Re: [RFC PATCH 1/7] pwm: rename the PWM_POLARITY_INVERSED enum
From: Oleksandr Suvorov
Date: Thu Mar 19 2020 - 09:03:37 EST
On Thu, Mar 19, 2020 at 2:11 PM Uwe Kleine-KÃnig
<u.kleine-koenig@xxxxxxxxxxxxxx> wrote:
>
> Hello,
>
> [dropping Tony Prisk <linux@xxxxxxxxxxxxxxx> from recipients]
>
> On Thu, Mar 19, 2020 at 01:40:28PM +0200, Oleksandr Suvorov wrote:
> > Thierry, I see the PWM core converts the bit field "third cell" into
> > the polarity variable.
> > Now I probably understand your sight and agree that we shouldn't give
> > the same names to bits in bitfield (dts) and values of a variable.
> >
> > But there are lots of useless "0" values of third cell of "pwms"
> > option in dts files.
> >
> > I see 2 ways now:
> > - just remove all "0" "third cell" from "pwms" options in dts files. I
> > see this "0" confuses some people.
>
> Then you have to overwrite pwm-cells of the provider. If there are two
> PWMs used from the same provider and only one is inverted this won't
> work. (Not entirely sure I understood your suggestion.) So I don't like
> this suggestion.
Good point, agree. But we still have the unnamed "0".
What about renaming the dt-bindings macro PWM_POLARITY_INVERTED
and add the new one for the normal polarity?
Like PWM_FLAG_POLARITY_NORMAL / PWM_FLAG_POLARITY_INVERTED or
DT_PWM_POLARITY_NORMAL / DT_PWM_POLARITY_INVERTED?
Using different prefix will prevent interfering names of enum and
macros in the future
and will allow using the named nop-flag PWM_FLAG_POLARITY_NORMAL in dts.
> And also in my eyes this isn't clearer, just more complicated to use.
>
> > - convert pwm_state.polarity into pwm_state.flags and use bitfield
> > directly from dtb.
> > It simplifies the parsing logic and makes adding new flags easier.
>
> *shrug*, I don't care much.
>
> Best regards
> Uwe
>
> --
> Pengutronix e.K. | Uwe Kleine-KÃnig |
> Industrial Linux Solutions | https://www.pengutronix.de/ |
--
Best regards
Oleksandr Suvorov
Toradex AG
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