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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/video/fbdev/vt8500lcdfb.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/video/fbdev/vt8500lcdfb.c')
-rw-r--r--drivers/video/fbdev/vt8500lcdfb.c489
1 files changed, 489 insertions, 0 deletions
diff --git a/drivers/video/fbdev/vt8500lcdfb.c b/drivers/video/fbdev/vt8500lcdfb.c
new file mode 100644
index 000000000..85c7a99a7
--- /dev/null
+++ b/drivers/video/fbdev/vt8500lcdfb.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/drivers/video/vt8500lcdfb.c
+ *
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * Based on skeletonfb.c and pxafb.c
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/wait.h>
+#include <video/of_display_timing.h>
+
+#include "vt8500lcdfb.h"
+#include "wmt_ge_rops.h"
+
+#ifdef CONFIG_OF
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/memblock.h>
+#endif
+
+
+#define to_vt8500lcd_info(__info) container_of(__info, \
+ struct vt8500lcd_info, fb)
+
+static int vt8500lcd_set_par(struct fb_info *info)
+{
+ struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+ int reg_bpp = 5; /* 16bpp */
+ int i;
+ unsigned long control0;
+
+ if (!fbi)
+ return -EINVAL;
+
+ if (info->var.bits_per_pixel <= 8) {
+ /* palettized */
+ info->var.red.offset = 0;
+ info->var.red.length = info->var.bits_per_pixel;
+ info->var.red.msb_right = 0;
+
+ info->var.green.offset = 0;
+ info->var.green.length = info->var.bits_per_pixel;
+ info->var.green.msb_right = 0;
+
+ info->var.blue.offset = 0;
+ info->var.blue.length = info->var.bits_per_pixel;
+ info->var.blue.msb_right = 0;
+
+ info->var.transp.offset = 0;
+ info->var.transp.length = 0;
+ info->var.transp.msb_right = 0;
+
+ info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+ info->fix.line_length = info->var.xres_virtual /
+ (8/info->var.bits_per_pixel);
+ } else {
+ /* non-palettized */
+ info->var.transp.offset = 0;
+ info->var.transp.length = 0;
+ info->var.transp.msb_right = 0;
+
+ if (info->var.bits_per_pixel == 16) {
+ /* RGB565 */
+ info->var.red.offset = 11;
+ info->var.red.length = 5;
+ info->var.red.msb_right = 0;
+ info->var.green.offset = 5;
+ info->var.green.length = 6;
+ info->var.green.msb_right = 0;
+ info->var.blue.offset = 0;
+ info->var.blue.length = 5;
+ info->var.blue.msb_right = 0;
+ } else {
+ /* Equal depths per channel */
+ info->var.red.offset = info->var.bits_per_pixel
+ * 2 / 3;
+ info->var.red.length = info->var.bits_per_pixel / 3;
+ info->var.red.msb_right = 0;
+ info->var.green.offset = info->var.bits_per_pixel / 3;
+ info->var.green.length = info->var.bits_per_pixel / 3;
+ info->var.green.msb_right = 0;
+ info->var.blue.offset = 0;
+ info->var.blue.length = info->var.bits_per_pixel / 3;
+ info->var.blue.msb_right = 0;
+ }
+
+ info->fix.visual = FB_VISUAL_TRUECOLOR;
+ info->fix.line_length = info->var.bits_per_pixel > 16 ?
+ info->var.xres_virtual << 2 :
+ info->var.xres_virtual << 1;
+ }
+
+ for (i = 0; i < 8; i++) {
+ if (bpp_values[i] == info->var.bits_per_pixel)
+ reg_bpp = i;
+ }
+
+ control0 = readl(fbi->regbase) & ~0xf;
+ writel(0, fbi->regbase);
+ while (readl(fbi->regbase + 0x38) & 0x10)
+ /* wait */;
+ writel((((info->var.hsync_len - 1) & 0x3f) << 26)
+ | ((info->var.left_margin & 0xff) << 18)
+ | (((info->var.xres - 1) & 0x3ff) << 8)
+ | (info->var.right_margin & 0xff), fbi->regbase + 0x4);
+ writel((((info->var.vsync_len - 1) & 0x3f) << 26)
+ | ((info->var.upper_margin & 0xff) << 18)
+ | (((info->var.yres - 1) & 0x3ff) << 8)
+ | (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
+ writel((((info->var.yres - 1) & 0x400) << 2)
+ | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
+ writel(0x80000000, fbi->regbase + 0x20);
+ writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
+
+ return 0;
+}
+
+static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
+{
+ chan &= 0xffff;
+ chan >>= 16 - bf->length;
+ return chan << bf->offset;
+}
+
+static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
+ unsigned blue, unsigned transp,
+ struct fb_info *info) {
+ struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+ int ret = 1;
+ unsigned int val;
+ if (regno >= 256)
+ return -EINVAL;
+
+ if (info->var.grayscale)
+ red = green = blue =
+ (19595 * red + 38470 * green + 7471 * blue) >> 16;
+
+ switch (fbi->fb.fix.visual) {
+ case FB_VISUAL_TRUECOLOR:
+ if (regno < 16) {
+ u32 *pal = fbi->fb.pseudo_palette;
+
+ val = chan_to_field(red, &fbi->fb.var.red);
+ val |= chan_to_field(green, &fbi->fb.var.green);
+ val |= chan_to_field(blue, &fbi->fb.var.blue);
+
+ pal[regno] = val;
+ ret = 0;
+ }
+ break;
+
+ case FB_VISUAL_STATIC_PSEUDOCOLOR:
+ case FB_VISUAL_PSEUDOCOLOR:
+ writew((red & 0xf800)
+ | ((green >> 5) & 0x7e0)
+ | ((blue >> 11) & 0x1f),
+ fbi->palette_cpu + sizeof(u16) * regno);
+ break;
+ }
+
+ return ret;
+}
+
+static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret = 0;
+ struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+
+ if (cmd == FBIO_WAITFORVSYNC) {
+ /* Unmask End of Frame interrupt */
+ writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
+ ret = wait_event_interruptible_timeout(fbi->wait,
+ readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
+ /* Mask back to reduce unwanted interrupt traffic */
+ writel(0xffffffff, fbi->regbase + 0x3c);
+ if (ret < 0)
+ return ret;
+ if (ret == 0)
+ return -ETIMEDOUT;
+ }
+
+ return ret;
+}
+
+static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
+ struct fb_info *info)
+{
+ unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
+ unsigned off = pixlen * var->xoffset
+ + info->fix.line_length * var->yoffset;
+ struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+
+ writel((1 << 31)
+ | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
+ | (off >> 2), fbi->regbase + 0x20);
+ return 0;
+}
+
+/*
+ * vt8500lcd_blank():
+ * Blank the display by setting all palette values to zero. Note,
+ * True Color modes do not really use the palette, so this will not
+ * blank the display in all modes.
+ */
+static int vt8500lcd_blank(int blank, struct fb_info *info)
+{
+ int i;
+
+ switch (blank) {
+ case FB_BLANK_POWERDOWN:
+ case FB_BLANK_VSYNC_SUSPEND:
+ case FB_BLANK_HSYNC_SUSPEND:
+ case FB_BLANK_NORMAL:
+ if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
+ info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
+ for (i = 0; i < 256; i++)
+ vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
+ fallthrough;
+ case FB_BLANK_UNBLANK:
+ if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
+ info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
+ fb_set_cmap(&info->cmap, info);
+ }
+ return 0;
+}
+
+static const struct fb_ops vt8500lcd_ops = {
+ .owner = THIS_MODULE,
+ __FB_DEFAULT_DMAMEM_OPS_RDWR,
+ .fb_set_par = vt8500lcd_set_par,
+ .fb_setcolreg = vt8500lcd_setcolreg,
+ .fb_fillrect = wmt_ge_fillrect,
+ .fb_copyarea = wmt_ge_copyarea,
+ .fb_imageblit = sys_imageblit,
+ .fb_sync = wmt_ge_sync,
+ .fb_ioctl = vt8500lcd_ioctl,
+ .fb_pan_display = vt8500lcd_pan_display,
+ .fb_blank = vt8500lcd_blank,
+ // .fb_mmap needs DMA mmap
+};
+
+static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
+{
+ struct vt8500lcd_info *fbi = dev_id;
+
+ if (readl(fbi->regbase + 0x38) & (1 << 3))
+ wake_up_interruptible(&fbi->wait);
+
+ writel(0xffffffff, fbi->regbase + 0x38);
+ return IRQ_HANDLED;
+}
+
+static int vt8500lcd_probe(struct platform_device *pdev)
+{
+ struct vt8500lcd_info *fbi;
+ struct resource *res;
+ struct display_timings *disp_timing;
+ void *addr;
+ int irq, ret;
+
+ struct fb_videomode of_mode;
+ u32 bpp;
+ dma_addr_t fb_mem_phys;
+ unsigned long fb_mem_len;
+ void *fb_mem_virt;
+
+ ret = -ENOMEM;
+ fbi = NULL;
+
+ fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
+ + sizeof(u32) * 16, GFP_KERNEL);
+ if (!fbi)
+ return -ENOMEM;
+
+ strcpy(fbi->fb.fix.id, "VT8500 LCD");
+
+ fbi->fb.fix.type = FB_TYPE_PACKED_PIXELS;
+ fbi->fb.fix.xpanstep = 0;
+ fbi->fb.fix.ypanstep = 1;
+ fbi->fb.fix.ywrapstep = 0;
+ fbi->fb.fix.accel = FB_ACCEL_NONE;
+
+ fbi->fb.var.nonstd = 0;
+ fbi->fb.var.activate = FB_ACTIVATE_NOW;
+ fbi->fb.var.height = -1;
+ fbi->fb.var.width = -1;
+ fbi->fb.var.vmode = FB_VMODE_NONINTERLACED;
+
+ fbi->fb.fbops = &vt8500lcd_ops;
+ fbi->fb.flags = FBINFO_HWACCEL_COPYAREA
+ | FBINFO_HWACCEL_FILLRECT
+ | FBINFO_HWACCEL_YPAN
+ | FBINFO_VIRTFB
+ | FBINFO_PARTIAL_PAN_OK;
+ fbi->fb.node = -1;
+
+ addr = fbi;
+ addr = addr + sizeof(struct vt8500lcd_info);
+ fbi->fb.pseudo_palette = addr;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "no I/O memory resource defined\n");
+ return -ENODEV;
+ }
+
+ res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
+ if (res == NULL) {
+ dev_err(&pdev->dev, "failed to request I/O memory\n");
+ return -EBUSY;
+ }
+
+ fbi->regbase = ioremap(res->start, resource_size(res));
+ if (fbi->regbase == NULL) {
+ dev_err(&pdev->dev, "failed to map I/O memory\n");
+ ret = -EBUSY;
+ goto failed_free_res;
+ }
+
+ disp_timing = of_get_display_timings(pdev->dev.of_node);
+ if (!disp_timing) {
+ ret = -EINVAL;
+ goto failed_free_io;
+ }
+
+ ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode,
+ OF_USE_NATIVE_MODE);
+ if (ret)
+ goto failed_free_io;
+
+ ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
+ if (ret)
+ goto failed_free_io;
+
+ /* try allocating the framebuffer */
+ fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
+ fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
+ GFP_KERNEL);
+ if (!fb_mem_virt) {
+ pr_err("%s: Failed to allocate framebuffer\n", __func__);
+ ret = -ENOMEM;
+ goto failed_free_io;
+ }
+
+ fbi->fb.fix.smem_start = fb_mem_phys;
+ fbi->fb.fix.smem_len = fb_mem_len;
+ fbi->fb.screen_buffer = fb_mem_virt;
+
+ fbi->palette_size = PAGE_ALIGN(512);
+ fbi->palette_cpu = dma_alloc_coherent(&pdev->dev,
+ fbi->palette_size,
+ &fbi->palette_phys,
+ GFP_KERNEL);
+ if (fbi->palette_cpu == NULL) {
+ dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
+ ret = -ENOMEM;
+ goto failed_free_mem_virt;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ ret = -ENODEV;
+ goto failed_free_palette;
+ }
+
+ ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
+ if (ret) {
+ dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
+ ret = -EBUSY;
+ goto failed_free_palette;
+ }
+
+ init_waitqueue_head(&fbi->wait);
+
+ if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
+ dev_err(&pdev->dev, "Failed to allocate color map\n");
+ ret = -ENOMEM;
+ goto failed_free_irq;
+ }
+
+ fb_videomode_to_var(&fbi->fb.var, &of_mode);
+
+ fbi->fb.var.xres_virtual = of_mode.xres;
+ fbi->fb.var.yres_virtual = of_mode.yres * 2;
+ fbi->fb.var.bits_per_pixel = bpp;
+
+ ret = vt8500lcd_set_par(&fbi->fb);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to set parameters\n");
+ goto failed_free_cmap;
+ }
+
+ writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
+ writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
+
+ platform_set_drvdata(pdev, fbi);
+
+ ret = register_framebuffer(&fbi->fb);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "Failed to register framebuffer device: %d\n", ret);
+ goto failed_free_cmap;
+ }
+
+ /*
+ * Ok, now enable the LCD controller
+ */
+ writel(readl(fbi->regbase) | 1, fbi->regbase);
+
+ return 0;
+
+failed_free_cmap:
+ if (fbi->fb.cmap.len)
+ fb_dealloc_cmap(&fbi->fb.cmap);
+failed_free_irq:
+ free_irq(irq, fbi);
+failed_free_palette:
+ dma_free_coherent(&pdev->dev, fbi->palette_size,
+ fbi->palette_cpu, fbi->palette_phys);
+failed_free_mem_virt:
+ dma_free_coherent(&pdev->dev, fbi->fb.fix.smem_len,
+ fbi->fb.screen_buffer, fbi->fb.fix.smem_start);
+failed_free_io:
+ iounmap(fbi->regbase);
+failed_free_res:
+ release_mem_region(res->start, resource_size(res));
+ return ret;
+}
+
+static void vt8500lcd_remove(struct platform_device *pdev)
+{
+ struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
+ struct resource *res;
+ int irq;
+
+ unregister_framebuffer(&fbi->fb);
+
+ writel(0, fbi->regbase);
+
+ if (fbi->fb.cmap.len)
+ fb_dealloc_cmap(&fbi->fb.cmap);
+
+ irq = platform_get_irq(pdev, 0);
+ free_irq(irq, fbi);
+
+ dma_free_coherent(&pdev->dev, fbi->palette_size,
+ fbi->palette_cpu, fbi->palette_phys);
+
+ iounmap(fbi->regbase);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(res->start, resource_size(res));
+}
+
+static const struct of_device_id via_dt_ids[] = {
+ { .compatible = "via,vt8500-fb", },
+ {}
+};
+
+static struct platform_driver vt8500lcd_driver = {
+ .probe = vt8500lcd_probe,
+ .remove = vt8500lcd_remove,
+ .driver = {
+ .name = "vt8500-lcd",
+ .of_match_table = of_match_ptr(via_dt_ids),
+ },
+};
+
+module_platform_driver(vt8500lcd_driver);
+
+MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
+MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, via_dt_ids);