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.