0001 What: /sys/class/backlight/<backlight>/scale
0002 Date: July 2019
0003 KernelVersion: 5.4
0004 Contact: Daniel Thompson <daniel.thompson@linaro.org>
0005 Description:
0006 Description of the scale of the brightness curve.
0007
0008 The human eye senses brightness approximately logarithmically,
0009 hence linear changes in brightness are perceived as being
0010 non-linear. To achieve a linear perception of brightness changes
0011 controls like sliders need to apply a logarithmic mapping for
0012 backlights with a linear brightness curve.
0013
0014 Possible values of the attribute are:
0015
0016 unknown
0017 The scale of the brightness curve is unknown.
0018
0019 linear
0020 The brightness changes linearly with each step. Brightness
0021 controls should apply a logarithmic mapping for a linear
0022 perception.
0023
0024 non-linear
0025 The brightness changes non-linearly with each step. Brightness
0026 controls should use a linear mapping for a linear perception.
0027
0028 What: /sys/class/backlight/<backlight>/ambient_light_level
0029 Date: Apr, 2010
0030 KernelVersion: v2.6.35
0031 Contact: Michael Hennerich <michael.hennerich@analog.com>
0032 Description:
0033 (RO) Get conversion value of the light sensor.
0034
0035 The value is automatically updated every 80 ms when the
0036 light sensor is enabled.
0037
0038 The value range is device-driver specific:
0039
0040 For ADP8870:
0041
0042 It returns integer between 0 (dark) and 8000 (max ambient
0043 brightness).
0044
0045 For ADP8860:
0046
0047 It returns a 13-bits integer.
0048
0049 What: /sys/class/backlight/<backlight>/ambient_light_zone
0050 Date: Apr, 2010
0051 KernelVersion: v2.6.35
0052 Contact: Michael Hennerich <michael.hennerich@analog.com>,
0053 device-drivers-devel@blackfin.uclinux.org
0054
0055 Description:
0056 (RW) Read or write the specific brightness level at which the
0057 backlight operates.
0058
0059 The value meaning is device-driver specific:
0060
0061 For ADP8860:
0062
0063 == ==========================
0064 0 Off: Backlight set to 0 mA
0065 1 Level 1: daylight
0066 2 Level 2: bright
0067 3 Level 3: dark
0068 == ==========================
0069
0070 For ADP8870:
0071
0072 == ==========================
0073 0 Off: Backlight set to 0 mA
0074 1 Level 1: daylight
0075 2 Level 2: bright
0076 3 Level 3: office
0077 4 Level 4: indoor
0078 5 Level 5: dark
0079 == ==========================
0080
0081 Writing 0 returns to normal/automatic ambient light level
0082 operation.
0083
0084 It can be enabled by writing the value stored in
0085 /sys/class/backlight/<backlight>/max_brightness to
0086 /sys/class/backlight/<backlight>/brightness.
0087
0088 What: /sys/class/backlight/<backlight>/<ambient light zone>_max
0089 Date: Sep, 2009
0090 KernelVersion: v2.6.32
0091 Contact: device-drivers-devel@blackfin.uclinux.org
0092 Description:
0093 Control the maximum brightness for <ambient light zone>
0094 on this <backlight>. Values are between 0 and 127. This file
0095 will also show the brightness level stored for this
0096 <ambient light zone>.
0097
0098 The <ambient light zone> is device-driver specific:
0099
0100 For ADP5520 and ADP5501, <ambient light zone> can be:
0101
0102 =========== ================================================
0103 Ambient sysfs entry
0104 light zone
0105 =========== ================================================
0106 daylight /sys/class/backlight/<backlight>/daylight_max
0107 office /sys/class/backlight/<backlight>/office_max
0108 dark /sys/class/backlight/<backlight>/dark_max
0109 =========== ================================================
0110
0111 For ADP8860, <ambient light zone> can be:
0112
0113 =========== ================================================
0114 Ambient sysfs entry
0115 light zone
0116 =========== ================================================
0117 l1_daylight /sys/class/backlight/<backlight>/l1_daylight_max
0118 l2_office /sys/class/backlight/<backlight>/l2_office_max
0119 l3_dark /sys/class/backlight/<backlight>/l3_dark_max
0120 =========== ================================================
0121
0122 For ADP8870, <ambient light zone> can be:
0123
0124 =========== ================================================
0125 Ambient sysfs entry
0126 light zone
0127 =========== ================================================
0128 l1_daylight /sys/class/backlight/<backlight>/l1_daylight_max
0129 l2_bright /sys/class/backlight/<backlight>/l2_bright_max
0130 l3_office /sys/class/backlight/<backlight>/l3_office_max
0131 l4_indoor /sys/class/backlight/<backlight>/l4_indoor_max
0132 l5_dark /sys/class/backlight/<backlight>/l5_dark_max
0133 =========== ================================================
0134
0135 See also: /sys/class/backlight/<backlight>/ambient_light_zone.
0136
0137 What: /sys/class/backlight/<backlight>/<ambient light zone>_dim
0138 Date: Sep, 2009
0139 KernelVersion: v2.6.32
0140 Contact: device-drivers-devel@blackfin.uclinux.org
0141 Description:
0142 Control the dim brightness for <ambient light zone>
0143 on this <backlight>. Values are between 0 and 127, typically
0144 set to 0. Full off when the backlight is disabled.
0145 This file will also show the dim brightness level stored for
0146 this <ambient light zone>.
0147
0148 The <ambient light zone> is device-driver specific:
0149
0150 For ADP5520 and ADP5501, <ambient light zone> can be:
0151
0152 =========== ================================================
0153 Ambient sysfs entry
0154 light zone
0155 =========== ================================================
0156 daylight /sys/class/backlight/<backlight>/daylight_dim
0157 office /sys/class/backlight/<backlight>/office_dim
0158 dark /sys/class/backlight/<backlight>/dark_dim
0159 =========== ================================================
0160
0161 For ADP8860, <ambient light zone> can be:
0162
0163 =========== ================================================
0164 Ambient sysfs entry
0165 light zone
0166 =========== ================================================
0167 l1_daylight /sys/class/backlight/<backlight>/l1_daylight_dim
0168 l2_office /sys/class/backlight/<backlight>/l2_office_dim
0169 l3_dark /sys/class/backlight/<backlight>/l3_dark_dim
0170 =========== ================================================
0171
0172 For ADP8870, <ambient light zone> can be:
0173
0174 =========== ================================================
0175 Ambient sysfs entry
0176 light zone
0177 =========== ================================================
0178 l1_daylight /sys/class/backlight/<backlight>/l1_daylight_dim
0179 l2_bright /sys/class/backlight/<backlight>/l2_bright_dim
0180 l3_office /sys/class/backlight/<backlight>/l3_office_dim
0181 l4_indoor /sys/class/backlight/<backlight>/l4_indoor_dim
0182 l5_dark /sys/class/backlight/<backlight>/l5_dark_dim
0183 =========== ================================================
0184
0185 See also: /sys/class/backlight/<backlight>/ambient_light_zone.
0186
