Re: [PATCH 2/2] pinctrl: pinctrl-npcm7xx: Set BGPIOF_VOLATILE_REG

[Kun Yi <kunyi@xxxxxxxxxx>]

On Tue, Oct 30, 2018 at 5:08 AM Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
>
> On Wed, Oct 17, 2018 at 11:30 PM Kun Yi <kunyi@xxxxxxxxxx> wrote:
>
> > Indicate that the pins are both controlled by the pinctrl driver and the
> > generic GPIO driver, thus GPIO driver should read the register value
> > before updating, instead of using the stored shadow register values.
> >
> > Signed-off-by: Kun Yi <kunyi@xxxxxxxxxx>
>
> This is quite a rough measure, if we instead use regmap-mmio
> we can exercise fine control over what register are volatile and
> not instead of saying that all of them or some of them are.

Thanks for your review Linus! I don't have time to rewrite using
regmap-mmio at the moment though. I have discussed with the driver
author and we will first patch the pinctrl driver by making the
pinctrl functions use the gpio-mmio accessors instead of directly reg
read/writes. When I have time I will look into your suggestion to
improve the driver.

>
> Yours,
> Linus Walleij

-- 
Regards,
Kun