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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/backlight/<backlight>/scale
+Date: July 2019
+KernelVersion: 5.4
+Contact: Daniel Thompson <daniel.thompson@linaro.org>
+Description:
+ Description of the scale of the brightness curve.
+
+ The human eye senses brightness approximately logarithmically,
+ hence linear changes in brightness are perceived as being
+ non-linear. To achieve a linear perception of brightness changes
+ controls like sliders need to apply a logarithmic mapping for
+ backlights with a linear brightness curve.
+
+ Possible values of the attribute are:
+
+ unknown
+ The scale of the brightness curve is unknown.
+
+ linear
+ The brightness changes linearly with each step. Brightness
+ controls should apply a logarithmic mapping for a linear
+ perception.
+
+ non-linear
+ The brightness changes non-linearly with each step. Brightness
+ controls should use a linear mapping for a linear perception.
+
+What: /sys/class/backlight/<backlight>/ambient_light_level
+Date: Apr, 2010
+KernelVersion: v2.6.35
+Contact: Michael Hennerich <michael.hennerich@analog.com>
+Description:
+ (RO) Get conversion value of the light sensor.
+
+ The value is automatically updated every 80 ms when the
+ light sensor is enabled.
+
+ The value range is device-driver specific:
+
+ For ADP8870:
+
+ It returns integer between 0 (dark) and 8000 (max ambient
+ brightness).
+
+ For ADP8860:
+
+ It returns a 13-bits integer.
+
+What: /sys/class/backlight/<backlight>/ambient_light_zone
+Date: Apr, 2010
+KernelVersion: v2.6.35
+Contact: Michael Hennerich <michael.hennerich@analog.com>,
+ device-drivers-devel@blackfin.uclinux.org
+
+Description:
+ (RW) Read or write the specific brightness level at which the
+ backlight operates.
+
+ The value meaning is device-driver specific:
+
+ For ADP8860:
+
+ == ==========================
+ 0 Off: Backlight set to 0 mA
+ 1 Level 1: daylight
+ 2 Level 2: bright
+ 3 Level 3: dark
+ == ==========================
+
+ For ADP8870:
+
+ == ==========================
+ 0 Off: Backlight set to 0 mA
+ 1 Level 1: daylight
+ 2 Level 2: bright
+ 3 Level 3: office
+ 4 Level 4: indoor
+ 5 Level 5: dark
+ == ==========================
+
+ Writing 0 returns to normal/automatic ambient light level
+ operation.
+
+ It can be enabled by writing the value stored in
+ /sys/class/backlight/<backlight>/max_brightness to
+ /sys/class/backlight/<backlight>/brightness.
+
+What: /sys/class/backlight/<backlight>/<ambient light zone>_max
+Date: Sep, 2009
+KernelVersion: v2.6.32
+Contact: device-drivers-devel@blackfin.uclinux.org
+Description:
+ Control the maximum brightness for <ambient light zone>
+ on this <backlight>. Values are between 0 and 127. This file
+ will also show the brightness level stored for this
+ <ambient light zone>.
+
+ The <ambient light zone> is device-driver specific:
+
+ For ADP5520 and ADP5501, <ambient light zone> can be:
+
+ =========== ================================================
+ Ambient sysfs entry
+ light zone
+ =========== ================================================
+ daylight /sys/class/backlight/<backlight>/daylight_max
+ office /sys/class/backlight/<backlight>/office_max
+ dark /sys/class/backlight/<backlight>/dark_max
+ =========== ================================================
+
+ For ADP8860, <ambient light zone> can be:
+
+ =========== ================================================
+ Ambient sysfs entry
+ light zone
+ =========== ================================================
+ l1_daylight /sys/class/backlight/<backlight>/l1_daylight_max
+ l2_office /sys/class/backlight/<backlight>/l2_office_max
+ l3_dark /sys/class/backlight/<backlight>/l3_dark_max
+ =========== ================================================
+
+ For ADP8870, <ambient light zone> can be:
+
+ =========== ================================================
+ Ambient sysfs entry
+ light zone
+ =========== ================================================
+ l1_daylight /sys/class/backlight/<backlight>/l1_daylight_max
+ l2_bright /sys/class/backlight/<backlight>/l2_bright_max
+ l3_office /sys/class/backlight/<backlight>/l3_office_max
+ l4_indoor /sys/class/backlight/<backlight>/l4_indoor_max
+ l5_dark /sys/class/backlight/<backlight>/l5_dark_max
+ =========== ================================================
+
+ See also: /sys/class/backlight/<backlight>/ambient_light_zone.
+
+What: /sys/class/backlight/<backlight>/<ambient light zone>_dim
+Date: Sep, 2009
+KernelVersion: v2.6.32
+Contact: device-drivers-devel@blackfin.uclinux.org
+Description:
+ Control the dim brightness for <ambient light zone>
+ on this <backlight>. Values are between 0 and 127, typically
+ set to 0. Full off when the backlight is disabled.
+ This file will also show the dim brightness level stored for
+ this <ambient light zone>.
+
+ The <ambient light zone> is device-driver specific:
+
+ For ADP5520 and ADP5501, <ambient light zone> can be:
+
+ =========== ================================================
+ Ambient sysfs entry
+ light zone
+ =========== ================================================
+ daylight /sys/class/backlight/<backlight>/daylight_dim
+ office /sys/class/backlight/<backlight>/office_dim
+ dark /sys/class/backlight/<backlight>/dark_dim
+ =========== ================================================
+
+ For ADP8860, <ambient light zone> can be:
+
+ =========== ================================================
+ Ambient sysfs entry
+ light zone
+ =========== ================================================
+ l1_daylight /sys/class/backlight/<backlight>/l1_daylight_dim
+ l2_office /sys/class/backlight/<backlight>/l2_office_dim
+ l3_dark /sys/class/backlight/<backlight>/l3_dark_dim
+ =========== ================================================
+
+ For ADP8870, <ambient light zone> can be:
+
+ =========== ================================================
+ Ambient sysfs entry
+ light zone
+ =========== ================================================
+ l1_daylight /sys/class/backlight/<backlight>/l1_daylight_dim
+ l2_bright /sys/class/backlight/<backlight>/l2_bright_dim
+ l3_office /sys/class/backlight/<backlight>/l3_office_dim
+ l4_indoor /sys/class/backlight/<backlight>/l4_indoor_dim
+ l5_dark /sys/class/backlight/<backlight>/l5_dark_dim
+ =========== ================================================
+
+ See also: /sys/class/backlight/<backlight>/ambient_light_zone.
+