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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/mfd/atmel-flexcom.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/mfd/atmel-flexcom.c')
-rw-r--r--drivers/mfd/atmel-flexcom.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
new file mode 100644
index 000000000..d5df5466e
--- /dev/null
+++ b/drivers/mfd/atmel-flexcom.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Atmel Flexcom
+ *
+ * Copyright (C) 2015 Atmel Corporation
+ *
+ * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <dt-bindings/mfd/atmel-flexcom.h>
+
+/* I/O register offsets */
+#define FLEX_MR 0x0 /* Mode Register */
+#define FLEX_VERSION 0xfc /* Version Register */
+
+/* Mode Register bit fields */
+#define FLEX_MR_OPMODE_OFFSET (0) /* Operating Mode */
+#define FLEX_MR_OPMODE_MASK (0x3 << FLEX_MR_OPMODE_OFFSET)
+#define FLEX_MR_OPMODE(opmode) (((opmode) << FLEX_MR_OPMODE_OFFSET) & \
+ FLEX_MR_OPMODE_MASK)
+
+struct atmel_flexcom {
+ void __iomem *base;
+ u32 opmode;
+ struct clk *clk;
+};
+
+static int atmel_flexcom_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct atmel_flexcom *ddata;
+ int err;
+
+ ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
+ if (!ddata)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ddata);
+
+ err = of_property_read_u32(np, "atmel,flexcom-mode", &ddata->opmode);
+ if (err)
+ return err;
+
+ if (ddata->opmode < ATMEL_FLEXCOM_MODE_USART ||
+ ddata->opmode > ATMEL_FLEXCOM_MODE_TWI)
+ return -EINVAL;
+
+ ddata->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+ if (IS_ERR(ddata->base))
+ return PTR_ERR(ddata->base);
+
+ ddata->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(ddata->clk))
+ return PTR_ERR(ddata->clk);
+
+ err = clk_prepare_enable(ddata->clk);
+ if (err)
+ return err;
+
+ /*
+ * Set the Operating Mode in the Mode Register: only the selected device
+ * is clocked. Hence, registers of the other serial devices remain
+ * inaccessible and are read as zero. Also the external I/O lines of the
+ * Flexcom are muxed to reach the selected device.
+ */
+ writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base + FLEX_MR);
+
+ clk_disable_unprepare(ddata->clk);
+
+ return devm_of_platform_populate(&pdev->dev);
+}
+
+static const struct of_device_id atmel_flexcom_of_match[] = {
+ { .compatible = "atmel,sama5d2-flexcom" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
+
+static int __maybe_unused atmel_flexcom_resume_noirq(struct device *dev)
+{
+ struct atmel_flexcom *ddata = dev_get_drvdata(dev);
+ int err;
+ u32 val;
+
+ err = clk_prepare_enable(ddata->clk);
+ if (err)
+ return err;
+
+ val = FLEX_MR_OPMODE(ddata->opmode);
+ writel(val, ddata->base + FLEX_MR);
+
+ clk_disable_unprepare(ddata->clk);
+
+ return 0;
+}
+
+static const struct dev_pm_ops __maybe_unused atmel_flexcom_pm_ops = {
+ .resume_noirq = atmel_flexcom_resume_noirq,
+};
+
+static struct platform_driver atmel_flexcom_driver = {
+ .probe = atmel_flexcom_probe,
+ .driver = {
+ .name = "atmel_flexcom",
+ .pm = pm_ptr(&atmel_flexcom_pm_ops),
+ .of_match_table = atmel_flexcom_of_match,
+ },
+};
+
+module_platform_driver(atmel_flexcom_driver);
+
+MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
+MODULE_DESCRIPTION("Atmel Flexcom MFD driver");
+MODULE_LICENSE("GPL v2");