Re: [PATCH v6] gpio: pca953x: Add Maxim MAX7313 PWM support

From: Andy Shevchenko
Date: Mon Jun 29 2020 - 15:17:57 EST


On Mon, Jun 29, 2020 at 5:08 PM Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:
> Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote on Sun, 3 May 2020
> 12:54:53 +0200:
>
> > The MAX7313 chip is fully compatible with the PCA9535 on its basic
> > functions but can also manage the intensity on each of its ports with
> > PWM. Each output is independent and may be tuned with 16 values (4
> > bits per output). The period is always 32kHz, only the duty-cycle may
> > be changed. One can use any output as GPIO or PWM.

> Can I have a status on this patch please?
>
> If it was forgotten, I would be good to have it queued now, otherwise,
> may I know the reason?

TWIMC, just my 2 cents about this patch.
I don't like it in this form. On the constructive side I can propose
at least two ways to solve:
a) introduce a PWM as a pin mode; move pca953x to pin control; use
this mode with PWM driver being separated from the pin control;
b) introduce an MFD that provides two parts for this GPIO & PWM.

Personally I would go with a) as I know at least one more pin
controller which will get an advantage of this (and it's definitely
not an MFD).

If GPIO / pin control maintainers consider this okay, I will rest my
case, but see above...

--
With Best Regards,
Andy Shevchenko