RE: [PATCH v1] scsi: ufs: remove clk_scaling_lock when clkscaling isn't supported.

From: Kiwoong Kim
Date: Thu Feb 10 2022 - 21:22:14 EST


> > I think it looks hardware specific.
> > If the feature isn't supported, I think there is no reasonto prevent
> > from
> ^^^
> reason to
>
> > running other functions, such as ufshcd_queuecommand and
> It is no longer used in queuecommand since 5675c381ea51 and 8d077ede48c1

Yeah, you're right. It's just an example. I just want to tell that the lock also protects things that are not related with clk scaling directly.

>
> > ufshcd_exec_dev_cmd, concurrently.
> >
> > So I add a condition at some points protecting with clk_scaling_lock.
> But you still need a way to serialize device management commands.
>
> Thanks,
> Avri

The dev cmd execution period is protected by mutex.
And actual ringing a doorbell is protected by spin lock.

Is there another reason to need clk_scaling_lock even with it?

Thanks.
Kiwoong Kim