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