Merge tag 'leds-next-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/leds

Pull LED updates from Lee Jones:
 "New Support & Features:
   - Core: Add `led_trigger_notify_hw_control_changed()` to allow
     drivers to notify the core of autonomous hardware control
     transitions
   - Core: Add the `hw_offloaded()` trigger callback and
     `trigger_may_offload_to_hw` sysfs attribute to expose
     hardware-offloaded triggers
   - Netdev Trigger: Implement the `hw_offloaded()` callback to report
     hardware control state to the LED core
   - Analog Devices LTC3208: Add support for the LTC3208 7-channel
     multi-display I2C LED driver
   - ChromeOS EC: Implement the `hw_offloaded()` callback for the
     `chromeos-auto` trigger
   - CZ.NIC Turris Omnia: Implement the `hw_offloaded()` callback and
     declare `omnia-mcu` as a hardware control trigger
   - STMicroelectronics ST1202: Add hardware-accelerated blink support
     via `blink_set()`

  Improvements & Fixes:
   - Class: Always hold the `led_access` mutex in `brightness_show()` to
     avoid exposing transient registration states
   - Class: Deactivate active hardware control triggers when writing to
     the `brightness` sysfs attribute
   - Core: Enforce strict validation in `led_trigger_is_hw_controlled()`
     and warn on legacy fallback paths
   - Flash Class: Initialize the fault variable in `flash_fault_show()`
     to prevent undefined behavior when callbacks perform bitwise ORs
   - Kinetic KTD2692: Pass the driver context directly to
     `regulator_disable_action()` to prevent a NULL pointer dereference
     during error unwinding
   - Maxim MAX77705: Use `fwnode_for_each_child_node_scoped()` in
     `max77705_add_led()` to prevent child node reference leaks on error
     paths
   - NXP PCA9532: Check the return value of `i2c_smbus_read_byte_data()`
     in `pca9532_getled()` to avoid integer underflow on read errors
   - Qualcomm WLED: Fix a NULL pointer dereference in `wled_remove()` by
     setting platform driver data in `wled_probe()`
   - Qualcomm WLED: Fix the WLED3 brightness register stride to prevent
     consecutive string writes from overlapping
   - Qualcomm WLED: Read back the hardware-programmed brightness at
     probe, expose it via `get_brightness()`, and prevent unbalanced OVP
     IRQ enabling
   - STMicroelectronics ST1202: Clear unused PWM pattern slots in
     `pattern_set()` and `blink_set()` to prevent unintended output when
     sharing the global sequencer
   - STMicroelectronics ST1202: Program and cap the channel current
     according to `max_brightness` across brightness, blink, and
     hardware pattern modes, and scale pattern brightness to the 12-bit
     PWM range
   - STMicroelectronics ST1202: Retain a reference to each child LED
     firmware node for the lifetime of the device
   - STMicroelectronics ST1202: Use only the blocking
     `brightness_set_blocking()` callback to avoid sleeping in atomic
     context during I2C transfers
   - TI LM3692x: Check the final register write in
     `lm3692x_leds_enable()` to prevent regulator/GPIO leaks and an
     inconsistent enabled state
   - TI LP8860: Fix a `device_node` reference leak in `lp8860_probe()`
     using `__free(device_node)`

  Cleanups & Refactoring:
   - Core: Move `led_trigger_is_hw_controlled()` and `led_trigger_group`
     from `led-class.c` into `led-triggers.c`
   - Core: Replace conditional `set_bit()`/`clear_bit()` patterns with
     `assign_bit()` and `__assign_bit()`
   - Flash Class: Simplify `flash_fault_show()` using `sysfs_emit_at()`
     and omit the trailing space
   - Maintainers: Add Griffin Kroah-Hartman as an LED subsystem reviewer
   - Intel SS4200: Fix a spelling typo in a comment
   - ISSI IS31FL32xx: Convert DT-specific parsing helpers to generic
     device and fwnode property APIs
   - NXP PCA955x: Drop redundant intermediate platform data and allocate
     the LED array using a flexible array member
   - Qualcomm LPG: Convert LED and channel parsing to fwnode APIs and
     avoid leaving `default_trigger` uninitialized
   - Skyworks AAT1290: Use `ARRAY_SIZE()` when allocating
     `mm_current_scale` to match the target pointer type for type-aware
     allocators
   - STMicroelectronics ST1202: Introduce a `st1202_iled_max()` helper
     to unify channel current ceiling calculations
   - STMicroelectronics ST1202: Standardize variable and macro naming,
     fix helper spelling, and use `u8` consistently instead of `uint8_t`
   - Syscon: Convert from OF-specific property helpers to the generic
     device property and fwnode APIs

  Device Tree Binding Updates:
   - Core: Allow PHY RX triggers (`phy[0-9]+rx`) in
     `linux,default-trigger`
   - Core: Standardize example indentation across multiple LED and
     backlight binding schemas
   - Analog Devices LTC3208: Document the LTC3208 multi-display LED
     driver
   - LaCie netxbig: Convert LED bindings to DT schema
   - Motorola CPCAP: Convert LED bindings to DT schemaLEDs for v7.4"

* tag 'leds-next-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/leds: (49 commits)
  dt-bindings: leds: lacie,netxbig-leds: Convert to DT schema
  leds: pca955x: Drop platform data and allocate LEDs with the device
  dt-bindings: leds: Use consistent indentation in the example
  backlight: qcom-wled: Read back the programmed brightness at probe
  backlight: qcom-wled: Fix unbalanced OVP IRQ enable at probe
  backlight: qcom-wled: Fix WLED3 brightness register stride
  backlight: qcom-wled: Fix NULL pointer dereference in wled_remove()
  dt-bindings: leds: Allow PHY RX triggers
  MAINTAINERS: Add myself as a LED SUBSYSTEM reviewer
  leds: trigger: Add led_trigger_notify_hw_control_changed() interface
  leds: trigger: Enforce strict checks in led_trigger_is_hw_controlled()
  leds: trigger: netdev: Implement hw_offloaded() callback
  leds: turris-omnia: Implement hw_offloaded() trigger callback and declare hw_control_trigger
  leds: cros_ec: Implement hw_offloaded() trigger callback
  leds: trigger: Add hw_offloaded() callback and provide trigger_may_offload_to_hw attribute
  leds: trigger: Move led_trigger_group to the right place
  leds: class: Remove hardware control trigger when writing brightness
  leds: trigger: Move led_trigger_is_hw_controlled() to the right place
  leds: class: Always protect brightness_show() with led_access
  dt-bindings: leds: leds-cpcap: Convert to DT schema
  ...

1 files changed, 24 insertions, 0 deletions

diff --git a/include/linux/leds.h b/include/linux/leds.h
index a515f075c29a..beaf23993063 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -109,6 +109,7 @@ struct led_classdev {
 #define LED_INIT_DEFAULT_TRIGGER BIT(23)
 #define LED_REJECT_NAME_CONFLICT BIT(24)
 #define LED_MULTI_COLOR		BIT(25)
+#define LED_TRIG_HW_CHANGED	BIT(26)
 
 	/* set_brightness_work / blink_timer flags, atomic, private. */
 	unsigned long		work_flags;
@@ -239,6 +240,11 @@ struct led_classdev {
 	struct kernfs_node	*brightness_hw_changed_kn;
 #endif
 
+#ifdef CONFIG_LEDS_TRIGGERS_HW_CHANGED
+	bool			trigger_hw_changed;
+	struct work_struct	trigger_hw_changed_work;
+#endif
+
 	/* Ensures consistent access to the LED class device */
 	struct mutex		led_access;
 };
@@ -485,6 +491,7 @@ struct led_trigger {
 	const char	 *name;
 	int		(*activate)(struct led_classdev *led_cdev);
 	void		(*deactivate)(struct led_classdev *led_cdev);
+	bool		(*hw_offloaded)(struct led_classdev *led_cdev);
 
 	/* Brightness set by led_trigger_event */
 	enum led_brightness brightness;
@@ -533,6 +540,9 @@ void led_trigger_blink_oneshot(struct led_trigger *trigger,
 void led_trigger_set_default(struct led_classdev *led_cdev);
 int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger);
 void led_trigger_remove(struct led_classdev *led_cdev);
+void led_trigger_remove_hw_control(struct led_classdev *led_cdev);
+
+bool led_trigger_is_hw_controlled(struct led_classdev *led_cdev);
 
 static inline void led_set_trigger_data(struct led_classdev *led_cdev,
 					void *trigger_data)
@@ -584,6 +594,13 @@ static inline int led_trigger_set(struct led_classdev *led_cdev,
 }
 
 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
+static inline void led_trigger_remove_hw_control(struct led_classdev *led_cdev) {}
+
+static inline bool led_trigger_is_hw_controlled(struct led_classdev *led_cdev)
+{
+	return false;
+}
+
 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {}
 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
 {
@@ -598,6 +615,13 @@ led_trigger_get_brightness(const struct led_trigger *trigger)
 
 #endif /* CONFIG_LEDS_TRIGGERS */
 
+#ifdef CONFIG_LEDS_TRIGGERS_HW_CHANGED
+void led_trigger_notify_hw_control_changed(struct led_classdev *led_cdev, bool activate);
+#else
+static inline void led_trigger_notify_hw_control_changed(struct led_classdev *led_cdev,
+							 bool activate) {}
+#endif
+
 /* Trigger specific enum */
 enum led_trigger_netdev_modes {
 	TRIGGER_NETDEV_LINK = 0,