[Bug 119211] amdgpu disables fan by default

[bugzilla-daemon at kernel.org]

https://bugzilla.kernel.org/show_bug.cgi?id=119211

Stas Sergeev (stsp2 at yandex.ru) changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Kernel Version|4.5.5                       |6.7.7

--- Comment #18 from Stas Sergeev (stsp2 at yandex.ru) ---
I figured out something very interesting
regarding this bug.

Writing 2 to pwm1_enable causes the
fan to rotate for about 10 seconds.
Note that the old value of pwm1_enable
is also 2, so it doesn't change, but
the mere fact of writing has an effect!

And this is not all!
Now if you periodically READ from pwm1,
then the fan doesn't stop! I can do:
while :; do cat /sys/class/hwmon/hwmon0/pwm1; sleep 1; done
And with this, the fan keeps rotating
forever! But if you stop that script
for something like 10 seconds, then
the fan stops and pwm1 reads always
return 0. You need to start again by
writing 2 to pwm1_enable (even if there
is already 2!), and quickly start reading
from pwm1, and you have your fan finally
rotating. :)
A bit of a hand-written fancontrol script. :)

Alex Deucher can you make any sense
out of that?

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are watching the assignee of the bug.