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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/leds/leds-syscon.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/leds/leds-syscon.c')
-rw-r--r--drivers/leds/leds-syscon.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/leds/leds-syscon.c b/drivers/leds/leds-syscon.c
new file mode 100644
index 000000000..d633ad519
--- /dev/null
+++ b/drivers/leds/leds-syscon.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Generic Syscon LEDs Driver
+ *
+ * Copyright (c) 2014, Linaro Limited
+ * Author: Linus Walleij <linus.walleij@linaro.org>
+ */
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/leds.h>
+
+/**
+ * struct syscon_led - state container for syscon based LEDs
+ * @cdev: LED class device for this LED
+ * @map: regmap to access the syscon device backing this LED
+ * @offset: the offset into the syscon regmap for the LED register
+ * @mask: the bit in the register corresponding to the LED
+ * @state: current state of the LED
+ */
+struct syscon_led {
+ struct led_classdev cdev;
+ struct regmap *map;
+ u32 offset;
+ u32 mask;
+ bool state;
+};
+
+static void syscon_led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct syscon_led *sled =
+ container_of(led_cdev, struct syscon_led, cdev);
+ u32 val;
+ int ret;
+
+ if (value == LED_OFF) {
+ val = 0;
+ sled->state = false;
+ } else {
+ val = sled->mask;
+ sled->state = true;
+ }
+
+ ret = regmap_update_bits(sled->map, sled->offset, sled->mask, val);
+ if (ret < 0)
+ dev_err(sled->cdev.dev, "error updating LED status\n");
+}
+
+static int syscon_led_probe(struct platform_device *pdev)
+{
+ struct led_init_data init_data = {};
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev_of_node(dev);
+ struct device *parent;
+ struct regmap *map;
+ struct syscon_led *sled;
+ enum led_default_state state;
+ u32 value;
+ int ret;
+
+ parent = dev->parent;
+ if (!parent) {
+ dev_err(dev, "no parent for syscon LED\n");
+ return -ENODEV;
+ }
+ map = syscon_node_to_regmap(dev_of_node(parent));
+ if (IS_ERR(map)) {
+ dev_err(dev, "no regmap for syscon LED parent\n");
+ return PTR_ERR(map);
+ }
+
+ sled = devm_kzalloc(dev, sizeof(*sled), GFP_KERNEL);
+ if (!sled)
+ return -ENOMEM;
+
+ sled->map = map;
+
+ if (of_property_read_u32(np, "reg", &sled->offset) &&
+ of_property_read_u32(np, "offset", &sled->offset))
+ return -EINVAL;
+ if (of_property_read_u32(np, "mask", &sled->mask))
+ return -EINVAL;
+
+ init_data.fwnode = of_fwnode_handle(np);
+
+ state = led_init_default_state_get(init_data.fwnode);
+ switch (state) {
+ case LEDS_DEFSTATE_ON:
+ ret = regmap_update_bits(map, sled->offset, sled->mask, sled->mask);
+ if (ret < 0)
+ return ret;
+ sled->state = true;
+ break;
+ case LEDS_DEFSTATE_KEEP:
+ ret = regmap_read(map, sled->offset, &value);
+ if (ret < 0)
+ return ret;
+ sled->state = !!(value & sled->mask);
+ break;
+ default:
+ ret = regmap_update_bits(map, sled->offset, sled->mask, 0);
+ if (ret < 0)
+ return ret;
+ sled->state = false;
+ }
+ sled->cdev.brightness_set = syscon_led_set;
+
+ ret = devm_led_classdev_register_ext(dev, &sled->cdev, &init_data);
+ if (ret < 0)
+ return ret;
+
+ platform_set_drvdata(pdev, sled);
+ dev_info(dev, "registered LED %s\n", sled->cdev.name);
+
+ return 0;
+}
+
+static const struct of_device_id of_syscon_leds_match[] = {
+ { .compatible = "register-bit-led", },
+ {},
+};
+
+static struct platform_driver syscon_led_driver = {
+ .probe = syscon_led_probe,
+ .driver = {
+ .name = "leds-syscon",
+ .of_match_table = of_syscon_leds_match,
+ .suppress_bind_attrs = true,
+ },
+};
+builtin_platform_driver(syscon_led_driver);