Re: [RFC PATCH] pinctrl: Add SX150X GPIO Extender Pinctrl Driver

[Linus Walleij]

On Thu, Aug 25, 2016 at 3:11 PM, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:

> Since the I2C sx150x GPIO expander driver uses platform_data to managed
> the pins configurations, rewrite the driver as a pinctrl driver using
> pinconf to get pin configurations from DT.
>
> The pinctrl driver is functionnally as the gpio-only driver equivalent
> and can use DT for pinconf.
>
> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>

Overall I'd say this is a nice rewrite. I'd like the following:

- Include Peter Rosin, Wei Chen, Roland Stigge and Vladimir
  Zapolskiy on subsequent posts
  (Added on To:) ideally I want Tested-by: tags from them
  to verify that it doesn't break their current set-ups
  (does it? Especially LPC32xx)

- We need a migration plan: everything that was selecting
  GPIO_SX150X before should now select this instead.
  Just let the Kconfig entry in the drivers/gpio/Kconfig select
  this new driver?

- Make sure it is a slot-in replacement. Else make sure it
  is.

- Delete the old sx150x driver from drivers/gpio in the same
  patch. I'd hate to maintain them side by side. If I apply this,
  the old one must go out at the same time. Conversely I can
  revert the patch and get the old driver back.

- Strangely I don't see refernces to this driver in any
  device tree. Are people not upstreaming their boards?

Yours,
Linus Walleij