1.. SPDX-License-Identifier: GPL-2.0-or-later 2 3Kernel driver gpd-fan 4========================= 5 6Author: 7 - Cryolitia PukNgae <cryolitia@uniontech.com> 8 9Description 10------------ 11 12Handheld devices from Shenzhen GPD Technology Co., Ltd. provide fan readings 13and fan control through their embedded controllers. 14 15Supported devices 16----------------- 17 18Currently the driver supports the following handhelds: 19 20 - GPD Win Mini (7840U) 21 - GPD Win Mini (8840U) 22 - GPD Win Mini (HX370) 23 - GPD Pocket 4 24 - GPD Duo 25 - GPD Win Max 2 (6800U) 26 - GPD Win Max 2 2023 (7840U) 27 - GPD Win Max 2 2024 (8840U) 28 - GPD Win Max 2 2025 (HX370) 29 - GPD Win 4 (6800U) 30 - GPD Win 4 (7840U) 31 32Module parameters 33----------------- 34 35gpd_fan_board 36 Force specific which module quirk should be used. 37 Use it like "gpd_fan_board=wm2". 38 39 - wm2 40 - GPD Win 4 (7840U) 41 - GPD Win Max 2 (6800U) 42 - GPD Win Max 2 2023 (7840U) 43 - GPD Win Max 2 2024 (8840U) 44 - GPD Win Max 2 2025 (HX370) 45 - win4 46 - GPD Win 4 (6800U) 47 - win_mini 48 - GPD Win Mini (7840U) 49 - GPD Win Mini (8840U) 50 - GPD Win Mini (HX370) 51 - GPD Pocket 4 52 - GPD Duo 53 54Sysfs entries 55------------- 56 57The following attributes are supported: 58 59fan1_input 60 Read Only. Reads current fan RPM. 61 62pwm1_enable 63 Read/Write. Enable manual fan control. Write "0" to disable control and run 64 at full speed. Write "1" to set to manual, write "2" to let the EC control 65 decide fan speed. Read this attribute to see current status. 66 67 NB：In consideration of the safety of the device, when setting to manual mode, 68 the pwm speed will be set to the maximum value (255) by default. You can set 69 a different value by writing pwm1 later. 70 71pwm1 72 Read/Write. Read this attribute to see current duty cycle in the range 73 [0-255]. When pwm1_enable is set to "1" (manual) write any value in the 74 range [0-255] to set fan speed. 75 76 NB: Many boards (except listed under wm2 above) don't support reading the 77 current pwm value in auto mode. That will just return EOPNOTSUPP. In manual 78 mode it will always return the real value. 79