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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
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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 ...
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+What: /sys/class/leds/<led>/brightness
+Date: March 2006
+KernelVersion: 2.6.17
+Contact: Richard Purdie <rpurdie@rpsys.net>
+Description:
+ Set the brightness of the LED.
+
+ Most LEDs don't have hardware brightness support, so will
+ just be turned on for non-zero brightness settings.
+
+ .. Note::
+
+ For multicolor LEDs, writing to this file will update all
+ LEDs within the group to a calculated percentage of what
+ each color LED intensity is set to.
+
+ The percentage is calculated for each grouped LED via
+ the equation below::
+
+ led_brightness = brightness * multi_intensity/max_brightness
+
+ For additional details please refer to
+ Documentation/leds/leds-class-multicolor.rst.
+
+ The value is between 0 and /sys/class/leds/<led>/max_brightness
+ and is represented by as a decimal.
+
+ Writing 0 to this file clears active trigger.
+
+ Writing non-zero to this file while trigger is active changes the
+ top brightness trigger is going to use.
+
+
+
+What: /sys/class/leds/<led>/max_brightness
+Date: March 2006
+KernelVersion: 2.6.17
+Contact: Richard Purdie <rpurdie@rpsys.net>
+Description:
+ Maximum brightness level for this LED, default is 255 (LED_FULL).
+
+ If the LED does not support different brightness levels, this
+ should be 1.
+
+What: /sys/class/leds/<led>/brightness_hw_changed
+Date: January 2017
+KernelVersion: 4.11
+Description:
+ Last hardware set brightness level for this LED. Some LEDs
+ may be changed autonomously by hardware/firmware. Only LEDs
+ where this happens and the driver can detect this, will have
+ this file.
+
+ This file supports poll() to detect when the hardware changes
+ the brightness.
+
+ Reading this file will return the last brightness level set
+ by the hardware, this may be different from the current
+ brightness. Reading this file when no hw brightness change
+ event has happened will return an ENODATA error.
+
+What: /sys/class/leds/<led>/trigger
+Date: March 2006
+KernelVersion: 2.6.17
+Contact: Richard Purdie <rpurdie@rpsys.net>
+Description:
+ Set the trigger for this LED. A trigger is a kernel based source
+ of LED events.
+
+ You can change triggers in a similar manner to the way an IO
+ scheduler is chosen. Trigger specific parameters can appear in
+ /sys/class/leds/<led> once a given trigger is selected. For
+ their documentation see `sysfs-class-led-trigger-*`.
+
+ Writing "none" removes the trigger for this LED.
+
+ Writing "default" sets the trigger to the LED's default trigger
+ (which would often be configured in the device tree for the
+ hardware).
+
+What: /sys/class/leds/<led>/inverted
+Date: January 2011
+KernelVersion: 2.6.38
+Contact: Richard Purdie <rpurdie@rpsys.net>
+Description:
+ Invert the LED on/off state. This parameter is specific to
+ gpio and backlight triggers. In case of the backlight trigger,
+ it is useful when driving a LED which is intended to indicate
+ a device in a standby like state.