Hi John, On 1/10/23 14:26, John Martens wrote: > Dear Kernel devs, Mr. Hans de Goede, Mr. Ike Panhc, > > I am currently working on a driver for fan control, fan speed, temperature sensors, and power mode (platform profile) for Lenovo Legion Laptops. Switching iGPU/dGPU could also be possible. It is a port of the closed and open tools in Windows LenovoLegionToolkit, Vantage, LegionFanControl. I am testing it on different laptops with the help of a forum/chat and its working quite good. Thank you for reaching out. I'm currently catching up with quite a big patch/bug backlog after being on holiday for 2 weeks. I'll get back to you on this, but please give me some time. If you have not heard back from me in 2 weeks, feel free to ping me about this. Regards, Hans > > There is a README (https://github.com/johnfanv2/LenovoLegionLinux) and code (https://github.com/johnfanv2/LenovoLegionLinux/blob/main/kernel_module/legion-laptop.c). > > I would be interested to get your opinion. > > Questions > > Should this extend ideapad_laptop.c or a new file? > - pro: > - both access parts of the same hardware > - con: > - both files are already quite large > - it only works on Lenovo Legion laptops that have this > custom control firmware in the embedded controller (EC) > - there is almost no reuse of code > > Which method do you prefer writing to EC memory for older models? With ioremap or outb? > - To use ioremap one needs to get the start address. It is > different on Intel vs AMD. It is the same as a OperationRegion > in the ACPI tables, e.g. "OperationRegion (ERAX, SystemMemory, > 0xFE00D400, 0xFF)". However, I have found no kernel functions > to get the address (here 0xFE00D400) of a OperationRegion. > One could also hardcode it for each model/firmware. > - alternative (which I am currently using) is sending commands > to IO ports 0x4E/0x4F (Super IO controller). > > Background > > The laptops come with an embedded controller (EC) from ITE. These usually come with a 3 point fan curve in ROM, but also can be flashed with a small additional custom program. Lenovo implemented implemented a 10 point fan curve. The program is also shipped with each EFI update. > > The fan curve can be edited by writing to some memory locations in the EC. These locations are > > The driver works by: > - directly writing/reading embedded controller memory > - older models (2020-2021): there are two possibilities > - the EC memory is already memory mapped, so one can > use ioremap > - one can use outb/inb and write sequenc of commands to > port 0x43, 0x4F (super IO ports) > - ideapad_laptop.c writes to some parts of EC memory > with ACPI methods VPCR, VPCW. However, these do not seem > to work in the memory region with the fan curve. > - newer models (2022): these provide ACPI/WMI methods > setFanCurve/getFanCurve to write to these regions. However, I > have implemented that and have no models for testing > > The driver works for the models 2020-2022. The code layout is heavily inspired by the ideapad_laptop driver. > > Best regards, > > John Martens >
