Hello Marek,
On Sat, Jun 21, 2025 at 07:19:51PM +0200, Marek Vasut wrote:
> On 6/17/25 4:02 PM, Uwe Kleine-König wrote:
> > > +static void argon_fan_hat_i2c_shutdown(struct i2c_client *i2c)
> > > +{
> > > + argon_fan_hat_write(i2c, 100);
> > > +}
> >
> > Isn't that something that the fan driver should cope for? PWM drivers
> > usually do nothing on shutdown.
>
> It's probably best to force the blower fan to maximum before
> reboot/shutdown. The firmware might not handle the fan and the SoC might get
> very hot before Linux boots again.
This is a IMHO a layer violation though. Yes, this PWM only comes in
combination with a fan. But still, the reason to want to emit a 100%
relative duty is because there is a fan, not because this is a PWM. So
this belongs into the fan part. And "funny" enough pwm-fan also has a
.shutdown callback that disables the fan.
So I'd ask you to address this part in the pwm-fan driver and drop the
shutdown callback here.
Best regards
Uwe
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