Re: [PATCH 6/6] platform/x86: int3472/discrete: Get the polarity from the _DSM entry

[Andy Shevchenko <andy.shevchenko@gmail.com>]

On Wed, Nov 30, 2022 at 11:39:42AM +0100, Hans de Goede wrote:
> On 11/30/22 11:01, Andy Shevchenko wrote:
> > On Wed, Nov 30, 2022 at 1:12 AM Hans de Goede <hdegoede@redhat.com> wrote:
> >>
> >> According to:
> >> https://github.com/intel/ipu6-drivers/blob/master/patch/int3472-support-independent-clock-and-LED-gpios-5.17%2B.patch
> >>
> >> Bits 31-24 of the _DSM pin entry integer value codes the active-value,
> >> that is the actual physical signal (0 or 1) which needs to be output on
> >> the pin to turn the sensor chip on (to make it active).
> >>
> >> So if bits 31-24 are 0 for a reset pin, then the actual value of the reset
> >> pin needs to be 0 to take the chip out of reset. IOW in this case the reset
> >> signal is active-high rather then the default active-low.
> >>
> >> And if bits 31-24 are 0 for a clk-en pin then the actual value of the clk
> >> pin needs to be 0 to enable the clk. So in this case the clk-en signal
> >> is active-low rather then the default active-high.
> >>
> >> IOW if bits 31-24 are 0 for a pin, then the default polarity of the pin
> >> is inverted.
> >>
> >> Add a check for this and also propagate this new polarity to the clock
> >> registration.
> > 
> > I like it in this form, thanks!
> > 
> > ...
> > 
> >> +               (polarity == GPIO_ACTIVE_HIGH) ? "high" : "low");
> > 
> > Perhaps
> > 
> > static inline str_high_low(bool v)
> > {
> >   return v ? "high" : "low";
> > }
> > 
> > In the string_helpers.h? If you are okay with the idea, you may use my
> > tag ahead for that patch.
> 
> That is an interesting idea. but IMHO best done in a follow-up series
> after checking for similar code in the rest of the kernel.
> 
> This is based on the assumption that "selling" this new helper to
> the string_helpers.h maintainer will be easier if there are multiple
> consumers of it right away.

strings_helper.h maintainer is any known kernel subsystem maintainer + me
(as a reviewer / main contributor to that library). That's why I proposed
the solution and my tag would be enough to route it via your tree.

So, offer still stays.

-- 
With Best Regards,
Andy Shevchenko