1.. SPDX-License-Identifier: GPL-2.0+
2
3
4LG Gram laptop extra features
5=============================
6
7By Matan Ziv-Av <matan@svgalib.org>
8
9
10Hotkeys
11-------
12
13The following FN keys are ignored by the kernel without this driver:
14
15- FN-F1 (LG control panel)   - Generates F15
16- FN-F5 (Touchpad toggle)    - Generates F13
17- FN-F6 (Airplane mode)      - Generates RFKILL
18- FN-F8 (Keyboard backlight) - Generates F16.
19  This key also changes keyboard backlight mode.
20- FN-F9 (Reader mode)        - Generates F14
21
22The rest of the FN keys work without a need for a special driver.
23
24
25Reader mode
26-----------
27
28Writing 0/1 to /sys/devices/platform/lg-laptop/reader_mode disables/enables
29reader mode. In this mode the screen colors change (blue color reduced),
30and the reader mode indicator LED (on F9 key) turns on.
31
32
33FN Lock
34-------
35
36Writing 0/1 to /sys/devices/platform/lg-laptop/fn_lock disables/enables
37FN lock.
38
39
40Battery care limit
41------------------
42
43Writing 80/100 to /sys/devices/platform/lg-laptop/battery_care_limit
44sets the maximum capacity to charge the battery. Limiting the charge
45reduces battery capacity loss over time.
46
47This value is reset to 100 when the kernel boots.
48
49
50Fan mode
51--------
52
53Writing 1/0 to /sys/devices/platform/lg-laptop/fan_mode disables/enables
54the fan silent mode.
55
56
57USB charge
58----------
59
60Writing 0/1 to /sys/devices/platform/lg-laptop/usb_charge disables/enables
61charging another device from the USB port while the device is turned off.
62
63This value is reset to 0 when the kernel boots.
64
65
66LEDs
67~~~~
68
69The are two LED devices supported by the driver:
70
71Keyboard backlight
72------------------
73
74A led device named kbd_led controls the keyboard backlight. There are three
75lighting level: off (0), low (127) and high (255).
76
77The keyboard backlight is also controlled by the key combination FN-F8
78which cycles through those levels.
79
80
81Touchpad indicator LED
82----------------------
83
84On the F5 key. Controlled by led device names tpad_led.
85