Hi All, I've been contacted by Christopher Williamson who owns this device: https://www.indiegogo.com/projects/gpd-pocket-7-0-umpc-laptop-ubuntu-or-win-10-os-laptop--2#/ And is trying to run Linux on it. As the indiegogo campaign shows is quite a popular device, so supporting this properly with the mainline kernel is important IMHO. It has a (small) fan for cooling which we (Christopher and me) have managed to figure out is controller by 2 GPIOs, giving it 4 speeds (including "off" as speed). Writing a driver for this is easy, it has an ACPI node with a unique _HID and a _CSR table listing the GPIOs. At least writing a driver using the lm_sensors to export this as a fan-speed controller (fake pwm) is easy, but that requires the user to setup the fancontrol service to actually control the fan speed, while as I really want something which will make installing the distributions coming out April 2018 just work without needing tweaks. So I was wondering if there was a way to make the driver directly adjust the fan speeds based on SoC temperature. I was thinking of maybe registering it as a cooling device, if I were to do this will it get called when the system is getting somewhat hot, or only when approaching really hot ? Or maybe a combination of lm_sensors interface, defaulting to medium speed + a cooling device to ramp up to max speed when necessary? Down side of that approach is the fan will spin needlessly when the system is idle ... Any other suggestions ? Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
