^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) What: /sys/class/backlight/<backlight>/scale
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) Date: July 2019
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) KernelVersion: 5.4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) Contact: Daniel Thompson <daniel.thompson@linaro.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) Description:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) Description of the scale of the brightness curve.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) The human eye senses brightness approximately logarithmically,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) hence linear changes in brightness are perceived as being
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) non-linear. To achieve a linear perception of brightness changes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) controls like sliders need to apply a logarithmic mapping for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) backlights with a linear brightness curve.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) Possible values of the attribute are:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) unknown
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) The scale of the brightness curve is unknown.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) linear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) The brightness changes linearly with each step. Brightness
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) controls should apply a logarithmic mapping for a linear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) perception.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) non-linear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) The brightness changes non-linearly with each step. Brightness
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) controls should use a linear mapping for a linear perception.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) What: /sys/class/backlight/<backlight>/ambient_light_level
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) Date: Apr, 2010
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) KernelVersion: v2.6.35
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) Contact: Michael Hennerich <michael.hennerich@analog.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) Description:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) (RO) Get conversion value of the light sensor.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) The value is automatically updated every 80 ms when the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) light sensor is enabled.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) The value range is device-driver specific:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) For ADP8870:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) It returns integer between 0 (dark) and 8000 (max ambient
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) brightness).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) For ADP8860:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) It returns a 13-bits integer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) What: /sys/class/backlight/<backlight>/ambient_light_zone
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) Date: Apr, 2010
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) KernelVersion: v2.6.35
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) Contact: Michael Hennerich <michael.hennerich@analog.com>,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) device-drivers-devel@blackfin.uclinux.org
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) Description:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) (RW) Read or write the specific brightness level at which the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) backlight operates.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) The value meaning is device-driver specific:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) For ADP8860:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) == ==========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 0 Off: Backlight set to 0 mA
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 1 Level 1: daylight
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 2 Level 2: bright
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 3 Level 3: dark
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) == ==========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) For ADP8870:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) == ==========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 0 Off: Backlight set to 0 mA
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 1 Level 1: daylight
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 2 Level 2: bright
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 3 Level 3: office
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 4 Level 4: indoor
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 5 Level 5: dark
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) == ==========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) Writing 0 returns to normal/automatic ambient light level
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) operation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) It can be enabled by writing the value stored in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) /sys/class/backlight/<backlight>/max_brightness to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) /sys/class/backlight/<backlight>/brightness.
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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