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authorMauro Carvalho Chehab <mchehab+huawei@kernel.org>2020-10-30 10:40:56 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-10-30 15:15:01 +0300
commitbd6e8441c2fc4d653d115516f55b1700284bc42d (patch)
tree05b59791d0700d079f787b293590cf9ea805e7c7 /Documentation
parent1b3023ef54d4fc8e8a034d2178ef80bddd7ba206 (diff)
downloadlinux-bd6e8441c2fc4d653d115516f55b1700284bc42d.tar.xz
docs: ABI: sysfs-class-backlight: unify ABI documentation
Both adp8860 and adp8870 define some extensions to the backlight class. This causes warnings: Warning: /sys/class/backlight/<backlight>/ambient_light_level is defined 2 times: /sys/class/backlight/<backlight>/ambient_light_level:8 /sys/class/backlight/<backlight>/ambient_light_level:30 Warning: /sys/class/backlight/<backlight>/ambient_light_zone is defined 2 times: /sys/class/backlight/<backlight>/ambient_light_zone:18 /sys/class/backlight/<backlight>/ambient_light_zone:40 As ABI definitions shouldn't be duplicated. Unfortunately, the ABI is dependent on the specific device features. As such, ambient_light_level range is somewhat different among the supported devices. The ambient_light_zone is even worse: the meanings of each preset are different, and there's no ABI to retrieve the supported types nor their meanins. Unfortunately, it is too late to fix it without causing regressions, as this has been used since Kernel v2.6.35. Rewrite those ABI documentation using the current documentation as a reference, and double-checking at the datasheets: https://www.analog.com/media/en/technical-documentation/data-sheets/ADP8870.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/ADP8860.pdf in order to properly document the differences between those two drivers. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/342195ad5a819d9bcfcebc133c77ab69b4211672.1604042072.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-class-backlight60
-rw-r--r--Documentation/ABI/testing/sysfs-class-backlight-adp886021
-rw-r--r--Documentation/ABI/testing/sysfs-class-backlight-driver-adp887030
3 files changed, 65 insertions, 46 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-backlight b/Documentation/ABI/testing/sysfs-class-backlight
index 3ab175a3f5cb..1fc86401bf95 100644
--- a/Documentation/ABI/testing/sysfs-class-backlight
+++ b/Documentation/ABI/testing/sysfs-class-backlight
@@ -24,3 +24,63 @@ Description:
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.
diff --git a/Documentation/ABI/testing/sysfs-class-backlight-adp8860 b/Documentation/ABI/testing/sysfs-class-backlight-adp8860
index 54d61c788b1b..6610ac73f9ba 100644
--- a/Documentation/ABI/testing/sysfs-class-backlight-adp8860
+++ b/Documentation/ABI/testing/sysfs-class-backlight-adp8860
@@ -6,25 +6,8 @@ adp8860, adp8861 and adp8863 devices: daylight (level 1), office (level 2) and
dark (level 3). By default the brightness operates at the daylight brightness
level.
-What: /sys/class/backlight/<backlight>/ambient_light_level
-Date: Apr, 2010
-KernelVersion: v2.6.35
-Contact: Michael Hennerich <michael.hennerich@analog.com>
-Description:
- (RO) 13-bit conversion value for the first light sensor—high
- byte (Bit 12 to Bit 8). The value is updated every 80 ms (when
- the light sensor is enabled).
-
-
-What: /sys/class/backlight/<backlight>/ambient_light_zone
-Date: Apr, 2010
-KernelVersion: v2.6.35
-Contact: Michael Hennerich <michael.hennerich@analog.com>
-Description:
- (RW) Read or write the specific level at which the backlight
- operates. Value "0" enables automatic ambient light sensing, and
- values "1", "2" or "3" set the control to daylight, office or
- dark respectively.
+See also /sys/class/backlight/<backlight>/ambient_light_level and
+/sys/class/backlight/<backlight>/ambient_light_zone.
What: /sys/class/backlight/<backlight>/l1_daylight_max
diff --git a/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870 b/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870
index 33e648808117..b08ca912cad4 100644
--- a/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870
+++ b/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870
@@ -1,3 +1,6 @@
+See also /sys/class/backlight/<backlight>/ambient_light_level and
+/sys/class/backlight/<backlight>/ambient_light_zone.
+
What: /sys/class/backlight/<backlight>/<ambient light zone>_max
What: /sys/class/backlight/<backlight>/l1_daylight_max
What: /sys/class/backlight/<backlight>/l2_bright_max
@@ -27,30 +30,3 @@ Description:
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>.
-
-What: /sys/class/backlight/<backlight>/ambient_light_level
-Date: May 2011
-KernelVersion: 3.0
-Contact: device-drivers-devel@blackfin.uclinux.org
-Description:
- Get conversion value of the light sensor.
- This value is updated every 80 ms (when the light sensor
- is enabled). Returns integer between 0 (dark) and
- 8000 (max ambient brightness)
-
-What: /sys/class/backlight/<backlight>/ambient_light_zone
-Date: May 2011
-KernelVersion: 3.0
-Contact: device-drivers-devel@blackfin.uclinux.org
-Description:
- Get/Set current ambient light zone. Reading returns
- integer between 1..5 (1 = daylight, 2 = bright, ..., 5 = dark).
- Writing a value between 1..5 forces the backlight controller
- to enter the corresponding ambient light zone.
- Writing 0 returns to normal/automatic ambient light level
- operation. The ambient light sensing feature on these devices
- is an extension to the API documented in
- Documentation/ABI/stable/sysfs-class-backlight.
- It can be enabled by writing the value stored in
- /sys/class/backlight/<backlight>/max_brightness to
- /sys/class/backlight/<backlight>/brightness.