I have a Thinkpad P51 (BIOS version: N1UET74W, EC version: N1UHT26W). This patch works on my computer and I can read both fan speeds through sysfs interface. On 2018-09-26 16:34:19 CEST, Stefan Assmann wrote: > Is there a way to actually control the second fan? There's pwm1, but no > pwm2. And pwm1 only affects fan1. I have played with the driver code and I noticed that it is possible to control both fans independently (unlike what the "Fan subdriver" comment in the code says). You can do that simply by calling fan_select_fan1 or fan_select_fan2, to select a fan to be controlled, before calling fan_set_level. All control parameters (disengaged, manual speeds, auto) are fully independent. What is not smooth is reading back current control parameters from register 0x2f (like fan_pwm1_show or fan_pwm1_enable_show actually do), because the EC ignores which fan is currently selected and it always returns the last written value. Distinti Saluti/Best Regards, Dario Messina
