant Alpha MAX= 1.0 */
+#define BF1_PAXCA	0x600		/* Pixel Alpha x Constant Alpha */
+#define BF1_CA		0x400		/* Constant Alpha */
+#define BF2_1PAXCA	0x007		/* 1 - (Pixel Alpha x Constant Alpha) */
+#define BF2_1CA		0x005		/* 1 - Constant Alpha */
+
+#define NB_PF		8		/* Max nb of HW pixel format */
+
+#define FUT_DFT		128		/* Default value of fifo underrun threshold */
+
+/*
+ * Skip the first value and the second in case CRC was enabled during
+ * the thread irq. This is to be sure CRC value is relevant for the
+ * frame.
+ */
+#define CRC_SKIP_FRAMES 2
+
+enum ltdc_pix_fmt {
+	PF_NONE,
+	/* RGB formats */
+	PF_ARGB8888,		/* ARGB [32 bits] */
+	PF_RGBA8888,		/* RGBA [32 bits] */
+	PF_ABGR8888,		/* ABGR [32 bits] */
+	PF_BGRA8888,		/* BGRA [32 bits] */
+	PF_RGB888,		/* RGB [24 bits] */
+	PF_BGR888,		/* BGR [24 bits] */
+	PF_RGB565,		/* RGB [16 bits] */
+	PF_BGR565,		/* BGR [16 bits] */
+	PF_ARGB1555,		/* ARGB A:1 bit RGB:15 bits [16 bits] */
+	PF_ARGB4444,		/* ARGB A:4 bits R/G/B: 4 bits each [16 bits] */
+	/* Indexed formats */
+	PF_L8,			/* Indexed 8 bits [8 bits] */
+	PF_AL44,		/* Alpha:4 bits + indexed 4 bits [8 bits] */
+	PF_AL88			/* Alpha:8 bits + indexed 8 bits [16 bits] */
+};
+
+/* The index gives the encoding of the pixel format for an HW version */
+static const enum ltdc_pix_fmt ltdc_pix_fmt_a0[NB_PF] = {
+	PF_ARGB8888,		/* 0x00 */
+	PF_RGB888,		/* 0x01 */
+	PF_RGB565,		/* 0x02 */
+	PF_ARGB1555,		/* 0x03 */
+	PF_ARGB4444,		/* 0x04 */
+	PF_L8,			/* 0x05 */
+	PF_AL44,		/* 0x06 */
+	PF_AL88			/* 0x07 */
+};
+
+static const enum ltdc_pix_fmt ltdc_pix_fmt_a1[NB_PF] = {
+	PF_ARGB8888,		/* 0x00 */
+	PF_RGB888,		/* 0x01 */
+	PF_RGB565,		/* 0x02 */
+	PF_RGBA8888,		/* 0x03 */
+	PF_AL44,		/* 0x04 */
+	PF_L8,			/* 0x05 */
+	PF_ARGB1555,		/* 0x06 */
+	PF_ARGB4444		/* 0x07 */
+};
+
+static const enum ltdc_pix_fmt ltdc_pix_fmt_a2[NB_PF] = {
+	PF_ARGB8888,		/* 0x00 */
+	PF_ABGR8888,		/* 0x01 */
+	PF_RGBA8888,		/* 0x02 */
+	PF_BGRA8888,		/* 0x03 */
+	PF_RGB565,		/* 0x04 */
+	PF_BGR565,		/* 0x05 */
+	PF_RGB888,		/* 0x06 */
+	PF_NONE			/* 0x07 */
+};
+
+static const u32 ltdc_drm_fmt_a0[] = {
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_RGB888,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_ARGB1555,
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_ARGB4444,
+	DRM_FORMAT_XRGB4444,
+	DRM_FORMAT_C8
+};
+
+static const u32 ltdc_drm_fmt_a1[] = {
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_RGB888,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_RGBA8888,
+	DRM_FORMAT_RGBX8888,
+	DRM_FORMAT_ARGB1555,
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_ARGB4444,
+	DRM_FORMAT_XRGB4444,
+	DRM_FORMAT_C8
+};
+
+static const u32 ltdc_drm_fmt_a2[] = {
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_ABGR8888,
+	DRM_FORMAT_XBGR8888,
+	DRM_FORMAT_RGBA8888,
+	DRM_FORMAT_RGBX8888,
+	DRM_FORMAT_BGRA8888,
+	DRM_FORMAT_BGRX8888,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_BGR565,
+	DRM_FORMAT_RGB888,
+	DRM_FORMAT_BGR888,
+	DRM_FORMAT_ARGB1555,
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_ARGB4444,
+	DRM_FORMAT_XRGB4444,
+	DRM_FORMAT_C8
+};
+
+static const u32 ltdc_drm_fmt_ycbcr_cp[] = {
+	DRM_FORMAT_YUYV,
+	DRM_FORMAT_YVYU,
+	DRM_FORMAT_UYVY,
+	DRM_FORMAT_VYUY
+};
+
+static const u32 ltdc_drm_fmt_ycbcr_sp[] = {
+	DRM_FORMAT_NV12,
+	DRM_FORMAT_NV21
+};
+
+static const u32 ltdc_drm_fmt_ycbcr_fp[] = {
+	DRM_FORMAT_YUV420,
+	DRM_FORMAT_YVU420
+};
+
+/* Layer register offsets */
+static const u32 ltdc_layer_regs_a0[] = {
+	0x80,	/* L1 configuration 0 */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x84,	/* L1 control register */
+	0x88,	/* L1 window horizontal position configuration */
+	0x8c,	/* L1 window vertical position configuration */
+	0x90,	/* L1 color keying configuration */
+	0x94,	/* L1 pixel format configuration */
+	0x98,	/* L1 constant alpha configuration */
+	0x9c,	/* L1 default color configuration */
+	0xa0,	/* L1 blending factors configuration */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0xac,	/* L1 color frame buffer address */
+	0xb0,	/* L1 color frame buffer length */
+	0xb4,	/* L1 color frame buffer line number */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0xc4,	/* L1 CLUT write */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x00	/* not available */
+};
+
+static const u32 ltdc_layer_regs_a1[] = {
+	0x80,	/* L1 configuration 0 */
+	0x84,	/* L1 configuration 1 */
+	0x00,	/* L1 reload control */
+	0x88,	/* L1 control register */
+	0x8c,	/* L1 window horizontal position configuration */
+	0x90,	/* L1 window vertical position configuration */
+	0x94,	/* L1 color keying configuration */
+	0x98,	/* L1 pixel format configuration */
+	0x9c,	/* L1 constant alpha configuration */
+	0xa0,	/* L1 default color configuration */
+	0xa4,	/* L1 blending factors configuration */
+	0xa8,	/* L1 burst length configuration */
+	0x00,	/* not available */
+	0xac,	/* L1 color frame buffer address */
+	0xb0,	/* L1 color frame buffer length */
+	0xb4,	/* L1 color frame buffer line number */
+	0xb8,	/* L1 auxiliary frame buffer address 0 */
+	0xbc,	/* L1 auxiliary frame buffer address 1 */
+	0xc0,	/* L1 auxiliary frame buffer length */
+	0xc4,	/* L1 auxiliary frame buffer line number */
+	0xc8,	/* L1 CLUT write */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x00,	/* not available */
+	0x00	/* not available */
+};
+
+static const u32 ltdc_layer_regs_a2[] = {
+	0x100,	/* L1 configuration 0 */
+	0x104,	/* L1 configuration 1 */
+	0x108,	/* L1 reload control */
+	0x10c,	/* L1 control register */
+	0x110,	/* L1 window horizontal position configuration */
+	0x114,	/* L1 window vertical position configuration */
+	0x118,	/* L1 color keying configuration */
+	0x11c,	/* L1 pixel format configuration */
+	0x120,	/* L1 constant alpha configuration */
+	0x124,	/* L1 default color configuration */
+	0x128,	/* L1 blending factors configuration */
+	0x12c,	/* L1 burst length configuration */
+	0x130,	/* L1 planar configuration */
+	0x134,	/* L1 color frame buffer address */
+	0x138,	/* L1 color frame buffer length */
+	0x13c,	/* L1 color frame buffer line number */
+	0x140,	/* L1 auxiliary frame buffer address 0 */
+	0x144,	/* L1 auxiliary frame buffer address 1 */
+	0x148,	/* L1 auxiliary frame buffer length */
+	0x14c,	/* L1 auxiliary frame buffer line number */
+	0x150,	/* L1 CLUT write */
+	0x16c,	/* L1 Conversion YCbCr RGB 0 */
+	0x170,	/* L1 Conversion YCbCr RGB 1 */
+	0x174,	/* L1 Flexible Pixel Format 0 */
+	0x178	/* L1 Flexible Pixel Format 1 */
+};
+
+static const u64 ltdc_format_modifiers[] = {
+	DRM_FORMAT_MOD_LINEAR,
+	DRM_FORMAT_MOD_INVALID
+};
+
+static const struct regmap_config stm32_ltdc_regmap_cfg = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = sizeof(u32),
+	.max_register = 0x400,
+	.use_relaxed_mmio = true,
+	.cache_type = REGCACHE_NONE,
+};
+
+static const u32 ltdc_ycbcr2rgb_coeffs[DRM_COLOR_ENCODING_MAX][DRM_COLOR_RANGE_MAX][2] = {
+	[DRM_COLOR_YCBCR_BT601][DRM_COLOR_YCBCR_LIMITED_RANGE] = {
+		0x02040199,	/* (b_cb = 516 / r_cr = 409) */
+		0x006400D0	/* (g_cb = 100 / g_cr = 208) */
+	},
+	[DRM_COLOR_YCBCR_BT601][DRM_COLOR_YCBCR_FULL_RANGE] = {
+		0x01C60167,	/* (b_cb = 454 / r_cr = 359) */
+		0x005800B7	/* (g_cb = 88 / g_cr = 183) */
+	},
+	[DRM_COLOR_YCBCR_BT709][DRM_COLOR_YCBCR_LIMITED_RANGE] = {
+		0x021D01CB,	/* (b_cb = 541 / r_cr = 459) */
+		0x00370089	/* (g_cb = 55 / g_cr = 137) */
+	},
+	[DRM_COLOR_YCBCR_BT709][DRM_COLOR_YCBCR_FULL_RANGE] = {
+		0x01DB0193,	/* (b_cb = 475 / r_cr = 403) */
+		0x00300078	/* (g_cb = 48 / g_cr = 120) */
+	}
+	/* BT2020 not supported */
+};
+
+static inline struct ltdc_device *crtc_to_ltdc(struct drm_crtc *crtc)
+{
+	return (struct ltdc_device *)crtc->dev->dev_private;
+}
+
+static inline struct ltdc_device *plane_to_ltdc(struct drm_plane *plane)
+{
+	return (struct ltdc_device *)plane->dev->dev_private;
+}
+
+static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
+{
+	enum ltdc_pix_fmt pf;
+
+	switch (drm_fmt) {
+	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XRGB8888:
+		pf = PF_ARGB8888;
+		break;
+	case DRM_FORMAT_ABGR8888:
+	case DRM_FORMAT_XBGR8888:
+		pf = PF_ABGR8888;
+		break;
+	case DRM_FORMAT_RGBA8888:
+	case DRM_FORMAT_RGBX8888:
+		pf = PF_RGBA8888;
+		break;
+	case DRM_FORMAT_BGRA8888:
+	case DRM_FORMAT_BGRX8888:
+		pf = PF_BGRA8888;
+		break;
+	case DRM_FORMAT_RGB888:
+		pf = PF_RGB888;
+		break;
+	case DRM_FORMAT_BGR888:
+		pf = PF_BGR888;
+		break;
+	case DRM_FORMAT_RGB565:
+		pf = PF_RGB565;
+		break;
+	case DRM_FORMAT_BGR565:
+		pf = PF_BGR565;
+		break;
+	case DRM_FORMAT_ARGB1555:
+	case DRM_FORMAT_XRGB1555:
+		pf = PF_ARGB1555;
+		break;
+	case DRM_FORMAT_ARGB4444:
+	case DRM_FORMAT_XRGB4444:
+		pf = PF_ARGB4444;
+		break;
+	case DRM_FORMAT_C8:
+		pf = PF_L8;
+		break;
+	default:
+		pf = PF_NONE;
+		break;
+		/* Note: There are no DRM_FORMAT for AL44 and AL88 */
+	}
+
+	return pf;
+}
+
+static inline u32 ltdc_set_flexible_pixel_format(struct drm_plane *plane, enum ltdc_pix_fmt pix_fmt)
+{
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	u32 lofs = plane->index * LAY_OFS, ret = PF_FLEXIBLE;
+	int psize, alen, apos, rlen, rpos, glen, gpos, blen, bpos;
+
+	switch (pix_fmt) {
+	case PF_BGR888:
+		psize = 3;
+		alen = 0; apos = 0; rlen = 8; rpos = 0;
+		glen = 8; gpos = 8; blen = 8; bpos = 16;
+	break;
+	case PF_ARGB1555:
+		psize = 2;
+		alen = 1; apos = 15; rlen = 5; rpos = 10;
+		glen = 5; gpos = 5;  blen = 5; bpos = 0;
+	break;
+	case PF_ARGB4444:
+		psize = 2;
+		alen = 4; apos = 12; rlen = 4; rpos = 8;
+		glen = 4; gpos = 4; blen = 4; bpos = 0;
+	break;
+	case PF_L8:
+		psize = 1;
+		alen = 0; apos = 0; rlen = 8; rpos = 0;
+		glen = 8; gpos = 0; blen = 8; bpos = 0;
+	break;
+	case PF_AL44:
+		psize = 1;
+		alen = 4; apos = 4; rlen = 4; rpos = 0;
+		glen = 4; gpos = 0; blen = 4; bpos = 0;
+	break;
+	case PF_AL88:
+		psize = 2;
+		alen = 8; apos = 8; rlen = 8; rpos = 0;
+		glen = 8; gpos = 0; blen = 8; bpos = 0;
+	break;
+	default:
+		ret = NB_PF; /* error case, trace msg is handled by the caller */
+	break;
+	}
+
+	if (ret == PF_FLEXIBLE) {
+		regmap_write(ldev->regmap, LTDC_L1FPF0R + lofs,
+			     (rlen << 14)  + (rpos << 9) + (alen << 5) + apos);
+
+		regmap_write(ldev->regmap, LTDC_L1FPF1R + lofs,
+			     (psize << 18) + (blen << 14)  + (bpos << 9) + (glen << 5) + gpos);
+	}
+
+	return ret;
+}
+
+/*
+ * All non-alpha color formats derived from native alpha color formats are
+ * either characterized by a FourCC format code
+ */
+static inline u32 is_xrgb(u32 drm)
+{
+	return ((drm & 0xFF) == 'X' || ((drm >> 8) & 0xFF) == 'X');
+}
+
+static inline void ltdc_set_ycbcr_config(struct drm_plane *plane, u32 drm_pix_fmt)
+{
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	struct drm_plane_state *state = plane->state;
+	u32 lofs = plane->index * LAY_OFS;
+	u32 val;
+
+	switch (drm_pix_fmt) {
+	case DRM_FORMAT_YUYV:
+		val = (YCM_I << 4) | LxPCR_YF | LxPCR_CBF;
+		break;
+	case DRM_FORMAT_YVYU:
+		val = (YCM_I << 4) | LxPCR_YF;
+		break;
+	case DRM_FORMAT_UYVY:
+		val = (YCM_I << 4) | LxPCR_CBF;
+		break;
+	case DRM_FORMAT_VYUY:
+		val = (YCM_I << 4);
+		break;
+	case DRM_FORMAT_NV12:
+		val = (YCM_SP << 4) | LxPCR_CBF;
+		break;
+	case DRM_FORMAT_NV21:
+		val = (YCM_SP << 4);
+		break;
+	case DRM_FORMAT_YUV420:
+	case DRM_FORMAT_YVU420:
+		val = (YCM_FP << 4);
+		break;
+	default:
+		/* RGB or not a YCbCr supported format */
+		drm_err(plane->dev, "Unsupported pixel format: %u\n", drm_pix_fmt);
+		return;
+	}
+
+	/* Enable limited range */
+	if (state->color_range == DRM_COLOR_YCBCR_LIMITED_RANGE)
+		val |= LxPCR_YREN;
+
+	/* enable ycbcr conversion */
+	val |= LxPCR_YCEN;
+
+	regmap_write(ldev->regmap, LTDC_L1PCR + lofs, val);
+}
+
+static inline void ltdc_set_ycbcr_coeffs(struct drm_plane *plane)
+{
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	struct drm_plane_state *state = plane->state;
+	enum drm_color_encoding enc = state->color_encoding;
+	enum drm_color_range ran = state->color_range;
+	u32 lofs = plane->index * LAY_OFS;
+
+	if (enc != DRM_COLOR_YCBCR_BT601 && enc != DRM_COLOR_YCBCR_BT709) {
+		drm_err(plane->dev, "color encoding %d not supported, use bt601 by default\n", enc);
+		/* set by default color encoding to DRM_COLOR_YCBCR_BT601 */
+		enc = DRM_COLOR_YCBCR_BT601;
+	}
+
+	if (ran != DRM_COLOR_YCBCR_LIMITED_RANGE && ran != DRM_COLOR_YCBCR_FULL_RANGE) {
+		drm_err(plane->dev,
+			"color range %d not supported, use limited range by default\n", ran);
+		/* set by default color range to DRM_COLOR_YCBCR_LIMITED_RANGE */
+		ran = DRM_COLOR_YCBCR_LIMITED_RANGE;
+	}
+
+	drm_err(plane->dev, "Color encoding=%d, range=%d\n", enc, ran);
+	regmap_write(ldev->regmap, LTDC_L1CYR0R + lofs,
+		     ltdc_ycbcr2rgb_coeffs[enc][ran][0]);
+	regmap_write(ldev->regmap, LTDC_L1CYR1R + lofs,
+		     ltdc_ycbcr2rgb_coeffs[enc][ran][1]);
+}
+
+static inline void ltdc_irq_crc_handle(struct ltdc_device *ldev,
+				       struct drm_crtc *crtc)
+{
+	u32 crc;
+	int ret;
+
+	if (ldev->crc_skip_count < CRC_SKIP_FRAMES) {
+		ldev->crc_skip_count++;
+		return;
+	}
+
+	/* Get the CRC of the frame */
+	ret = regmap_read(ldev->regmap, LTDC_CCRCR, &crc);
+	if (ret)
+		return;
+
+	/* Report to DRM the CRC (hw dependent feature) */
+	drm_crtc_add_crc_entry(crtc, true, drm_crtc_accurate_vblank_count(crtc), &crc);
+}
+
+static irqreturn_t ltdc_irq_thread(int irq, void *arg)
+{
+	struct drm_device *ddev = arg;
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct drm_crtc *crtc = drm_crtc_from_index(ddev, 0);
+
+	/* Line IRQ : trigger the vblank event */
+	if (ldev->irq_status & ISR_LIF) {
+		drm_crtc_handle_vblank(crtc);
+
+		/* Early return if CRC is not active */
+		if (ldev->crc_active)
+			ltdc_irq_crc_handle(ldev, crtc);
+	}
+
+	mutex_lock(&ldev->err_lock);
+	if (ldev->irq_status & ISR_TERRIF)
+		ldev->transfer_err++;
+	if (ldev->irq_status & ISR_FUEIF)
+		ldev->fifo_err++;
+	if (ldev->irq_status & ISR_FUWIF)
+		ldev->fifo_warn++;
+	mutex_unlock(&ldev->err_lock);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t ltdc_irq(int irq, void *arg)
+{
+	struct drm_device *ddev = arg;
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	/*
+	 *  Read & Clear the interrupt status
+	 *  In order to write / read registers in this critical section
+	 *  very quickly, the regmap functions are not used.
+	 */
+	ldev->irq_status = readl_relaxed(ldev->regs + LTDC_ISR);
+	writel_relaxed(ldev->irq_status, ldev->regs + LTDC_ICR);
+
+	return IRQ_WAKE_THREAD;
+}
+
+/*
+ * DRM_CRTC
+ */
+
+static void ltdc_crtc_update_clut(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_color_lut *lut;
+	u32 val;
+	int i;
+
+	if (!crtc->state->color_mgmt_changed || !crtc->state->gamma_lut)
+		return;
+
+	lut = (struct drm_color_lut *)crtc->state->gamma_lut->data;
+
+	for (i = 0; i < CLUT_SIZE; i++, lut++) {
+		val = ((lut->red << 8) & 0xff0000) | (lut->green & 0xff00) |
+			(lut->blue >> 8) | (i << 24);
+		regmap_write(ldev->regmap, LTDC_L1CLUTWR, val);
+	}
+}
+
+static void ltdc_crtc_atomic_enable(struct drm_crtc *crtc,
+				    struct drm_atomic_commit *state)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+
+	drm_dbg_driver(crtc->dev, "\n");
+
+	pm_runtime_get_sync(ddev->dev);
+
+	/* Sets the background color value */
+	regmap_write(ldev->regmap, LTDC_BCCR, BCCR_BCBLACK);
+
+	/* Enable IRQ */
+	regmap_set_bits(ldev->regmap, LTDC_IER, IER_FUWIE | IER_FUEIE | IER_TERRIE);
+
+	/* Commit shadow registers = update planes at next vblank */
+	if (!ldev->caps.plane_reg_shadow)
+		regmap_set_bits(ldev->regmap, LTDC_SRCR, SRCR_VBR);
+
+	drm_crtc_vblank_on(crtc);
+}
+
+static void ltdc_crtc_atomic_disable(struct drm_crtc *crtc,
+				     struct drm_atomic_commit *state)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+	int layer_index = 0;
+
+	drm_dbg_driver(crtc->dev, "\n");
+
+	drm_crtc_vblank_off(crtc);
+
+	/* Disable all layers */
+	for (layer_index = 0; layer_index < ldev->caps.nb_layers; layer_index++)
+		regmap_write_bits(ldev->regmap, LTDC_L1CR + layer_index * LAY_OFS, LXCR_MASK, 0);
+
+	/* Disable IRQ */
+	regmap_clear_bits(ldev->regmap, LTDC_IER, IER_FUWIE | IER_FUEIE | IER_TERRIE);
+
+	/* immediately commit disable of layers before switching off LTDC */
+	if (!ldev->caps.plane_reg_shadow)
+		regmap_set_bits(ldev->regmap, LTDC_SRCR, SRCR_IMR);
+
+	pm_runtime_put_sync(ddev->dev);
+
+	/*  clear interrupt error counters */
+	mutex_lock(&ldev->err_lock);
+	ldev->transfer_err = 0;
+	ldev->fifo_err = 0;
+	ldev->fifo_warn = 0;
+	mutex_unlock(&ldev->err_lock);
+}
+
+#define CLK_TOLERANCE_HZ 50
+
+static enum drm_mode_status
+ltdc_crtc_mode_valid(struct drm_crtc *crtc,
+		     const struct drm_display_mode *mode)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	int target = mode->clock * 1000;
+	int target_min = target - CLK_TOLERANCE_HZ;
+	int target_max = target + CLK_TOLERANCE_HZ;
+	int result;
+
+	if (ldev->lvds_clk) {
+		result = clk_round_rate(ldev->lvds_clk, target);
+		drm_dbg_driver(crtc->dev, "lvds pixclk rate target %d, available %d\n",
+			       target, result);
+	}
+
+	result = clk_round_rate(ldev->pixel_clk, target);
+
+	drm_dbg_driver(crtc->dev, "clk rate target %d, available %d\n", target, result);
+
+	/* Filter modes according to the max frequency supported by the pads */
+	if (result > ldev->caps.pad_max_freq_hz)
+		return MODE_CLOCK_HIGH;
+
+	/*
+	 * Accept all "preferred" modes:
+	 * - this is important for panels because panel clock tolerances are
+	 *   bigger than hdmi ones and there is no reason to not accept them
+	 *   (the fps may vary a little but it is not a problem).
+	 * - the hdmi preferred mode will be accepted too, but userland will
+	 *   be able to use others hdmi "valid" modes if necessary.
+	 */
+	if (mode->type & DRM_MODE_TYPE_PREFERRED)
+		return MODE_OK;
+
+	/*
+	 * Filter modes according to the clock value, particularly useful for
+	 * hdmi modes that require precise pixel clocks.
+	 */
+	if (result < target_min || result > target_max)
+		return MODE_CLOCK_RANGE;
+
+	return MODE_OK;
+}
+
+static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
+				 const struct drm_display_mode *mode,
+				 struct drm_display_mode *adjusted_mode)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	int rate = mode->clock * 1000;
+
+	if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
+		drm_err(crtc->dev, "Cannot set rate (%dHz) for pixel clk\n", rate);
+		return false;
+	}
+
+	adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000;
+
+	drm_dbg_driver(crtc->dev, "requested clock %dkHz, adjusted clock %dkHz\n",
+		       mode->clock, adjusted_mode->clock);
+
+	return true;
+}
+
+static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+	struct drm_connector_list_iter iter;
+	struct drm_connector *connector = NULL;
+	struct drm_encoder *encoder = NULL, *en_iter;
+	struct drm_bridge *bridge = NULL, *br_iter;
+	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+	u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
+	u32 total_width, total_height;
+	u32 bus_formats = MEDIA_BUS_FMT_RGB888_1X24;
+	u32 bus_flags = 0;
+	u32 val;
+	int ret;
+
+	/* get encoder from crtc */
+	drm_for_each_encoder(en_iter, ddev)
+		if (en_iter->crtc == crtc) {
+			encoder = en_iter;
+			break;
+		}
+
+	if (encoder) {
+		/* get bridge from encoder */
+		list_for_each_entry(br_iter, &encoder->bridge_chain, chain_node)
+			if (br_iter->encoder == encoder) {
+				bridge = br_iter;
+				break;
+			}
+
+		/* Get the connector from encoder */
+		drm_connector_list_iter_begin(ddev, &iter);
+		drm_for_each_connector_iter(connector, &iter)
+			if (connector->encoder == encoder)
+				break;
+		drm_connector_list_iter_end(&iter);
+	}
+
+	if (bridge && bridge->timings) {
+		bus_flags = bridge->timings->input_bus_flags;
+	} else if (connector) {
+		bus_flags = connector->display_info.bus_flags;
+		if (connector->display_info.num_bus_formats)
+			bus_formats = connector->display_info.bus_formats[0];
+	}
+
+	if (!pm_runtime_active(ddev->dev)) {
+		ret = pm_runtime_get_sync(ddev->dev);
+		if (ret) {
+			drm_err(crtc->dev, "Failed to set mode, cannot get sync\n");
+			return;
+		}
+	}
+
+	drm_dbg_driver(crtc->dev, "CRTC:%d mode:%s\n", crtc->base.id, mode->name);
+	drm_dbg_driver(crtc->dev, "Video mode: %dx%d", mode->hdisplay, mode->vdisplay);
+	drm_dbg_driver(crtc->dev, " hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
+		       mode->hsync_start - mode->hdisplay,
+		       mode->htotal - mode->hsync_end,
+		       mode->hsync_end - mode->hsync_start,
+		       mode->vsync_start - mode->vdisplay,
+		       mode->vtotal - mode->vsync_end,
+		       mode->vsync_end - mode->vsync_start);
+
+	/* Convert video timings to ltdc timings */
+	hsync = mode->hsync_end - mode->hsync_start - 1;
+	vsync = mode->vsync_end - mode->vsync_start - 1;
+	accum_hbp = mode->htotal - mode->hsync_start - 1;
+	accum_vbp = mode->vtotal - mode->vsync_start - 1;
+	accum_act_w = accum_hbp + mode->hdisplay;
+	accum_act_h = accum_vbp + mode->vdisplay;
+	total_width = mode->htotal - 1;
+	total_height = mode->vtotal - 1;
+
+	/* Configures the HS, VS, DE and PC polarities. Default Active Low */
+	val = 0;
+
+	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
+		val |= GCR_HSPOL;
+
+	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
+		val |= GCR_VSPOL;
+
+	if (bus_flags & DRM_BUS_FLAG_DE_LOW)
+		val |= GCR_DEPOL;
+
+	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
+		val |= GCR_PCPOL;
+
+	regmap_update_bits(ldev->regmap, LTDC_GCR,
+			   GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
+
+	/* Set Synchronization size */
+	val = (hsync << 16) | vsync;
+	regmap_update_bits(ldev->regmap, LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
+
+	/* Set Accumulated Back porch */
+	val = (accum_hbp << 16) | accum_vbp;
+	regmap_update_bits(ldev->regmap, LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
+
+	/* Set Accumulated Active Width */
+	val = (accum_act_w << 16) | accum_act_h;
+	regmap_update_bits(ldev->regmap, LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
+
+	/* Set total width & height */
+	val = (total_width << 16) | total_height;
+	regmap_update_bits(ldev->regmap, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
+
+	regmap_write(ldev->regmap, LTDC_LIPCR, (accum_act_h + 1));
+
+	/* Configure the output format (hw version dependent) */
+	if (ldev->caps.ycbcr_output) {
+		/* Input video dynamic_range & colorimetry */
+		int vic = drm_match_cea_mode(mode);
+		u32 val;
+
+		if (vic == 6 || vic == 7 || vic == 21 || vic == 22 ||
+		    vic == 2 || vic == 3 || vic == 17 || vic == 18)
+			/* ITU-R BT.601 */
+			val = 0;
+		else
+			/* ITU-R BT.709 */
+			val = EDCR_OCYSEL;
+
+		switch (bus_formats) {
+		case MEDIA_BUS_FMT_YUYV8_1X16:
+			/* enable ycbcr output converter */
+			regmap_write(ldev->regmap, LTDC_EDCR, EDCR_OCYEN | val);
+			break;
+		case MEDIA_BUS_FMT_YVYU8_1X16:
+			/* enable ycbcr output converter & invert chrominance order */
+			regmap_write(ldev->regmap, LTDC_EDCR, EDCR_OCYEN | EDCR_OCYCO | val);
+			break;
+		default:
+			/* disable ycbcr output converter */
+			regmap_write(ldev->regmap, LTDC_EDCR, 0);
+			break;
+		}
+	}
+}
+
+static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
+				   struct drm_atomic_commit *state)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_device *ddev = crtc->dev;
+	struct drm_pending_vblank_event *event = crtc->state->event;
+
+	drm_dbg_atomic(crtc->dev, "\n");
+
+	ltdc_crtc_update_clut(crtc);
+
+	/* Commit shadow registers = update planes at next vblank */
+	if (!ldev->caps.plane_reg_shadow)
+		regmap_set_bits(ldev->regmap, LTDC_SRCR, SRCR_VBR);
+
+	if (event) {
+		crtc->state->event = NULL;
+
+		spin_lock_irq(&ddev->event_lock);
+		if (drm_crtc_vblank_get(crtc) == 0)
+			drm_crtc_arm_vblank_event(crtc, event);
+		else
+			drm_crtc_send_vblank_event(crtc, event);
+		spin_unlock_irq(&ddev->event_lock);
+	}
+}
+
+static bool ltdc_crtc_get_scanout_position(struct drm_crtc *crtc,
+					   bool in_vblank_irq,
+					   int *vpos, int *hpos,
+					   ktime_t *stime, ktime_t *etime,
+					   const struct drm_display_mode *mode)
+{
+	struct drm_device *ddev = crtc->dev;
+	struct ltdc_device *ldev = ddev->dev_private;
+	int line, vactive_start, vactive_end, vtotal;
+
+	if (stime)
+		*stime = ktime_get();
+
+	/* The active area starts after vsync + front porch and ends
+	 * at vsync + front porc + display size.
+	 * The total height also include back porch.
+	 * We have 3 possible cases to handle:
+	 * - line < vactive_start: vpos = line - vactive_start and will be
+	 * negative
+	 * - vactive_start < line < vactive_end: vpos = line - vactive_start
+	 * and will be positive
+	 * - line > vactive_end: vpos = line - vtotal - vactive_start
+	 * and will negative
+	 *
+	 * Computation for the two first cases are identical so we can
+	 * simplify the code and only test if line > vactive_end
+	 */
+	if (pm_runtime_active(ddev->dev)) {
+		regmap_read(ldev->regmap, LTDC_CPSR, &line);
+		line &= CPSR_CYPOS;
+		regmap_read(ldev->regmap, LTDC_BPCR, &vactive_start);
+		vactive_start &= BPCR_AVBP;
+		regmap_read(ldev->regmap, LTDC_AWCR, &vactive_end);
+		vactive_end &= AWCR_AAH;
+		regmap_read(ldev->regmap, LTDC_TWCR, &vtotal);
+		vtotal &= TWCR_TOTALH;
+
+		if (line > vactive_end)
+			*vpos = line - vtotal - vactive_start;
+		else
+			*vpos = line - vactive_start;
+	} else {
+		*vpos = 0;
+	}
+
+	*hpos = 0;
+
+	if (etime)
+		*etime = ktime_get();
+
+	return true;
+}
+
+static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
+	.mode_valid = ltdc_crtc_mode_valid,
+	.mode_fixup = ltdc_crtc_mode_fixup,
+	.mode_set_nofb = ltdc_crtc_mode_set_nofb,
+	.atomic_flush = ltdc_crtc_atomic_flush,
+	.atomic_enable = ltdc_crtc_atomic_enable,
+	.atomic_disable = ltdc_crtc_atomic_disable,
+	.get_scanout_position = ltdc_crtc_get_scanout_position,
+};
+
+static int ltdc_crtc_enable_vblank(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_crtc_state *state = crtc->state;
+
+	drm_dbg_driver(crtc->dev, "\n");
+
+	if (state->enable)
+		regmap_set_bits(ldev->regmap, LTDC_IER, IER_LIE);
+	else
+		return -EPERM;
+
+	return 0;
+}
+
+static void ltdc_crtc_disable_vblank(struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+
+	drm_dbg_driver(crtc->dev, "\n");
+	regmap_clear_bits(ldev->regmap, LTDC_IER, IER_LIE);
+}
+
+static int ltdc_crtc_set_crc_source(struct drm_crtc *crtc, const char *source)
+{
+	struct ltdc_device *ldev;
+	int ret;
+
+	if (!crtc)
+		return -ENODEV;
+
+	drm_dbg_driver(crtc->dev, "\n");
+
+	ldev = crtc_to_ltdc(crtc);
+
+	if (source && strcmp(source, "auto") == 0) {
+		ldev->crc_active = true;
+		ret = regmap_set_bits(ldev->regmap, LTDC_GCR, GCR_CRCEN);
+	} else if (!source) {
+		ldev->crc_active = false;
+		ret = regmap_clear_bits(ldev->regmap, LTDC_GCR, GCR_CRCEN);
+	} else {
+		ret = -EINVAL;
+	}
+
+	ldev->crc_skip_count = 0;
+	return ret;
+}
+
+static int ltdc_crtc_verify_crc_source(struct drm_crtc *crtc,
+				       const char *source, size_t *values_cnt)
+{
+	if (!crtc)
+		return -ENODEV;
+
+	drm_dbg_driver(crtc->dev, "\n");
+
+	if (source && strcmp(source, "auto") != 0) {
+		drm_dbg_driver(crtc->dev, "Unknown CRC source %s for %s\n",
+			       source, crtc->name);
+		return -EINVAL;
+	}
+
+	*values_cnt = 1;
+	return 0;
+}
+
+static void ltdc_crtc_atomic_print_state(struct drm_printer *p,
+					 const struct drm_crtc_state *state)
+{
+	struct drm_crtc *crtc = state->crtc;
+	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+
+	drm_printf(p, "\ttransfer_error=%d\n", ldev->transfer_err);
+	drm_printf(p, "\tfifo_underrun_error=%d\n", ldev->fifo_err);
+	drm_printf(p, "\tfifo_underrun_warning=%d\n", ldev->fifo_warn);
+	drm_printf(p, "\tfifo_underrun_threshold=%d\n", ldev->fifo_threshold);
+}
+
+static const struct drm_crtc_funcs ltdc_crtc_funcs = {
+	.set_config = drm_atomic_helper_set_config,
+	.page_flip = drm_atomic_helper_page_flip,
+	.reset = drm_atomic_helper_crtc_reset,
+	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.enable_vblank = ltdc_crtc_enable_vblank,
+	.disable_vblank = ltdc_crtc_disable_vblank,
+	.get_vblank_timestamp = drm_crtc_vblank_helper_get_vblank_timestamp,
+	.atomic_print_state = ltdc_crtc_atomic_print_state,
+};
+
+static const struct drm_crtc_funcs ltdc_crtc_with_crc_support_funcs = {
+	.set_config = drm_atomic_helper_set_config,
+	.page_flip = drm_atomic_helper_page_flip,
+	.reset = drm_atomic_helper_crtc_reset,
+	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.enable_vblank = ltdc_crtc_enable_vblank,
+	.disable_vblank = ltdc_crtc_disable_vblank,
+	.get_vblank_timestamp = drm_crtc_vblank_helper_get_vblank_timestamp,
+	.set_crc_source = ltdc_crtc_set_crc_source,
+	.verify_crc_source = ltdc_crtc_verify_crc_source,
+	.atomic_print_state = ltdc_crtc_atomic_print_state,
+};
+
+/*
+ * DRM_PLANE
+ */
+
+static int ltdc_plane_atomic_check(struct drm_plane *plane,
+				   struct drm_atomic_commit *state)
+{
+	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state,
+										 plane);
+	struct drm_framebuffer *fb = new_plane_state->fb;
+	u32 src_w, src_h;
+
+	drm_dbg_driver(plane->dev, "\n");
+
+	if (!fb)
+		return 0;
+
+	/* convert src_ from 16:16 format */
+	src_w = new_plane_state->src_w >> 16;
+	src_h = new_plane_state->src_h >> 16;
+
+	/* Reject scaling */
+	if (src_w != new_plane_state->crtc_w || src_h != new_plane_state->crtc_h) {
+		drm_dbg_driver(plane->dev, "Scaling is not supported");
+
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void ltdc_plane_atomic_update(struct drm_plane *plane,
+				     struct drm_atomic_commit *state)
+{
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state,
+									  plane);
+	struct drm_framebuffer *fb = newstate->fb;
+	u32 lofs = plane->index * LAY_OFS;
+	u32 x0 = newstate->crtc_x;
+	u32 x1 = newstate->crtc_x + newstate->crtc_w - 1;
+	u32 y0 = newstate->crtc_y;
+	u32 y1 = newstate->crtc_y + newstate->crtc_h - 1;
+	u32 src_x, src_y, src_w, src_h;
+	u32 val, pitch_in_bytes, line_length, line_number, ahbp, avbp, bpcr;
+	u32 paddr, paddr1, paddr2;
+	enum ltdc_pix_fmt pf;
+
+	if (!newstate->crtc || !fb) {
+		drm_dbg_driver(plane->dev, "fb or crtc NULL");
+		return;
+	}
+
+	/* convert src_ from 16:16 format */
+	src_x = newstate->src_x >> 16;
+	src_y = newstate->src_y >> 16;
+	src_w = newstate->src_w >> 16;
+	src_h = newstate->src_h >> 16;
+
+	drm_dbg_driver(plane->dev, "plane:%d fb:%d (%dx%d)@(%d,%d) -> (%dx%d)@(%d,%d)\n",
+		       plane->base.id, fb->base.id,
+		       src_w, src_h, src_x, src_y,
+		       newstate->crtc_w, newstate->crtc_h,
+		       newstate->crtc_x, newstate->crtc_y);
+
+	regmap_read(ldev->regmap, LTDC_BPCR, &bpcr);
+
+	ahbp = (bpcr & BPCR_AHBP) >> 16;
+	avbp = bpcr & BPCR_AVBP;
+
+	/* Configures the horizontal start and stop position */
+	val = ((x1 + 1 + ahbp) << 16) + (x0 + 1 + ahbp);
+	regmap_write_bits(ldev->regmap, LTDC_L1WHPCR + lofs,
+			  LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS, val);
+
+	/* Configures the vertical start and stop position */
+	val = ((y1 + 1 + avbp) << 16) + (y0 + 1 + avbp);
+	regmap_write_bits(ldev->regmap, LTDC_L1WVPCR + lofs,
+			  LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS, val);
+
+	/* Specifies the pixel format */
+	pf = to_ltdc_pixelformat(fb->format->format);
+	for (val = 0; val < NB_PF; val++)
+		if (ldev->caps.pix_fmt_hw[val] == pf)
+			break;
+
+	/* Use the flexible color format feature if necessary and available */
+	if (ldev->caps.pix_fmt_flex && val == NB_PF)
+		val = ltdc_set_flexible_pixel_format(plane, pf);
+
+	if (val == NB_PF) {
+		drm_err(fb->dev, "Pixel format %.4s not supported\n",
+			(char *)&fb->format->format);
+		val = 0;	/* set by default ARGB 32 bits */
+	}
+	regmap_write_bits(ldev->regmap, LTDC_L1PFCR + lofs, LXPFCR_PF, val);
+
+	/* Specifies the constant alpha value */
+	val = newstate->alpha >> 8;
+	regmap_write_bits(ldev->regmap, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
+
+	/* Specifies the blending factors */
+	val = BF1_PAXCA | BF2_1PAXCA;
+	if (!fb->format->has_alpha)
+		val = BF1_CA | BF2_1CA;
+
+	/* Manage hw-specific capabilities */
+	if (ldev->caps.non_alpha_only_l1 &&
+	    plane->type != DRM_PLANE_TYPE_PRIMARY)
+		val = BF1_PAXCA | BF2_1PAXCA;
+
+	if (ldev->caps.dynamic_zorder) {
+		val |= (newstate->normalized_zpos << 16);
+		regmap_write_bits(ldev->regmap, LTDC_L1BFCR + lofs,
+				  LXBFCR_BF2 | LXBFCR_BF1 | LXBFCR_BOR, val);
+	} else {
+		regmap_write_bits(ldev->regmap, LTDC_L1BFCR + lofs,
+				  LXBFCR_BF2 | LXBFCR_BF1, val);
+	}
+
+	/* Sets the FB address */
+	paddr = (u32)drm_fb_dma_get_gem_addr(fb, newstate, 0);
+
+	if (newstate->rotation & DRM_MODE_REFLECT_X)
+		paddr += (fb->format->cpp[0] * (x1 - x0 + 1)) - 1;
+
+	if (newstate->rotation & DRM_MODE_REFLECT_Y)
+		paddr += (fb->pitches[0] * (y1 - y0));
+
+	drm_dbg_driver(fb->dev, "fb: phys 0x%08x", paddr);
+	regmap_write(ldev->regmap, LTDC_L1CFBAR + lofs, paddr);
+
+	/* Configures the color frame buffer pitch in bytes & line length */
+	line_length = fb->format->cpp[0] *
+		      (x1 - x0 + 1) + (ldev->caps.bus_width >> 3) - 1;
+
+	if (newstate->rotation & DRM_MODE_REFLECT_Y)
+		/* Compute negative value (signed on 16 bits) for the picth */
+		pitch_in_bytes = 0x10000 - fb->pitches[0];
+	else
+		pitch_in_bytes = fb->pitches[0];
+
+	val = (pitch_in_bytes << 16) | line_length;
+	regmap_write_bits(ldev->regmap, LTDC_L1CFBLR + lofs, LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
+
+	/* Configures the frame buffer line number */
+	line_number = y1 - y0 + 1;
+	regmap_write_bits(ldev->regmap, LTDC_L1CFBLNR + lofs, LXCFBLNR_CFBLN, line_number);
+
+	if (ldev->caps.ycbcr_input) {
+		if (fb->format->is_yuv) {
+			switch (fb->format->format) {
+			case DRM_FORMAT_NV12:
+			case DRM_FORMAT_NV21:
+			/* Configure the auxiliary frame buffer address 0 */
+			paddr1 = (u32)drm_fb_dma_get_gem_addr(fb, newstate, 1);
+
+			if (newstate->rotation & DRM_MODE_REFLECT_X)
+				paddr1 += ((fb->format->cpp[1] * (x1 - x0 + 1)) >> 1) - 1;
+
+			if (newstate->rotation & DRM_MODE_REFLECT_Y)
+				paddr1 += (fb->pitches[1] * (y1 - y0 - 1)) >> 1;
+
+			regmap_write(ldev->regmap, LTDC_L1AFBA0R + lofs, paddr1);
+			break;
+			case DRM_FORMAT_YUV420:
+			/* Configure the auxiliary frame buffer address 0 & 1 */
+			paddr1 = (u32)drm_fb_dma_get_gem_addr(fb, newstate, 1);
+			paddr2 = (u32)drm_fb_dma_get_gem_addr(fb, newstate, 2);
+
+			if (newstate->rotation & DRM_MODE_REFLECT_X) {
+				paddr1 += ((fb->format->cpp[1] * (x1 - x0 + 1)) >> 1) - 1;
+				paddr2 += ((fb->format->cpp[2] * (x1 - x0 + 1)) >> 1) - 1;
+			}
+
+			if (newstate->rotation & DRM_MODE_REFLECT_Y) {
+				paddr1 += (fb->pitches[1] * (y1 - y0 - 1)) >> 1;
+				paddr2 += (fb->pitches[2] * (y1 - y0 - 1)) >> 1;
+			}
+
+			regmap_write(ldev->regmap, LTDC_L1AFBA0R + lofs, paddr1);
+			regmap_write(ldev->regmap, LTDC_L1AFBA1R + lofs, paddr2);
+			break;
+			case DRM_FORMAT_YVU420:
+			/* Configure the auxiliary frame buffer address 0 & 1 */
+			paddr1 = (u32)drm_fb_dma_get_gem_addr(fb, newstate, 2);
+			paddr2 = (u32)drm_fb_dma_get_gem_addr(fb, newstate, 1);
+
+			if (newstate->rotation & DRM_MODE_REFLECT_X) {
+				paddr1 += ((fb->format->cpp[1] * (x1 - x0 + 1)) >> 1) - 1;
+				paddr2 += ((fb->format->cpp[2] * (x1 - x0 + 1)) >> 1) - 1;
+			}
+
+			if (newstate->rotation & DRM_MODE_REFLECT_Y) {
+				paddr1 += (fb->pitches[1] * (y1 - y0 - 1)) >> 1;
+				paddr2 += (fb->pitches[2] * (y1 - y0 - 1)) >> 1;
+			}
+
+			regmap_write(ldev->regmap, LTDC_L1AFBA0R + lofs, paddr1);
+			regmap_write(ldev->regmap, LTDC_L1AFBA1R + lofs, paddr2);
+			break;
+			}
+
+			/*
+			 * Set the length and the number of lines of the auxiliary
+			 * buffers if the framebuffer contains more than one plane.
+			 */
+			if (fb->format->num_planes > 1) {
+				if (newstate->rotation & DRM_MODE_REFLECT_Y)
+					/*
+					 * Compute negative value (signed on 16 bits)
+					 * for the picth
+					 */
+					pitch_in_bytes = 0x10000 - fb->pitches[1];
+				else
+					pitch_in_bytes = fb->pitches[1];
+
+				line_length = ((fb->format->cpp[1] * (x1 - x0 + 1)) >> 1) +
+					      (ldev->caps.bus_width >> 3) - 1;
+
+				/* Configure the auxiliary buffer length */
+				val = (pitch_in_bytes << 16) | line_length;
+				regmap_write(ldev->regmap, LTDC_L1AFBLR + lofs, val);
+
+				/* Configure the auxiliary frame buffer line number */
+				val = line_number >> 1;
+				regmap_write(ldev->regmap, LTDC_L1AFBLNR + lofs, val);
+			}
+
+			/* Configure YCbC conversion coefficient */
+			ltdc_set_ycbcr_coeffs(plane);
+
+			/* Configure YCbCr format and enable/disable conversion */
+			ltdc_set_ycbcr_config(plane, fb->format->format);
+		} else {
+			/* disable ycbcr conversion */
+			regmap_write(ldev->regmap, LTDC_L1PCR + lofs, 0);
+		}
+	}
+
+	/* Enable layer and CLUT if needed */
+	val = fb->format->format == DRM_FORMAT_C8 ? LXCR_CLUTEN : 0;
+	val |= LXCR_LEN;
+
+	/* Enable horizontal mirroring if requested */
+	if (newstate->rotation & DRM_MODE_REFLECT_X)
+		val |= LXCR_HMEN;
+
+	regmap_write_bits(ldev->regmap, LTDC_L1CR + lofs, LXCR_MASK, val);
+
+	/* Commit shadow registers = update plane at next vblank */
+	if (ldev->caps.plane_reg_shadow)
+		regmap_write_bits(ldev->regmap, LTDC_L1RCR + lofs,
+				  LXRCR_IMR | LXRCR_VBR | LXRCR_GRMSK, LXRCR_VBR);
+
+	ldev->plane_fpsi[plane->index].counter++;
+
+	mutex_lock(&ldev->err_lock);
+	if (ldev->transfer_err) {
+		DRM_WARN("ltdc transfer error: %d\n", ldev->transfer_err);
+		ldev->transfer_err = 0;
+	}
+
+	if (ldev->caps.fifo_threshold) {
+		if (ldev->fifo_err) {
+			DRM_WARN("ltdc fifo underrun: please verify display mode\n");
+			ldev->fifo_err = 0;
+		}
+	} else {
+		if (ldev->fifo_warn >= ldev->fifo_threshold) {
+			DRM_WARN("ltdc fifo underrun: please verify display mode\n");
+			ldev->fifo_warn = 0;
+		}
+	}
+	mutex_unlock(&ldev->err_lock);
+}
+
+static void ltdc_plane_atomic_disable(struct drm_plane *plane,
+				      struct drm_atomic_commit *state)
+{
+	struct drm_plane_state *oldstate = drm_atomic_get_old_plane_state(state,
+									  plane);
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	u32 lofs = plane->index * LAY_OFS;
+
+	/* Disable layer */
+	regmap_write_bits(ldev->regmap, LTDC_L1CR + lofs, LXCR_MASK, 0);
+
+	/* Reset the layer transparency to hide any related background color */
+	regmap_write_bits(ldev->regmap, LTDC_L1CACR + lofs, LXCACR_CONSTA, 0x00);
+
+	/* Commit shadow registers = update plane at next vblank */
+	if (ldev->caps.plane_reg_shadow)
+		regmap_write_bits(ldev->regmap, LTDC_L1RCR + lofs,
+				  LXRCR_IMR | LXRCR_VBR | LXRCR_GRMSK, LXRCR_VBR);
+
+	drm_dbg_driver(plane->dev, "CRTC:%d plane:%d\n",
+		       oldstate->crtc->base.id, plane->base.id);
+}
+
+static void ltdc_plane_atomic_print_state(struct drm_printer *p,
+					  const struct drm_plane_state *state)
+{
+	struct drm_plane *plane = state->plane;
+	struct ltdc_device *ldev = plane_to_ltdc(plane);
+	struct fps_info *fpsi = &ldev->plane_fpsi[plane->index];
+	int ms_since_last;
+	ktime_t now;
+
+	now = ktime_get();
+	ms_since_last = ktime_to_ms(ktime_sub(now, fpsi->last_timestamp));
+
+	drm_printf(p, "\tuser_updates=%dfps\n",
+		   DIV_ROUND_CLOSEST(fpsi->counter * 1000, ms_since_last));
+
+	fpsi->last_timestamp = now;
+	fpsi->counter = 0;
+}
+
+static const struct drm_plane_funcs ltdc_plane_funcs = {
+	.update_plane = drm_atomic_helper_update_plane,
+	.disable_plane = drm_atomic_helper_disable_plane,
+	.reset = drm_atomic_helper_plane_reset,
+	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
+	.atomic_print_state = ltdc_plane_atomic_print_state,
+};
+
+static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {
+	.atomic_check = ltdc_plane_atomic_check,
+	.atomic_update = ltdc_plane_atomic_update,
+	.atomic_disable = ltdc_plane_atomic_disable,
+};
+
+static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
+					   enum drm_plane_type type,
+					   int index)
+{
+	unsigned long possible_crtcs = CRTC_MASK;
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct device *dev = ddev->dev;
+	struct drm_plane *plane;
+	unsigned int i, nb_fmt = 0;
+	u32 *formats;
+	u32 drm_fmt;
+	const u64 *modifiers = ltdc_format_modifiers;
+	u32 lofs = index * LAY_OFS;
+	u32 val;
+
+	/* Allocate the biggest size according to supported color formats */
+	formats = devm_kzalloc(dev, (ldev->caps.pix_fmt_nb +
+			       ARRAY_SIZE(ltdc_drm_fmt_ycbcr_cp) +
+			       ARRAY_SIZE(ltdc_drm_fmt_ycbcr_sp) +
+			       ARRAY_SIZE(ltdc_drm_fmt_ycbcr_fp)) *
+			       sizeof(*formats), GFP_KERNEL);
+	if (!formats)
+		return NULL;
+
+	for (i = 0; i < ldev->caps.pix_fmt_nb; i++) {
+		drm_fmt = ldev->caps.pix_fmt_drm[i];
+
+		/* Manage hw-specific capabilities */
+		if (ldev->caps.non_alpha_only_l1)
+			/* XR24 & RX24 like formats supported only on primary layer */
+			if (type != DRM_PLANE_TYPE_PRIMARY && is_xrgb(drm_fmt))
+				continue;
+
+		formats[nb_fmt++] = drm_fmt;
+	}
+
+	/* Add YCbCr supported pixel formats */
+	if (ldev->caps.ycbcr_input) {
+		regmap_read(ldev->regmap, LTDC_L1C1R + lofs, &val);
+		if (val & LXCR_C1R_YIA) {
+			memcpy(&formats[nb_fmt], ltdc_drm_fmt_ycbcr_cp,
+			       ARRAY_SIZE(ltdc_drm_fmt_ycbcr_cp) * sizeof(*formats));
+			nb_fmt += ARRAY_SIZE(ltdc_drm_fmt_ycbcr_cp);
+		}
+		if (val & LXCR_C1R_YSPA) {
+			memcpy(&formats[nb_fmt], ltdc_drm_fmt_ycbcr_sp,
+			       ARRAY_SIZE(ltdc_drm_fmt_ycbcr_sp) * sizeof(*formats));
+			nb_fmt += ARRAY_SIZE(ltdc_drm_fmt_ycbcr_sp);
+		}
+		if (val & LXCR_C1R_YFPA) {
+			memcpy(&formats[nb_fmt], ltdc_drm_fmt_ycbcr_fp,
+			       ARRAY_SIZE(ltdc_drm_fmt_ycbcr_fp) * sizeof(*formats));
+			nb_fmt += ARRAY_SIZE(ltdc_drm_fmt_ycbcr_fp);
+		}
+	}
+
+	plane = drmm_universal_plane_alloc(ddev, struct drm_plane, dev,
+					   possible_crtcs, &ltdc_plane_funcs, formats,
+					   nb_fmt, modifiers, type, NULL);
+	if (IS_ERR(plane))
+		return NULL;
+
+	if (ldev->caps.ycbcr_input) {
+		if (val & (LXCR_C1R_YIA | LXCR_C1R_YSPA | LXCR_C1R_YFPA))
+			drm_plane_create_color_properties(plane,
+							  BIT(DRM_COLOR_YCBCR_BT601) |
+							  BIT(DRM_COLOR_YCBCR_BT709),
+							  BIT(DRM_COLOR_YCBCR_LIMITED_RANGE) |
+							  BIT(DRM_COLOR_YCBCR_FULL_RANGE),
+							  DRM_COLOR_YCBCR_BT601,
+							  DRM_COLOR_YCBCR_LIMITED_RANGE);
+	}
+
+	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
+
+	drm_plane_create_alpha_property(plane);
+
+	drm_dbg_driver(plane->dev, "plane:%d created\n", plane->base.id);
+
+	return plane;
+}
+
+static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct drm_plane *primary, *overlay;
+	int supported_rotations = DRM_MODE_ROTATE_0 | DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y;
+	unsigned int i;
+	int ret;
+
+	primary = ltdc_plane_create(ddev, DRM_PLANE_TYPE_PRIMARY, 0);
+	if (!primary) {
+		drm_err(ddev, "Can not create primary plane\n");
+		return -EINVAL;
+	}
+
+	if (ldev->caps.dynamic_zorder)
+		drm_plane_create_zpos_property(primary, 0, 0, ldev->caps.nb_layers - 1);
+	else
+		drm_plane_create_zpos_immutable_property(primary, 0);
+
+	if (ldev->caps.plane_rotation)
+		drm_plane_create_rotation_property(primary, DRM_MODE_ROTATE_0,
+						   supported_rotations);
+
+	/* Init CRTC according to its hardware features */
+	if (ldev->caps.crc)
+		ret = drmm_crtc_init_with_planes(ddev, crtc, primary, NULL,
+						 &ltdc_crtc_with_crc_support_funcs, NULL);
+	else
+		ret = drmm_crtc_init_with_planes(ddev, crtc, primary, NULL,
+						 &ltdc_crtc_funcs, NULL);
+	if (ret) {
+		drm_err(ddev, "Can not initialize CRTC\n");
+		return ret;
+	}
+
+	drm_crtc_helper_add(crtc, &ltdc_crtc_helper_funcs);
+
+	drm_mode_crtc_set_gamma_size(crtc, CLUT_SIZE);
+	drm_crtc_enable_color_mgmt(crtc, 0, false, CLUT_SIZE);
+
+	drm_dbg_driver(ddev, "CRTC:%d created\n", crtc->base.id);
+
+	/* Add planes. Note : the first layer is used by primary plane */
+	for (i = 1; i < ldev->caps.nb_layers; i++) {
+		overlay = ltdc_plane_create(ddev, DRM_PLANE_TYPE_OVERLAY, i);
+		if (!overlay) {
+			drm_err(ddev, "Can not create overlay plane %d\n", i);
+			return -ENOMEM;
+		}
+		if (ldev->caps.dynamic_zorder)
+			drm_plane_create_zpos_property(overlay, i, 0, ldev->caps.nb_layers - 1);
+		else
+			drm_plane_create_zpos_immutable_property(overlay, i);
+
+		if (ldev->caps.plane_rotation)
+			drm_plane_create_rotation_property(overlay, DRM_MODE_ROTATE_0,
+							   supported_rotations);
+	}
+
+	return 0;
+}
+
+static void ltdc_encoder_disable(struct drm_encoder *encoder)
+{
+	struct drm_device *ddev = encoder->dev;
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	drm_dbg_driver(encoder->dev, "\n");
+
+	/* Disable LTDC */
+	regmap_clear_bits(ldev->regmap, LTDC_GCR, GCR_LTDCEN);
+
+	/* Set to sleep state the pinctrl whatever type of encoder */
+	pinctrl_pm_select_sleep_state(ddev->dev);
+}
+
+static void ltdc_encoder_enable(struct drm_encoder *encoder)
+{
+	struct drm_device *ddev = encoder->dev;
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	drm_dbg_driver(encoder->dev, "\n");
+
+	/* set fifo underrun threshold register */
+	if (ldev->caps.fifo_threshold)
+		regmap_write(ldev->regmap, LTDC_FUT, ldev->fifo_threshold);
+
+	/* Enable LTDC */
+	regmap_set_bits(ldev->regmap, LTDC_GCR, GCR_LTDCEN);
+}
+
+static void ltdc_encoder_mode_set(struct drm_encoder *encoder,
+				  struct drm_display_mode *mode,
+				  struct drm_display_mode *adjusted_mode)
+{
+	struct drm_device *ddev = encoder->dev;
+
+	drm_dbg_driver(encoder->dev, "\n");
+
+	/*
+	 * Set to default state the pinctrl only with DPI type.
+	 * Others types like DSI, don't need pinctrl due to
+	 * internal bridge (the signals do not come out of the chipset).
+	 */
+	if (encoder->encoder_type == DRM_MODE_ENCODER_DPI)
+		pinctrl_pm_select_default_state(ddev->dev);
+}
+
+static const struct drm_encoder_helper_funcs ltdc_encoder_helper_funcs = {
+	.disable = ltdc_encoder_disable,
+	.enable = ltdc_encoder_enable,
+	.mode_set = ltdc_encoder_mode_set,
+};
+
+static int ltdc_encoder_init(struct drm_device *ddev, struct drm_bridge *bridge)
+{
+	struct drm_encoder *encoder;
+	int ret;
+
+	encoder = drmm_simple_encoder_alloc(ddev, struct drm_encoder, dev,
+					    DRM_MODE_ENCODER_DPI);
+	if (IS_ERR(encoder))
+		return PTR_ERR(encoder);
+
+	encoder->possible_crtcs = CRTC_MASK;
+	encoder->possible_clones = 0;	/* No cloning support */
+
+	drm_encoder_helper_add(encoder, &ltdc_encoder_helper_funcs);
+
+	ret = drm_bridge_attach(encoder, bridge, NULL, 0);
+	if (ret)
+		return ret;
+
+	drm_dbg_driver(encoder->dev, "Bridge encoder:%d created\n", encoder->base.id);
+
+	return 0;
+}
+
+static int ltdc_get_caps(struct drm_device *ddev)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+	u32 bus_width_log2, lcr, gc2r;
+	const struct ltdc_plat_data *pdata = of_device_get_match_data(ddev->dev);
+
+	/*
+	 * at least 1 layer must be managed & the number of layers
+	 * must not exceed LTDC_MAX_LAYER
+	 */
+	regmap_read(ldev->regmap, LTDC_LCR, &lcr);
+
+	ldev->caps.nb_layers = clamp((int)lcr, 1, LTDC_MAX_LAYER);
+
+	/* set data bus width */
+	regmap_read(ldev->regmap, LTDC_GC2R, &gc2r);
+	bus_width_log2 = (gc2r & GC2R_BW) >> 4;
+	ldev->caps.bus_width = 8 << bus_width_log2;
+	regmap_read(ldev->regmap, LTDC_IDR, &ldev->caps.hw_version);
+
+	ldev->caps.pad_max_freq_hz = pdata->pad_max_freq_hz;
+
+	switch (ldev->caps.hw_version) {
+	case HWVER_10200:
+	case HWVER_10300:
+		ldev->caps.layer_ofs = LAY_OFS_0;
+		ldev->caps.layer_regs = ltdc_layer_regs_a0;
+		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
+		ldev->caps.pix_fmt_drm = ltdc_drm_fmt_a0;
+		ldev->caps.pix_fmt_nb = ARRAY_SIZE(ltdc_drm_fmt_a0);
+		ldev->caps.pix_fmt_flex = false;
+		/*
+		 * Hw older versions support non-alpha color formats derived
+		 * from native alpha color formats only on the primary layer.
+		 * For instance, RG16 native format without alpha works fine
+		 * on 2nd layer but XR24 (derived color format from AR24)
+		 * does not work on 2nd layer.
+		 */
+		ldev->caps.non_alpha_only_l1 = true;
+		if (ldev->caps.hw_version == HWVER_10200)
+			ldev->caps.pad_max_freq_hz = 65000000;
+		ldev->caps.nb_irq = 2;
+		ldev->caps.ycbcr_input = false;
+		ldev->caps.ycbcr_output = false;
+		ldev->caps.plane_reg_shadow = false;
+		ldev->caps.crc = false;
+		ldev->caps.dynamic_zorder = false;
+		ldev->caps.plane_rotation = false;
+		ldev->caps.fifo_threshold = false;
+		break;
+	case HWVER_20101:
+		ldev->caps.layer_ofs = LAY_OFS_0;
+		ldev->caps.layer_regs = ltdc_layer_regs_a1;
+		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
+		ldev->caps.pix_fmt_drm = ltdc_drm_fmt_a1;
+		ldev->caps.pix_fmt_nb = ARRAY_SIZE(ltdc_drm_fmt_a1);
+		ldev->caps.pix_fmt_flex = false;
+		ldev->caps.non_alpha_only_l1 = false;
+		ldev->caps.pad_max_freq_hz = 150000000;
+		ldev->caps.nb_irq = 4;
+		ldev->caps.ycbcr_input = false;
+		ldev->caps.ycbcr_output = false;
+		ldev->caps.plane_reg_shadow = false;
+		ldev->caps.crc = false;
+		ldev->caps.dynamic_zorder = false;
+		ldev->caps.plane_rotation = false;
+		ldev->caps.fifo_threshold = false;
+		break;
+	case HWVER_40100:
+	case HWVER_40101:
+		ldev->caps.layer_ofs = LAY_OFS_1;
+		ldev->caps.layer_regs = ltdc_layer_regs_a2;
+		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a2;
+		ldev->caps.pix_fmt_drm = ltdc_drm_fmt_a2;
+		ldev->caps.pix_fmt_nb = ARRAY_SIZE(ltdc_drm_fmt_a2);
+		ldev->caps.pix_fmt_flex = true;
+		ldev->caps.non_alpha_only_l1 = false;
+		ldev->caps.nb_irq = 2;
+		ldev->caps.ycbcr_input = true;
+		ldev->caps.ycbcr_output = true;
+		ldev->caps.plane_reg_shadow = true;
+		ldev->caps.crc = true;
+		ldev->caps.dynamic_zorder = true;
+		ldev->caps.plane_rotation = true;
+		ldev->caps.fifo_threshold = true;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+void ltdc_suspend(struct drm_device *ddev)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+
+	drm_dbg_driver(ddev, "\n");
+	clk_disable_unprepare(ldev->pixel_clk);
+	if (ldev->bus_clk)
+		clk_disable_unprepare(ldev->bus_clk);
+	if (ldev->lvds_clk)
+		clk_disable_unprepare(ldev->lvds_clk);
+}
+
+int ltdc_resume(struct drm_device *ddev)
+{
+	struct ltdc_device *ldev = ddev->dev_private;
+	int ret;
+
+	drm_dbg_driver(ddev, "\n");
+
+	ret = clk_prepare_enable(ldev->pixel_clk);
+	if (ret) {
+		drm_err(ddev, "failed to enable pixel clock (%d)\n", ret);
+		return ret;
+	}
+
+	if (ldev->bus_clk) {
+		ret = clk_prepare_enable(ldev->bus_clk);
+		if (ret) {
+			drm_err(ddev, "failed to enable bus clock (%d)\n", ret);
+			return ret;
+		}
+	}
+
+	if (ldev->lvds_clk) {
+		ret = clk_prepare_enable(ldev->lvds_clk);
+		if (ret)
+			drm_err(ddev, "failed to prepare lvds clock\n");
+	}
+
+	return ret;
+}
+
+int ltdc_load(struct drm_device *ddev)
+{
+	struct platform_device *pdev = to_platform_device(ddev->dev);
+	struct ltdc_device *ldev = ddev->dev_private;
+	struct device *dev = ddev->dev;
+	struct device_node *np = dev->of_node;
+	struct drm_bridge *bridge;
+	struct drm_panel *panel;
+	struct drm_crtc *crtc;
+	struct reset_control *rstc;
+	int irq, i, nb_endpoints;
+	int ret = -ENODEV;
+
+	drm_dbg_driver(ddev, "\n");
+
+	/* Get number of endpoints */
+	nb_endpoints = of_graph_get_endpoint_count(np);
+	if (!nb_endpoints)
+		return -ENODEV;
+
+	ldev->pixel_clk = devm_clk_get(dev, "lcd");
+	if (IS_ERR(ldev->pixel_clk)) {
+		if (PTR_ERR(ldev->pixel_clk) != -EPROBE_DEFER)
+			drm_err(ddev, "Unable to get lcd clock\n");
+		return PTR_ERR(ldev->pixel_clk);
+	}
+
+	if (clk_prepare_enable(ldev->pixel_clk)) {
+		drm_err(ddev, "Unable to prepare pixel clock\n");
+		return -ENODEV;
+	}
+
+	if (of_device_is_compatible(np, "st,stm32mp251-ltdc") ||
+	    of_device_is_compatible(np, "st,stm32mp255-ltdc")) {
+		ldev->bus_clk = devm_clk_get(dev, "bus");
+		if (IS_ERR(ldev->bus_clk))
+			return dev_err_probe(dev, PTR_ERR(ldev->bus_clk),
+					     "Unable to get bus clock\n");
+
+		ret = clk_prepare_enable(ldev->bus_clk);
+		if (ret) {
+			drm_err(ddev, "Unable to prepare bus clock\n");
+			return ret;
+		}
+	}
+
+	/* Get endpoints if any */
+	for (i = 0; i < nb_endpoints; i++) {
+		ret = drm_of_find_panel_or_bridge(np, 0, i, &panel, &bridge);
+
+		/*
+		 * If at least one endpoint is -ENODEV, continue probing,
+		 * else if at least one endpoint returned an error
+		 * (ie -EPROBE_DEFER) then stop probing.
+		 */
+		if (ret == -ENODEV)
+			continue;
+		else if (ret)
+			goto err;
+
+		if (panel) {
+			bridge = drmm_panel_bridge_add(ddev, panel);
+			drm_panel_put(panel);
+			if (IS_ERR(bridge)) {
+				drm_err(ddev, "panel-bridge endpoint %d\n", i);
+				ret = PTR_ERR(bridge);
+				goto err;
+			}
+		}
+
+		if (bridge) {
+			ret = ltdc_encoder_init(ddev, bridge);
+			if (ret) {
+				if (ret != -EPROBE_DEFER)
+					drm_err(ddev, "init encoder endpoint %d\n", i);
+				goto err;
+			}
+		}
+	}
+
+	ldev->lvds_clk = devm_clk_get(dev, "lvds");
+	if (IS_ERR(ldev->lvds_clk))
+		ldev->lvds_clk = NULL;
+
+	rstc = devm_reset_control_get_exclusive(dev, NULL);
+
+	mutex_init(&ldev->err_lock);
+
+	if (!IS_ERR(rstc)) {
+		reset_control_assert(rstc);
+		usleep_range(10, 20);
+		reset_control_deassert(rstc);
+	}
+
+	ldev->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ldev->regs)) {
+		drm_err(ddev, "Unable to get ltdc registers\n");
+		ret = PTR_ERR(ldev->regs);
+		goto err;
+	}
+
+	ldev->regmap = devm_regmap_init_mmio(&pdev->dev, ldev->regs, &stm32_ltdc_regmap_cfg);
+	if (IS_ERR(ldev->regmap)) {
+		drm_err(ddev, "Unable to regmap ltdc registers\n");
+		ret = PTR_ERR(ldev->regmap);
+		goto err;
+	}
+
+	ret = ltdc_get_caps(ddev);
+	if (ret) {
+		drm_err(ddev, "hardware identifier (0x%08x) not supported!\n",
+			ldev->caps.hw_version);
+		goto err;
+	}
+
+	/* Disable all interrupts */
+	regmap_clear_bits(ldev->regmap, LTDC_IER, IER_MASK);
+
+	drm_dbg_driver(ddev, "ltdc hw version 0x%08x\n", ldev->caps.hw_version);
+
+	/* initialize default value for fifo underrun threshold & clear interrupt error counters */
+	ldev->transfer_err = 0;
+	ldev->fifo_err = 0;
+	ldev->fifo_warn = 0;
+	ldev->fifo_threshold = FUT_DFT;
+
+	for (i = 0; i < ldev->caps.nb_irq; i++) {
+		irq = platform_get_irq(pdev, i);
+		if (irq < 0) {
+			ret = irq;
+			goto err;
+		}
+
+		ret = devm_request_threaded_irq(dev, irq, ltdc_irq,
+						ltdc_irq_thread, IRQF_ONESHOT,
+						dev_name(dev), ddev);
+		if (ret) {
+			drm_err(ddev, "Failed to register LTDC interrupt\n");
+			goto err;
+		}
+	}
+
+	crtc = drmm_kzalloc(ddev, sizeof(*crtc), GFP_KERNEL);
+	if (!crtc) {
+		drm_err(ddev, "Failed to allocate crtc\n");
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ret = ltdc_crtc_init(ddev, crtc);
+	if (ret) {
+		drm_err(ddev, "Failed to init crtc\n");
+		goto err;
+	}
+
+	ret = drm_vblank_init(ddev, NB_CRTC);
+	if (ret) {
+		drm_err(ddev, "Failed calling drm_vblank_init()\n");
+		goto err;
+	}
+
+	clk_disable_unprepare(ldev->pixel_clk);
+
+	if (ldev->bus_clk)
+		clk_disable_unprepare(ldev->bus_clk);
+
+	pinctrl_pm_select_sleep_state(ddev->dev);
+
+	pm_runtime_enable(ddev->dev);
+
+	return 0;
+err:
+	clk_disable_unprepare(ldev->pixel_clk);
+
+	if (ldev->bus_clk)
+		clk_disable_unprepare(ldev->bus_clk);
+
+	return ret;
+}
+
+void ltdc_unload(struct drm_device *ddev)
+{
+	drm_dbg_driver(ddev, "\n");
+
+	pm_runtime_disable(ddev->dev);
+}
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
+MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
new file mode 100644
index 000000000..452352e64
--- /dev/null
+++ b/drivers/gpu/drm/stm/ltdc.h
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Mickael Reulier <mickael.reulier@st.com>
+ */
+
+#ifndef _LTDC_H_
+#define _LTDC_H_
+
+struct ltdc_caps {
+	u32 hw_version;		/* hardware version */
+	u32 nb_layers;		/* number of supported layers */
+	u32 layer_ofs;		/* layer offset for applicable regs */
+	const u32 *layer_regs;	/* layer register offset */
+	u32 bus_width;		/* bus width (32 or 64 bits) */
+	const u32 *pix_fmt_hw;	/* supported hw pixel formats */
+	const u32 *pix_fmt_drm;	/* supported drm pixel formats */
+	int pix_fmt_nb;		/* number of pixel format */
+	bool pix_fmt_flex;	/* pixel format flexibility supported */
+	bool non_alpha_only_l1; /* non-native no-alpha formats on layer 1 */
+	int pad_max_freq_hz;	/* max frequency supported by pad */
+	int nb_irq;		/* number of hardware interrupts */
+	bool ycbcr_input;	/* ycbcr input converter supported */
+	bool ycbcr_output;	/* ycbcr output converter supported */
+	bool plane_reg_shadow;	/* plane shadow registers ability */
+	bool crc;		/* cyclic redundancy check supported */
+	bool dynamic_zorder;	/* dynamic z-order */
+	bool plane_rotation;	/* plane rotation */
+	bool fifo_threshold;	/* fifo underrun threshold supported */
+};
+
+#define LTDC_MAX_LAYER	4
+
+struct fps_info {
+	unsigned int counter;
+	ktime_t last_timestamp;
+};
+
+struct ltdc_plat_data {
+	int pad_max_freq_hz;	/* max frequency supported by pad */
+};
+
+struct ltdc_device {
+	void __iomem *regs;
+	struct regmap *regmap;
+	struct clk *pixel_clk;	/* lcd pixel clock */
+	struct clk *lvds_clk;	/* lvds pixel clock */
+	struct clk *bus_clk;	/* bus clock */
+	struct mutex err_lock;	/* protecting error_status */
+	struct ltdc_caps caps;
+	u32 irq_status;
+	u32 fifo_err;		/* fifo underrun error counter */
+	u32 fifo_warn;		/* fifo underrun warning counter */
+	u32 fifo_threshold;	/* fifo underrun threshold */
+	u32 transfer_err;	/* transfer error counter */
+	struct fps_info plane_fpsi[LTDC_MAX_LAYER];
+	struct drm_atomic_commit *suspend_state;
+	int crc_skip_count;
+	bool crc_active;
+};
+
+int ltdc_load(struct drm_device *ddev);
+void ltdc_unload(struct drm_device *ddev);
+void ltdc_suspend(struct drm_device *ddev);
+int ltdc_resume(struct drm_device *ddev);
+
+#endif
diff --git a/drivers/gpu/drm/stm/lvds.c b/drivers/gpu/drm/stm/lvds.c
new file mode 100644
index 000000000..1072dbe7b
--- /dev/null
+++ b/drivers/gpu/drm/stm/lvds.c
@@ -0,0 +1,1228 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023, STMicroelectronics - All Rights Reserved
+ * Author(s): Raphaël GALLAIS-POU <raphael.gallais-pou@foss.st.com> for STMicroelectronics.
+ */
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_device.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+#include <drm/drm_probe_helper.h>
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+/* LVDS Host registers */
+#define LVDS_CR		0x0000  /* configuration register */
+#define LVDS_DMLCR0	0x0004  /* data mapping lsb configuration register 0 */
+#define LVDS_DMMCR0	0x0008  /* data mapping msb configuration register 0 */
+#define LVDS_DMLCR1	0x000C  /* data mapping lsb configuration register 1 */
+#define LVDS_DMMCR1	0x0010  /* data mapping msb configuration register 1 */
+#define LVDS_DMLCR2	0x0014  /* data mapping lsb configuration register 2 */
+#define LVDS_DMMCR2	0x0018  /* data mapping msb configuration register 2 */
+#define LVDS_DMLCR3	0x001C  /* data mapping lsb configuration register 3 */
+#define LVDS_DMMCR3	0x0020  /* data mapping msb configuration register 3 */
+#define LVDS_DMLCR4	0x0024  /* data mapping lsb configuration register 4 */
+#define LVDS_DMMCR4	0x0028  /* data mapping msb configuration register 4 */
+#define LVDS_CDL1CR	0x002C  /* channel distrib link 1 configuration register */
+#define LVDS_CDL2CR	0x0030  /* channel distrib link 2 configuration register */
+
+#define CDL1CR_DEFAULT	0x04321 /* Default value for CDL1CR */
+#define CDL2CR_DEFAULT	0x59876 /* Default value for CDL2CR */
+
+#define LVDS_DMLCR(bit)	(LVDS_DMLCR0 + 0x8 * (bit))
+#define LVDS_DMMCR(bit)	(LVDS_DMMCR0 + 0x8 * (bit))
+
+/* LVDS Wrapper registers */
+#define LVDS_WCLKCR	0x11B0  /* Wrapper clock control register */
+
+#define LVDS_HWCFGR	0x1FF0  /* HW configuration register	*/
+#define LVDS_VERR	0x1FF4  /* Version register	*/
+#define LVDS_IPIDR	0x1FF8  /* Identification register	*/
+#define LVDS_SIDR	0x1FFC  /* Size Identification register	*/
+
+/* Bitfield description */
+#define CR_LVDSEN	BIT(0)  /* LVDS PHY Enable */
+#define CR_HSPOL	BIT(1)  /* Horizontal Synchronization Polarity */
+#define CR_VSPOL	BIT(2)  /* Vertical Synchronization Polarity */
+#define CR_DEPOL	BIT(3)  /* Data Enable Polarity */
+#define CR_CI		BIT(4)  /* Control Internal (software controlled bit) */
+#define CR_LKMOD	BIT(5)  /* Link Mode, for both Links */
+#define CR_LKPHA	BIT(6)  /* Link Phase, for both Links */
+#define CR_LK1POL	GENMASK(20, 16)  /* Link-1 output Polarity */
+#define CR_LK2POL	GENMASK(25, 21)  /* Link-2 output Polarity */
+
+#define DMMCR_MAP0	GENMASK(4, 0) /* Mapping for bit 0 of datalane x */
+#define DMMCR_MAP1	GENMASK(9, 5) /* Mapping for bit 1 of datalane x */
+#define DMMCR_MAP2	GENMASK(14, 10) /* Mapping for bit 2 of datalane x */
+#define DMMCR_MAP3	GENMASK(19, 15) /* Mapping for bit 3 of datalane x */
+#define DMLCR_MAP4	GENMASK(4, 0) /* Mapping for bit 4 of datalane x */
+#define DMLCR_MAP5	GENMASK(9, 5) /* Mapping for bit 5 of datalane x */
+#define DMLCR_MAP6	GENMASK(14, 10) /* Mapping for bit 6 of datalane x */
+
+#define CDLCR_DISTR0	GENMASK(3, 0) /* Channel distribution for lane 0 */
+#define CDLCR_DISTR1	GENMASK(7, 4) /* Channel distribution for lane 1 */
+#define CDLCR_DISTR2	GENMASK(11, 8) /* Channel distribution for lane 2 */
+#define CDLCR_DISTR3	GENMASK(15, 12) /* Channel distribution for lane 3 */
+#define CDLCR_DISTR4	GENMASK(19, 16) /* Channel distribution for lane 4 */
+
+#define PHY_GCR_BIT_CLK_OUT	BIT(0)  /* BIT clock enable */
+#define PHY_GCR_LS_CLK_OUT	BIT(4)  /* LS clock enable */
+#define PHY_GCR_DP_CLK_OUT	BIT(8)  /* DP clock enable */
+#define PHY_GCR_RSTZ		BIT(24) /* LVDS PHY digital reset */
+#define PHY_GCR_DIV_RSTN	BIT(25) /* Output divider reset */
+#define PHY_SCR_TX_EN		BIT(16) /* Transmission mode enable */
+/* Current mode driver enable */
+#define PHY_CMCR_CM_EN_DL	(BIT(28) | BIT(20) | BIT(12) | BIT(4))
+#define PHY_CMCR_CM_EN_DL4	BIT(4)
+/* Bias enable */
+#define PHY_BCR1_EN_BIAS_DL	(BIT(16) | BIT(12) | BIT(8) | BIT(4) | BIT(0))
+#define PHY_BCR2_BIAS_EN	BIT(28)
+/* Voltage mode driver enable */
+#define PHY_BCR3_VM_EN_DL	(BIT(16) | BIT(12) | BIT(8) | BIT(4) | BIT(0))
+#define PHY_DCR_POWER_OK	BIT(12)
+#define PHY_CFGCR_EN_DIG_DL	GENMASK(4, 0) /* LVDS PHY digital lane enable */
+#define PHY_PLLCR1_PLL_EN	BIT(0) /* LVDS PHY PLL enable */
+#define PHY_PLLCR1_EN_SD	BIT(1) /* LVDS PHY PLL sigma-delta signal enable */
+#define PHY_PLLCR1_EN_TWG	BIT(2) /* LVDS PHY PLL triangular wave generator enable */
+#define PHY_PLLCR1_DIV_EN	BIT(8) /* LVDS PHY PLL dividers enable */
+#define PHY_PLLCR2_NDIV		GENMASK(25, 16) /* NDIV mask value */
+#define PHY_PLLCR2_BDIV		GENMASK(9, 0)   /* BDIV mask value */
+#define PHY_PLLSR_PLL_LOCK	BIT(0) /* LVDS PHY PLL lock status */
+#define PHY_PLLSDCR1_MDIV	GENMASK(9, 0)   /* MDIV mask value */
+#define PHY_PLLTESTCR_TDIV	GENMASK(25, 16) /* TDIV mask value */
+#define PHY_PLLTESTCR_CLK_EN	BIT(0) /* Test clock enable */
+#define PHY_PLLTESTCR_EN	BIT(8) /* Test divider output enable */
+
+#define WCLKCR_SECND_CLKPIX_SEL	BIT(0) /* Pixel clock selection */
+#define WCLKCR_SRCSEL		BIT(8) /* Source selection for the pixel clock */
+
+/* Sleep & timeout for pll lock/unlock */
+#define SLEEP_US	1000
+#define TIMEOUT_US	200000
+
+/*
+ * The link phase defines whether an ODD pixel is carried over together with
+ * the next EVEN pixel or together with the previous EVEN pixel.
+ *
+ * LVDS_DUAL_LINK_EVEN_ODD_PIXELS (LKPHA = 0)
+ *
+ * ,--------.  ,--------.  ,--------.  ,--------.  ,---------.
+ * | ODD  LK \/ PIXEL  3 \/ PIXEL  1 \/ PIXEL' 1 \/ PIXEL' 3 |
+ * | EVEN LK /\ PIXEL  2 /\ PIXEL' 0 /\ PIXEL' 2 /\ PIXEL' 4 |
+ * `--------'  `--------'  `--------'  `--------'  `---------'
+ *
+ * LVDS_DUAL_LINK_ODD_EVEN_PIXELS (LKPHA = 1)
+ *
+ * ,--------.  ,--------.  ,--------.  ,--------.  ,---------.
+ * | ODD  LK \/ PIXEL  3 \/ PIXEL  1 \/ PIXEL' 1 \/ PIXEL' 3 |
+ * | EVEN LK /\ PIXEL  4 /\ PIXEL  2 /\ PIXEL' 0 /\ PIXEL' 2 |
+ * `--------'  `--------'  `--------'  `--------'  `---------'
+ *
+ */
+enum lvds_link_type {
+	LVDS_SINGLE_LINK_PRIMARY = 0,
+	LVDS_SINGLE_LINK_SECONDARY,
+	LVDS_DUAL_LINK_EVEN_ODD_PIXELS,
+	LVDS_DUAL_LINK_ODD_EVEN_PIXELS,
+};
+
+enum lvds_pixel {
+	PIX_R_0 = 0,
+	PIX_R_1,
+	PIX_R_2,
+	PIX_R_3,
+	PIX_R_4,
+	PIX_R_5,
+	PIX_R_6,
+	PIX_R_7,
+	PIX_G_0,
+	PIX_G_1,
+	PIX_G_2,
+	PIX_G_3,
+	PIX_G_4,
+	PIX_G_5,
+	PIX_G_6,
+	PIX_G_7,
+	PIX_B_0,
+	PIX_B_1,
+	PIX_B_2,
+	PIX_B_3,
+	PIX_B_4,
+	PIX_B_5,
+	PIX_B_6,
+	PIX_B_7,
+	PIX_H_S,
+	PIX_V_S,
+	PIX_D_E,
+	PIX_C_E,
+	PIX_C_I,
+	PIX_TOG,
+	PIX_ONE,
+	PIX_ZER,
+};
+
+struct phy_reg_offsets {
+	u32 GCR;	/* Global Control Register	*/
+	u32 CMCR1;    /* Current Mode Control Register 1 */
+	u32 CMCR2;    /* Current Mode Control Register 2 */
+	u32 SCR;      /* Serial Control Register	*/
+	u32 BCR1;     /* Bias Control Register 1	*/
+	u32 BCR2;     /* Bias Control Register 2	*/
+	u32 BCR3;     /* Bias Control Register 3	*/
+	u32 MPLCR;    /* Monitor PLL Lock Control Register */
+	u32 DCR;      /* Debug Control Register	*/
+	u32 SSR1;     /* Spare Status Register 1	*/
+	u32 CFGCR;    /* Configuration Control Register */
+	u32 PLLCR1;   /* PLL_MODE 1 Control Register	*/
+	u32 PLLCR2;   /* PLL_MODE 2 Control Register	*/
+	u32 PLLSR;    /* PLL Status Register	*/
+	u32 PLLSDCR1; /* PLL_SD_1 Control Register	*/
+	u32 PLLSDCR2; /* PLL_SD_2 Control Register	*/
+	u32 PLLTWGCR1;/* PLL_TWG_1 Control Register	*/
+	u32 PLLTWGCR2;/* PLL_TWG_2 Control Register	*/
+	u32 PLLCPCR;  /* PLL_CP Control Register	*/
+	u32 PLLTESTCR;/* PLL_TEST Control Register	*/
+};
+
+struct lvds_phy_info {
+	u32 base;
+	struct phy_reg_offsets ofs;
+};
+
+static struct lvds_phy_info lvds_phy_16ff_primary = {
+	.base = 0x1000,
+	.ofs = {
+		.GCR = 0x0,
+		.CMCR1 = 0xC,
+		.CMCR2 = 0x10,
+		.SCR = 0x20,
+		.BCR1 = 0x2C,
+		.BCR2 = 0x30,
+		.BCR3 = 0x34,
+		.MPLCR = 0x64,
+		.DCR = 0x84,
+		.SSR1 = 0x88,
+		.CFGCR = 0xA0,
+		.PLLCR1 = 0xC0,
+		.PLLCR2 = 0xC4,
+		.PLLSR = 0xC8,
+		.PLLSDCR1 = 0xCC,
+		.PLLSDCR2 = 0xD0,
+		.PLLTWGCR1 = 0xD4,
+		.PLLTWGCR2 = 0xD8,
+		.PLLCPCR = 0xE0,
+		.PLLTESTCR = 0xE8,
+	}
+};
+
+static struct lvds_phy_info lvds_phy_16ff_secondary = {
+	.base = 0x1100,
+	.ofs = {
+		.GCR = 0x0,
+		.CMCR1 = 0xC,
+		.CMCR2 = 0x10,
+		.SCR = 0x20,
+		.BCR1 = 0x2C,
+		.BCR2 = 0x30,
+		.BCR3 = 0x34,
+		.MPLCR = 0x64,
+		.DCR = 0x84,
+		.SSR1 = 0x88,
+		.CFGCR = 0xA0,
+		.PLLCR1 = 0xC0,
+		.PLLCR2 = 0xC4,
+		.PLLSR = 0xC8,
+		.PLLSDCR1 = 0xCC,
+		.PLLSDCR2 = 0xD0,
+		.PLLTWGCR1 = 0xD4,
+		.PLLTWGCR2 = 0xD8,
+		.PLLCPCR = 0xE0,
+		.PLLTESTCR = 0xE8,
+	}
+};
+
+struct stm_lvds {
+	void __iomem *base;
+	struct device *dev;
+	struct clk *pclk;		/* APB peripheral clock */
+	struct clk *pllref_clk;		/* Reference clock for the internal PLL */
+	struct clk_hw lvds_ck_px;	/* Pixel clock */
+	u32 pixel_clock_rate;		/* Pixel clock rate */
+
+	struct lvds_phy_info *primary;
+	struct lvds_phy_info *secondary;
+
+	struct drm_bridge lvds_bridge;
+	struct drm_bridge *next_bridge;
+	struct drm_connector connector;
+	struct drm_encoder *encoder;
+	struct drm_panel *panel;
+
+	u32 hw_version;
+	u32 link_type;
+};
+
+#define bridge_to_stm_lvds(b) \
+	container_of(b, struct stm_lvds, lvds_bridge)
+
+#define connector_to_stm_lvds(c) \
+	container_of(c, struct stm_lvds, connector)
+
+#define lvds_is_dual_link(lvds) \
+	({	\
+	typeof(lvds) __lvds = (lvds);	\
+	__lvds == LVDS_DUAL_LINK_EVEN_ODD_PIXELS ||	\
+	__lvds == LVDS_DUAL_LINK_ODD_EVEN_PIXELS;	\
+	})
+
+static inline void lvds_write(struct stm_lvds *lvds, u32 reg, u32 val)
+{
+	writel(val, lvds->base + reg);
+}
+
+static inline u32 lvds_read(struct stm_lvds *lvds, u32 reg)
+{
+	return readl(lvds->base + reg);
+}
+
+static inline void lvds_set(struct stm_lvds *lvds, u32 reg, u32 mask)
+{
+	lvds_write(lvds, reg, lvds_read(lvds, reg) | mask);
+}
+
+static inline void lvds_clear(struct stm_lvds *lvds, u32 reg, u32 mask)
+{
+	lvds_write(lvds, reg, lvds_read(lvds, reg) & ~mask);
+}
+
+/*
+ * Expected JEIDA-RGB888 data to be sent in LSB format
+ *	    bit6 ............................bit0
+ * CHAN0   {ONE, ONE, ZERO, ZERO, ZERO, ONE, ONE}
+ * CHAN1   {G2,  R7,  R6,   R5,   R4,   R3,  R2}
+ * CHAN2   {B3,  B2,  G7,   G6,   G5,   G4,  G3}
+ * CHAN3   {DE,  VS,  HS,   B7,   B6,   B5,  B4}
+ * CHAN4   {CE,  B1,  B0,   G1,   G0,   R1,  R0}
+ */
+static enum lvds_pixel lvds_bitmap_jeida_rgb888[5][7] = {
+	{ PIX_ONE, PIX_ONE, PIX_ZER, PIX_ZER, PIX_ZER, PIX_ONE, PIX_ONE },
+	{ PIX_G_2, PIX_R_7, PIX_R_6, PIX_R_5, PIX_R_4, PIX_R_3, PIX_R_2 },
+	{ PIX_B_3, PIX_B_2, PIX_G_7, PIX_G_6, PIX_G_5, PIX_G_4, PIX_G_3 },
+	{ PIX_D_E, PIX_V_S, PIX_H_S, PIX_B_7, PIX_B_6, PIX_B_5, PIX_B_4 },
+	{ PIX_C_E, PIX_B_1, PIX_B_0, PIX_G_1, PIX_G_0, PIX_R_1, PIX_R_0 }
+};
+
+/*
+ * Expected VESA-RGB888 data to be sent in LSB format
+ *	    bit6 ............................bit0
+ * CHAN0   {ONE, ONE, ZERO, ZERO, ZERO, ONE, ONE}
+ * CHAN1   {G0,  R5,  R4,   R3,   R2,   R1,  R0}
+ * CHAN2   {B1,  B0,  G5,   G4,   G3,   G2,  G1}
+ * CHAN3   {DE,  VS,  HS,   B5,   B4,   B3,  B2}
+ * CHAN4   {CE,  B7,  B6,   G7,   G6,   R7,  R6}
+ */
+static enum lvds_pixel lvds_bitmap_vesa_rgb888[5][7] = {
+	{ PIX_ONE, PIX_ONE, PIX_ZER, PIX_ZER, PIX_ZER, PIX_ONE, PIX_ONE },
+	{ PIX_G_0, PIX_R_5, PIX_R_4, PIX_R_3, PIX_R_2, PIX_R_1, PIX_R_0 },
+	{ PIX_B_1, PIX_B_0, PIX_G_5, PIX_G_4, PIX_G_3, PIX_G_2, PIX_G_1 },
+	{ PIX_D_E, PIX_V_S, PIX_H_S, PIX_B_5, PIX_B_4, PIX_B_3, PIX_B_2 },
+	{ PIX_C_E, PIX_B_7, PIX_B_6, PIX_G_7, PIX_G_6, PIX_R_7, PIX_R_6 }
+};
+
+/*
+ * Clocks and PHY related functions
+ */
+static int lvds_pll_enable(struct stm_lvds *lvds, struct lvds_phy_info *phy)
+{
+	struct drm_device *drm = lvds->lvds_bridge.dev;
+	u32 lvds_gcr;
+	int val, ret;
+
+	/*
+	 * PLL lock timing control for the monitor unmask after startup (pll_en)
+	 * Adjusted value so that the masking window is opened at start-up
+	 */
+	lvds_write(lvds, phy->base + phy->ofs.MPLCR, (0x200 - 0x160) << 16);
+
+	/* Enable bias */
+	lvds_write(lvds, phy->base + phy->ofs.BCR2, PHY_BCR2_BIAS_EN);
+
+	/* Enable DP, LS, BIT clock output */
+	lvds_gcr = PHY_GCR_DP_CLK_OUT | PHY_GCR_LS_CLK_OUT | PHY_GCR_BIT_CLK_OUT;
+	lvds_set(lvds, phy->base + phy->ofs.GCR, lvds_gcr);
+
+	/* Power up all output dividers */
+	lvds_set(lvds, phy->base + phy->ofs.PLLTESTCR, PHY_PLLTESTCR_EN);
+	lvds_set(lvds, phy->base + phy->ofs.PLLCR1, PHY_PLLCR1_DIV_EN);
+
+	/* Set PHY in serial transmission mode */
+	lvds_set(lvds, phy->base + phy->ofs.SCR, PHY_SCR_TX_EN);
+
+	/* Enable the LVDS PLL & wait for its lock */
+	lvds_set(lvds, phy->base + phy->ofs.PLLCR1, PHY_PLLCR1_PLL_EN);
+	ret = readl_poll_timeout_atomic(lvds->base + phy->base + phy->ofs.PLLSR,
+					val, val & PHY_PLLSR_PLL_LOCK,
+					SLEEP_US, TIMEOUT_US);
+	if (ret)
+		drm_err(drm, "!TIMEOUT! waiting PLL, let's continue\n");
+
+	/* WCLKCR_SECND_CLKPIX_SEL is for dual link */
+	lvds_write(lvds, LVDS_WCLKCR, WCLKCR_SECND_CLKPIX_SEL);
+
+	lvds_set(lvds, phy->ofs.PLLTESTCR, PHY_PLLTESTCR_CLK_EN);
+
+	return ret;
+}
+
+static int pll_get_clkout_khz(int clkin_khz, int bdiv, int mdiv, int ndiv)
+{
+	int divisor = ndiv * bdiv;
+
+	/* Prevents from division by 0 */
+	if (!divisor)
+		return 0;
+
+	return clkin_khz * mdiv / divisor;
+}
+
+#define TDIV	70
+#define NDIV_MIN	2
+#define NDIV_MAX	6
+#define BDIV_MIN	2
+#define BDIV_MAX	6
+#define MDIV_MIN	1
+#define MDIV_MAX	1023
+
+static int lvds_pll_get_params(struct stm_lvds *lvds,
+			       unsigned int clkin_khz, unsigned int clkout_khz,
+			       unsigned int *bdiv, unsigned int *mdiv, unsigned int *ndiv)
+{
+	int delta, best_delta; /* all in khz */
+	int i, o, n;
+
+	/* Early checks preventing division by 0 & odd results */
+	if (clkin_khz <= 0 || clkout_khz <= 0)
+		return -EINVAL;
+
+	best_delta = 1000000; /* big started value (1000000khz) */
+
+	for (i = NDIV_MIN; i <= NDIV_MAX; i++) {
+		for (o = BDIV_MIN; o <= BDIV_MAX; o++) {
+			n = DIV_ROUND_CLOSEST(i * o * clkout_khz, clkin_khz);
+			/* Check ndiv according to vco range */
+			if (n < MDIV_MIN || n > MDIV_MAX)
+				continue;
+			/* Check if new delta is better & saves parameters */
+			delta = pll_get_clkout_khz(clkin_khz, i, n, o) - clkout_khz;
+			if (delta < 0)
+				delta = -delta;
+			if (delta < best_delta) {
+				*ndiv = i;
+				*mdiv = n;
+				*bdiv = o;
+				best_delta = delta;
+			}
+			/* fast return in case of "perfect result" */
+			if (!delta)
+				return 0;
+		}
+	}
+
+	return 0;
+}
+
+static void lvds_pll_config(struct stm_lvds *lvds, struct lvds_phy_info *phy)
+{
+	unsigned int pll_in_khz, bdiv = 0, mdiv = 0, ndiv = 0;
+	struct clk_hw *hwclk;
+	int multiplier;
+
+	/*
+	 * The LVDS PHY includes a low power low jitter high performance and
+	 * highly configuration Phase Locked Loop supporting integer and
+	 * fractional multiplication ratios and Spread Spectrum Clocking.  In
+	 * integer mode, the only software supported feature for now, the PLL is
+	 * made of a pre-divider NDIV, a feedback multiplier MDIV, followed by
+	 * several post-dividers, each one with a specific application.
+	 *
+	 *          ,------.         ,-----.     ,-----.
+	 * Fref --> | NDIV | -Fpdf-> | PFD | --> | VCO | --------> Fvco
+	 *          `------'     ,-> |     |     `-----'  |
+	 *                       |   `-----'              |
+	 *                       |         ,------.       |
+	 *                       `-------- | MDIV | <-----'
+	 *                                 `------'
+	 *
+	 * From the output of the VCO, the clock can be optionally extracted on
+	 * the RCC clock observer, with a divider TDIV, for testing purpose, or
+	 * is passed through a programmable post-divider BDIV.  Finally, the
+	 * frequency can be divided further with two fixed dividers.
+	 *
+	 *                            ,--------.
+	 *                    ,-----> | DP div | ----------------> Fdp
+	 *          ,------.  |       `--------'
+	 * Fvco --> | BDIV | ------------------------------------> Fbit
+	 *      |   `------'    ,------.   |
+	 *      `-------------> | TDIV | --.---------------------> ClkObs
+	 *                      '------'   |    ,--------.
+	 *                                 `--> | LS div | ------> Fls
+	 *                                      '--------'
+	 *
+	 * The LS and DP clock dividers operate at a fixed ratio of 7 and 3.5
+	 * respectively with regards to fbit. LS divider converts the bit clock
+	 * to a pixel clock per lane per clock sample (Fls).  This is useful
+	 * when used to generate a dot clock for the display unit RGB output,
+	 * and DP divider is.
+	 */
+
+	hwclk = __clk_get_hw(lvds->pllref_clk);
+	if (!hwclk)
+		return;
+
+	pll_in_khz = clk_hw_get_rate(hwclk) / 1000;
+
+	if (lvds_is_dual_link(lvds->link_type))
+		multiplier = 2;
+	else
+		multiplier = 1;
+
+	lvds_pll_get_params(lvds, pll_in_khz,
+			    lvds->pixel_clock_rate * 7 / 1000 / multiplier,
+			    &bdiv, &mdiv, &ndiv);
+
+	/* Set BDIV, MDIV and NDIV */
+	lvds_write(lvds, phy->base + phy->ofs.PLLCR2, ndiv << 16);
+	lvds_set(lvds, phy->base + phy->ofs.PLLCR2, bdiv);
+	lvds_write(lvds, phy->base + phy->ofs.PLLSDCR1, mdiv);
+
+	/* Hardcode TDIV as dynamic values are not yet implemented */
+	lvds_write(lvds, phy->base + phy->ofs.PLLTESTCR, TDIV << 16);
+
+	/*
+	 * For now, PLL just needs to be in integer mode
+	 * Fractional and spread spectrum clocking are not yet implemented
+	 *
+	 * PLL integer mode:
+	 *	- PMRY_PLL_TWG_STEP = PMRY_PLL_SD_INT_RATIO
+	 *	- EN_TWG = 0
+	 *	- EN_SD = 0
+	 *	- DOWN_SPREAD = 0
+	 *
+	 * PLL fractional mode:
+	 *	- EN_TWG = 0
+	 *	- EN_SD = 1
+	 *	- DOWN_SPREAD = 0
+	 *
+	 * Spread Spectrum Clocking
+	 *	- EN_TWG = 1
+	 *	- EN_SD = 1
+	 */
+
+	/* Disable TWG and SD */
+	lvds_clear(lvds, phy->base + phy->ofs.PLLCR1, PHY_PLLCR1_EN_TWG | PHY_PLLCR1_EN_SD);
+
+	/* Power up bias and PLL dividers */
+	lvds_set(lvds, phy->base + phy->ofs.DCR, PHY_DCR_POWER_OK);
+	lvds_set(lvds, phy->base + phy->ofs.CMCR1, PHY_CMCR_CM_EN_DL);
+	lvds_set(lvds, phy->base + phy->ofs.CMCR2, PHY_CMCR_CM_EN_DL4);
+
+	/* Set up voltage mode */
+	lvds_set(lvds, phy->base + phy->ofs.PLLCPCR, 0x1);
+	lvds_set(lvds, phy->base + phy->ofs.BCR3, PHY_BCR3_VM_EN_DL);
+	lvds_set(lvds, phy->base + phy->ofs.BCR1, PHY_BCR1_EN_BIAS_DL);
+	/* Enable digital datalanes */
+	lvds_set(lvds, phy->base + phy->ofs.CFGCR, PHY_CFGCR_EN_DIG_DL);
+}
+
+static int lvds_pixel_clk_enable(struct clk_hw *hw)
+{
+	struct stm_lvds *lvds = container_of(hw, struct stm_lvds, lvds_ck_px);
+	struct drm_device *drm = lvds->lvds_bridge.dev;
+	struct lvds_phy_info *phy;
+	int ret;
+
+	ret = clk_prepare_enable(lvds->pclk);
+	if (ret) {
+		drm_err(drm, "Failed to enable lvds peripheral clk\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(lvds->pllref_clk);
+	if (ret) {
+		drm_err(drm, "Failed to enable lvds reference clk\n");
+		clk_disable_unprepare(lvds->pclk);
+		return ret;
+	}
+
+	/* In case we are operating in dual link the second PHY is set before the primary PHY. */
+	if (lvds->secondary) {
+		phy = lvds->secondary;
+
+		/* Release LVDS PHY from reset mode */
+		lvds_set(lvds, phy->base + phy->ofs.GCR, PHY_GCR_DIV_RSTN | PHY_GCR_RSTZ);
+		lvds_pll_config(lvds, phy);
+
+		ret = lvds_pll_enable(lvds, phy);
+		if (ret) {
+			drm_err(drm, "Failed to enable secondary PHY PLL: %d\n", ret);
+			return ret;
+		}
+	}
+
+	if (lvds->primary) {
+		phy = lvds->primary;
+
+		/* Release LVDS PHY from reset mode */
+		lvds_set(lvds, phy->base + phy->ofs.GCR, PHY_GCR_DIV_RSTN | PHY_GCR_RSTZ);
+		lvds_pll_config(lvds, phy);
+
+		ret = lvds_pll_enable(lvds, phy);
+		if (ret) {
+			drm_err(drm, "Failed to enable primary PHY PLL: %d\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void lvds_pixel_clk_disable(struct clk_hw *hw)
+{
+	struct stm_lvds *lvds = container_of(hw, struct stm_lvds, lvds_ck_px);
+
+	/*
+	 * For each PHY:
+	 * Disable DP, LS, BIT clock outputs
+	 * Shutdown the PLL
+	 * Assert LVDS PHY in reset mode
+	 */
+
+	if (lvds->primary) {
+		lvds_clear(lvds, lvds->primary->base + lvds->primary->ofs.GCR,
+			   (PHY_GCR_DP_CLK_OUT | PHY_GCR_LS_CLK_OUT | PHY_GCR_BIT_CLK_OUT));
+		lvds_clear(lvds, lvds->primary->base + lvds->primary->ofs.PLLCR1,
+			   PHY_PLLCR1_PLL_EN);
+		lvds_clear(lvds, lvds->primary->base + lvds->primary->ofs.GCR,
+			   PHY_GCR_DIV_RSTN | PHY_GCR_RSTZ);
+	}
+
+	if (lvds->secondary) {
+		lvds_clear(lvds, lvds->secondary->base + lvds->secondary->ofs.GCR,
+			   (PHY_GCR_DP_CLK_OUT | PHY_GCR_LS_CLK_OUT | PHY_GCR_BIT_CLK_OUT));
+		lvds_clear(lvds, lvds->secondary->base + lvds->secondary->ofs.PLLCR1,
+			   PHY_PLLCR1_PLL_EN);
+		lvds_clear(lvds, lvds->secondary->base + lvds->secondary->ofs.GCR,
+			   PHY_GCR_DIV_RSTN | PHY_GCR_RSTZ);
+	}
+
+	clk_disable_unprepare(lvds->pllref_clk);
+	clk_disable_unprepare(lvds->pclk);
+}
+
+static unsigned long lvds_pixel_clk_recalc_rate(struct clk_hw *hw,
+						unsigned long parent_rate)
+{
+	struct stm_lvds *lvds = container_of(hw, struct stm_lvds, lvds_ck_px);
+	struct drm_device *drm = lvds->lvds_bridge.dev;
+	unsigned int pll_in_khz, bdiv, mdiv, ndiv;
+	int ret, multiplier, pll_out_khz;
+	u32 val;
+
+	ret = clk_prepare_enable(lvds->pclk);
+	if (ret) {
+		drm_err(drm, "Failed to enable lvds peripheral clk\n");
+		return 0;
+	}
+
+	if (lvds_is_dual_link(lvds->link_type))
+		multiplier = 2;
+	else
+		multiplier = 1;
+
+	val = lvds_read(lvds, lvds->primary->base + lvds->primary->ofs.PLLCR2);
+
+	ndiv = (val & PHY_PLLCR2_NDIV) >> 16;
+	bdiv = (val & PHY_PLLCR2_BDIV) >> 0;
+
+	mdiv = (unsigned int)lvds_read(lvds,
+				       lvds->primary->base + lvds->primary->ofs.PLLSDCR1);
+
+	pll_in_khz = (unsigned int)(parent_rate / 1000);
+
+	/* Compute values if not yet accessible */
+	if (val == 0 || mdiv == 0) {
+		lvds_pll_get_params(lvds, pll_in_khz,
+				    lvds->pixel_clock_rate * 7 / 1000 / multiplier,
+				    &bdiv, &mdiv, &ndiv);
+	}
+
+	pll_out_khz = pll_get_clkout_khz(pll_in_khz, bdiv, mdiv, ndiv);
+	drm_dbg(drm, "ndiv %d , bdiv %d, mdiv %d, pll_out_khz %d\n",
+		ndiv, bdiv, mdiv, pll_out_khz);
+
+	/*
+	 * 1/7 because for each pixel in 1 lane there is 7 bits
+	 * We want pixclk, not bitclk
+	 */
+	lvds->pixel_clock_rate = pll_out_khz * 1000 * multiplier / 7;
+
+	clk_disable_unprepare(lvds->pclk);
+
+	return (unsigned long)lvds->pixel_clock_rate;
+}
+
+static int lvds_pixel_clk_determine_rate(struct clk_hw *hw,
+					 struct clk_rate_request *req)
+{
+	struct stm_lvds *lvds = container_of(hw, struct stm_lvds, lvds_ck_px);
+	unsigned int pll_in_khz, bdiv = 0, mdiv = 0, ndiv = 0;
+	const struct drm_connector *connector;
+	const struct drm_display_mode *mode;
+	int multiplier;
+
+	connector = &lvds->connector;
+	if (!connector)
+		return -EINVAL;
+
+	if (list_empty(&connector->modes)) {
+		drm_dbg(connector->dev, "connector: empty modes list\n");
+		return -EINVAL;
+	}
+
+	mode = list_first_entry(&connector->modes,
+				struct drm_display_mode, head);
+
+	pll_in_khz = (unsigned int)(req->best_parent_rate / 1000);
+
+	if (lvds_is_dual_link(lvds->link_type))
+		multiplier = 2;
+	else
+		multiplier = 1;
+
+	lvds_pll_get_params(lvds, pll_in_khz, mode->clock * 7 / multiplier, &bdiv, &mdiv, &ndiv);
+
+	/*
+	 * 1/7 because for each pixel in 1 lane there is 7 bits
+	 * We want pixclk, not bitclk
+	 */
+	lvds->pixel_clock_rate = (unsigned long)pll_get_clkout_khz(pll_in_khz, bdiv, mdiv, ndiv)
+					 * 1000 * multiplier / 7;
+
+	req->rate = lvds->pixel_clock_rate;
+
+	return 0;
+}
+
+static const struct clk_ops lvds_pixel_clk_ops = {
+	.enable = lvds_pixel_clk_enable,
+	.disable = lvds_pixel_clk_disable,
+	.recalc_rate = lvds_pixel_clk_recalc_rate,
+	.determine_rate = lvds_pixel_clk_determine_rate,
+};
+
+static const struct clk_init_data clk_data = {
+	.name = "clk_pix_lvds",
+	.ops = &lvds_pixel_clk_ops,
+	.parent_names = (const char * []) {"ck_ker_lvdsphy"},
+	.num_parents = 1,
+	.flags = CLK_IGNORE_UNUSED,
+};
+
+static void lvds_pixel_clk_unregister(void *data)
+{
+	struct stm_lvds *lvds = data;
+
+	of_clk_del_provider(lvds->dev->of_node);
+	clk_hw_unregister(&lvds->lvds_ck_px);
+}
+
+static int lvds_pixel_clk_register(struct stm_lvds *lvds)
+{
+	struct device_node *node = lvds->dev->of_node;
+	int ret;
+
+	lvds->lvds_ck_px.init = &clk_data;
+
+	/* set the rate by default at 148500000 */
+	lvds->pixel_clock_rate = 148500000;
+
+	ret = clk_hw_register(lvds->dev, &lvds->lvds_ck_px);
+	if (ret)
+		return ret;
+
+	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get,
+				     &lvds->lvds_ck_px);
+	if (ret)
+		clk_hw_unregister(&lvds->lvds_ck_px);
+
+	return ret;
+}
+
+/*
+ * Host configuration related
+ */
+static void lvds_config_data_mapping(struct stm_lvds *lvds)
+{
+	struct drm_device *drm = lvds->lvds_bridge.dev;
+	const struct drm_display_info *info;
+	enum lvds_pixel (*bitmap)[7];
+	u32 lvds_dmlcr, lvds_dmmcr;
+	int i;
+
+	info = &(&lvds->connector)->display_info;
+	if (!info->num_bus_formats || !info->bus_formats) {
+		drm_warn(drm, "No LVDS bus format reported\n");
+		return;
+	}
+
+	switch (info->bus_formats[0]) {
+	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG: /* VESA-RGB666 */
+		drm_warn(drm, "Pixel format with data mapping not yet supported.\n");
+		return;
+	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG: /* VESA-RGB888 */
+		bitmap = lvds_bitmap_vesa_rgb888;
+		break;
+	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA: /* JEIDA-RGB888 */
+		bitmap = lvds_bitmap_jeida_rgb888;
+		break;
+	default:
+		drm_warn(drm, "Unsupported LVDS bus format 0x%04x\n", info->bus_formats[0]);
+		return;
+	}
+
+	/* Set bitmap for each lane */
+	for (i = 0; i < 5; i++) {
+		lvds_dmlcr = ((bitmap[i][0])
+			      + (bitmap[i][1] << 5)
+			      + (bitmap[i][2] << 10)
+			      + (bitmap[i][3] << 15));
+		lvds_dmmcr = ((bitmap[i][4])
+			      + (bitmap[i][5] << 5)
+			      + (bitmap[i][6] << 10));
+
+		lvds_write(lvds, LVDS_DMLCR(i), lvds_dmlcr);
+		lvds_write(lvds, LVDS_DMMCR(i), lvds_dmmcr);
+	}
+}
+
+static void lvds_config_mode(struct stm_lvds *lvds)
+{
+	u32 bus_flags, lvds_cr = 0, lvds_cdl1cr = 0, lvds_cdl2cr = 0;
+	const struct drm_display_mode *mode;
+	const struct drm_connector *connector;
+
+	connector = &lvds->connector;
+	if (!connector)
+		return;
+
+	if (list_empty(&connector->modes)) {
+		drm_dbg(connector->dev, "connector: empty modes list\n");
+		return;
+	}
+
+	bus_flags = connector->display_info.bus_flags;
+	mode = list_first_entry(&connector->modes,
+				struct drm_display_mode, head);
+
+	lvds_clear(lvds, LVDS_CR, CR_LKMOD);
+	lvds_clear(lvds, LVDS_CDL1CR, CDLCR_DISTR0 | CDLCR_DISTR1 | CDLCR_DISTR2 |
+				      CDLCR_DISTR3 | CDLCR_DISTR4);
+	lvds_clear(lvds, LVDS_CDL2CR, CDLCR_DISTR0 | CDLCR_DISTR1 | CDLCR_DISTR2 |
+				      CDLCR_DISTR3 | CDLCR_DISTR4);
+
+	/* Set channel distribution */
+	if (lvds->primary)
+		lvds_cdl1cr = CDL1CR_DEFAULT;
+
+	if (lvds->secondary) {
+		lvds_cr |= CR_LKMOD;
+		lvds_cdl2cr = CDL2CR_DEFAULT;
+	}
+
+	/* Set signal polarity */
+	if (bus_flags & DRM_BUS_FLAG_DE_LOW)
+		lvds_cr |= CR_DEPOL;
+
+	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+		lvds_cr |= CR_HSPOL;
+
+	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+		lvds_cr |= CR_VSPOL;
+
+	switch (lvds->link_type) {
+	case LVDS_DUAL_LINK_EVEN_ODD_PIXELS: /* LKPHA = 0 */
+		lvds_cr &= ~CR_LKPHA;
+		break;
+	case LVDS_DUAL_LINK_ODD_EVEN_PIXELS: /* LKPHA = 1 */
+		lvds_cr |= CR_LKPHA;
+		break;
+	default:
+		drm_notice(lvds->lvds_bridge.dev, "No phase precised, setting default\n");
+		lvds_cr &= ~CR_LKPHA;
+		break;
+	}
+
+	/* Write config to registers */
+	lvds_set(lvds, LVDS_CR, lvds_cr);
+	lvds_write(lvds, LVDS_CDL1CR, lvds_cdl1cr);
+	lvds_write(lvds, LVDS_CDL2CR, lvds_cdl2cr);
+}
+
+static int lvds_connector_get_modes(struct drm_connector *connector)
+{
+	struct stm_lvds *lvds = connector_to_stm_lvds(connector);
+
+	return drm_panel_get_modes(lvds->panel, connector);
+}
+
+static int lvds_connector_atomic_check(struct drm_connector *connector,
+				       struct drm_atomic_commit *state)
+{
+	const struct drm_display_mode *panel_mode;
+	struct drm_connector_state *conn_state;
+	struct drm_crtc_state *crtc_state;
+
+	conn_state = drm_atomic_get_new_connector_state(state, connector);
+	if (!conn_state)
+		return -EINVAL;
+
+	if (!conn_state->crtc)
+		return 0;
+
+	if (list_empty(&connector->modes)) {
+		drm_dbg(connector->dev, "connector: empty modes list\n");
+		return -EINVAL;
+	}
+
+	panel_mode = list_first_entry(&connector->modes,
+				      struct drm_display_mode, head);
+
+	/* We're not allowed to modify the resolution. */
+	crtc_state = drm_atomic_get_crtc_state(state, conn_state->crtc);
+	if (IS_ERR(crtc_state))
+		return PTR_ERR(crtc_state);
+
+	if (crtc_state->mode.hdisplay != panel_mode->hdisplay ||
+	    crtc_state->mode.vdisplay != panel_mode->vdisplay)
+		return -EINVAL;
+
+	/* The flat panel mode is fixed, just copy it to the adjusted mode. */
+	drm_mode_copy(&crtc_state->adjusted_mode, panel_mode);
+
+	return 0;
+}
+
+static const struct drm_connector_helper_funcs lvds_conn_helper_funcs = {
+	.get_modes = lvds_connector_get_modes,
+	.atomic_check = lvds_connector_atomic_check,
+};
+
+static const struct drm_connector_funcs lvds_conn_funcs = {
+	.reset = drm_atomic_helper_connector_reset,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static int lvds_attach(struct drm_bridge *bridge, struct drm_encoder *encoder,
+		       enum drm_bridge_attach_flags flags)
+{
+	struct stm_lvds *lvds = bridge_to_stm_lvds(bridge);
+	struct drm_connector *connector = &lvds->connector;
+	int ret;
+
+	if (!encoder) {
+		drm_err(bridge->dev, "Parent encoder object not found\n");
+		return -ENODEV;
+	}
+
+	/* Set the encoder type as caller does not know it */
+	encoder->encoder_type = DRM_MODE_ENCODER_LVDS;
+
+	/* No cloning support */
+	encoder->possible_clones = 0;
+
+	/* If we have a next bridge just attach it. */
+	if (lvds->next_bridge)
+		return drm_bridge_attach(encoder, lvds->next_bridge,
+					 bridge, flags);
+
+	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
+		drm_err(bridge->dev, "Fix bridge driver to make connector optional!");
+		return -EINVAL;
+	}
+
+	/* Otherwise if we have a panel, create a connector. */
+	if (!lvds->panel)
+		return 0;
+
+	ret = drm_connector_init(bridge->dev, connector,
+				 &lvds_conn_funcs, DRM_MODE_CONNECTOR_LVDS);
+	if (ret < 0)
+		return ret;
+
+	drm_connector_helper_add(connector, &lvds_conn_helper_funcs);
+
+	ret = drm_connector_attach_encoder(connector, encoder);
+
+	return ret;
+}
+
+static void lvds_atomic_enable(struct drm_bridge *bridge,
+			       struct drm_atomic_commit *state)
+{
+	struct stm_lvds *lvds = bridge_to_stm_lvds(bridge);
+	struct drm_connector_state *conn_state;
+	struct drm_connector *connector;
+	int ret;
+
+	ret = clk_prepare_enable(lvds->pclk);
+	if (ret) {
+		drm_err(bridge->dev, "Failed to enable lvds peripheral clk\n");
+		return;
+	}
+
+	connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
+	if (!connector)
+		return;
+
+	conn_state = drm_atomic_get_new_connector_state(state, connector);
+	if (!conn_state)
+		return;
+
+	lvds_config_mode(lvds);
+
+	/* Set Data Mapping */
+	lvds_config_data_mapping(lvds);
+
+	/* Turn the output on. */
+	lvds_set(lvds, LVDS_CR, CR_LVDSEN);
+
+	if (lvds->panel) {
+		drm_panel_prepare(lvds->panel);
+		drm_panel_enable(lvds->panel);
+	}
+}
+
+static void lvds_atomic_disable(struct drm_bridge *bridge,
+				struct drm_atomic_commit *state)
+{
+	struct stm_lvds *lvds = bridge_to_stm_lvds(bridge);
+
+	if (lvds->panel) {
+		drm_panel_disable(lvds->panel);
+		drm_panel_unprepare(lvds->panel);
+	}
+
+	/* Disable LVDS module */
+	lvds_clear(lvds, LVDS_CR, CR_LVDSEN);
+
+	clk_disable_unprepare(lvds->pclk);
+}
+
+static const struct drm_bridge_funcs lvds_bridge_funcs = {
+	.attach = lvds_attach,
+	.atomic_enable = lvds_atomic_enable,
+	.atomic_disable = lvds_atomic_disable,
+	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+	.atomic_create_state = drm_atomic_helper_bridge_create_state,
+};
+
+static int lvds_probe(struct platform_device *pdev)
+{
+	struct device_node *port1, *port2, *remote;
+	struct device *dev = &pdev->dev;
+	struct reset_control *rstc;
+	struct stm_lvds *lvds;
+	int ret, dual_link;
+
+	dev_dbg(dev, "Probing LVDS driver...\n");
+
+	lvds = devm_drm_bridge_alloc(dev, struct stm_lvds, lvds_bridge, &lvds_bridge_funcs);
+	if (IS_ERR(lvds))
+		return PTR_ERR(lvds);
+
+	lvds->dev = dev;
+
+	ret = drm_of_find_panel_or_bridge(dev->of_node, 1, 0,
+					  &lvds->panel, &lvds->next_bridge);
+	if (ret) {
+		dev_err_probe(dev, ret, "Panel not found\n");
+		return ret;
+	}
+
+	lvds->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(lvds->base)) {
+		ret = PTR_ERR(lvds->base);
+		dev_err(dev, "Unable to get regs %d\n", ret);
+		goto err_put_panel;
+	}
+
+	lvds->pclk = devm_clk_get(dev, "pclk");
+	if (IS_ERR(lvds->pclk)) {
+		ret = PTR_ERR(lvds->pclk);
+		dev_err(dev, "Unable to get peripheral clock: %d\n", ret);
+		goto err_put_panel;
+	}
+
+	ret = clk_prepare_enable(lvds->pclk);
+	if (ret) {
+		dev_err(dev, "%s: Failed to enable peripheral clk\n", __func__);
+		goto err_put_panel;
+	}
+
+	rstc = devm_reset_control_get_exclusive(dev, NULL);
+
+	if (IS_ERR(rstc)) {
+		ret = PTR_ERR(rstc);
+		goto err_lvds_probe;
+	}
+
+	reset_control_assert(rstc);
+	usleep_range(10, 20);
+	reset_control_deassert(rstc);
+
+	port1 = of_graph_get_port_by_id(dev->of_node, 1);
+	port2 = of_graph_get_port_by_id(dev->of_node, 2);
+	dual_link = drm_of_lvds_get_dual_link_pixel_order(port1, port2);
+
+	switch (dual_link) {
+	case DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS:
+		lvds->link_type = LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
+		lvds->primary = &lvds_phy_16ff_primary;
+		lvds->secondary = &lvds_phy_16ff_secondary;
+		break;
+	case DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS:
+		lvds->link_type = LVDS_DUAL_LINK_EVEN_ODD_PIXELS;
+		lvds->primary = &lvds_phy_16ff_primary;
+		lvds->secondary = &lvds_phy_16ff_secondary;
+		break;
+	case -EINVAL:
+		/*
+		 * drm_of_lvds_get_dual_pixel_order returns 4 possible values.
+		 * In the case where the returned value is an error, it can be
+		 * either ENODEV or EINVAL. Seeing the structure of this
+		 * function, EINVAL means that either port1 or port2 is not
+		 * present in the device tree.
+		 * In that case, the lvds panel can be a single link panel, or
+		 * there is a semantical error in the device tree code.
+		 */
+		remote = of_get_next_available_child(port1, NULL);
+		if (remote) {
+			if (of_graph_get_remote_endpoint(remote)) {
+				lvds->link_type = LVDS_SINGLE_LINK_PRIMARY;
+				lvds->primary = &lvds_phy_16ff_primary;
+				lvds->secondary = NULL;
+			} else {
+				ret = -EINVAL;
+			}
+
+			of_node_put(remote);
+		}
+
+		remote = of_get_next_available_child(port2, NULL);
+		if (remote) {
+			if (of_graph_get_remote_endpoint(remote)) {
+				lvds->link_type = LVDS_SINGLE_LINK_SECONDARY;
+				lvds->primary = NULL;
+				lvds->secondary = &lvds_phy_16ff_secondary;
+			} else {
+				ret = (ret == -EINVAL) ? -EINVAL : 0;
+			}
+
+			of_node_put(remote);
+		}
+		break;
+	default:
+		ret = -EINVAL;
+		goto err_lvds_probe;
+	}
+	of_node_put(port1);
+	of_node_put(port2);
+
+	lvds->pllref_clk = devm_clk_get(dev, "ref");
+	if (IS_ERR(lvds->pllref_clk)) {
+		ret = PTR_ERR(lvds->pllref_clk);
+		dev_err(dev, "Unable to get reference clock: %d\n", ret);
+		goto err_lvds_probe;
+	}
+
+	ret = lvds_pixel_clk_register(lvds);
+	if (ret) {
+		dev_err(dev, "Failed to register LVDS pixel clock: %d\n", ret);
+		goto err_lvds_probe;
+	}
+
+	lvds->lvds_bridge.of_node = dev->of_node;
+	lvds->hw_version = lvds_read(lvds, LVDS_VERR);
+
+	dev_info(dev, "version 0x%02x initialized\n", lvds->hw_version);
+
+	drm_bridge_add(&lvds->lvds_bridge);
+
+	platform_set_drvdata(pdev, lvds);
+
+	clk_disable_unprepare(lvds->pclk);
+
+	return 0;
+
+err_lvds_probe:
+	clk_disable_unprepare(lvds->pclk);
+err_put_panel:
+	if (lvds->panel)
+		drm_panel_put(lvds->panel);
+
+	return ret;
+}
+
+static void lvds_remove(struct platform_device *pdev)
+{
+	struct stm_lvds *lvds = platform_get_drvdata(pdev);
+
+	if (lvds->panel)
+		drm_panel_put(lvds->panel);
+
+	lvds_pixel_clk_unregister(lvds);
+
+	drm_bridge_remove(&lvds->lvds_bridge);
+}
+
+static const struct of_device_id lvds_dt_ids[] = {
+	{
+		.compatible = "st,stm32mp25-lvds",
+		.data = NULL
+	},
+	{ /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, lvds_dt_ids);
+
+static struct platform_driver lvds_platform_driver = {
+	.probe = lvds_probe,
+	.remove = lvds_remove,
+	.driver = {
+		.name = "stm32-display-lvds",
+		.of_match_table = lvds_dt_ids,
+	},
+};
+
+module_platform_driver(lvds_platform_driver);
+
+MODULE_AUTHOR("Raphaël Gallais-Pou <raphael.gallais-pou@foss.st.com>");
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@foss.st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@foss.st.com>");
+MODULE_DESCRIPTION("STMicroelectronics LVDS Display Interface Transmitter DRM driver");
+MODULE_LICENSE("GPL");
-- 
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