Re: [PATCH] gpio: menz127: add support for 16Z034 and 16Z037 GPIO controllers

[Jose Javier Rodriguez Barbarin <dev-josejavier.rodriguez@duagon.com>]

On Wed, Nov 05, 2025 at 09:36:52AM +0100, Bartosz Golaszewski wrote:
> On Fri, Oct 31, 2025 at 11:08 AM Jose Javier Rodriguez Barbarin
> <dev-josejavier.rodriguez@duagon.com> wrote:
> >
> > From 7655a73f3888a5d164d1f287ba1f2989bb2aadd2 Mon Sep 17 00:00:00 2001
> > From: Javier Rodriguez <josejavier.rodriguez@duagon.com>
> > Date: Tue, 28 Oct 2025 17:40:14 +0100
> > Subject: [PATCH] gpio: menz127: add support for 16Z034 and 16Z037 GPIO
> >  controllers
> >
> 
> I don't think you used `git send-email` to send this, did you just
> copy the contents of the generated .patch into the email client?
> 

My bad. This was my first time using alpine mail client instead of using
`git send-email`. Since your answer, I did some local tests and now I know
how to use alpine for submitting patches.

> > The 16Z034 and 16Z037 are 8 bits GPIO controllers that share the
> > same registers and features of the 16Z127 GPIO controller.
> >
> > Reviewed-by: Felipe Fensen Casado <felipe.jensen@duagon.com>
> > Signed-off-by: Javier Rodriguez <josejavier.rodriguez@duagon.com>
> > ---
> >  drivers/gpio/gpio-menz127.c | 36 ++++++++++++++++++++++++++++++++++--
> >  1 file changed, 34 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpio/gpio-menz127.c b/drivers/gpio/gpio-menz127.c
> > index da2bf9381cc4..ec9228f1e631 100644
> > --- a/drivers/gpio/gpio-menz127.c
> > +++ b/drivers/gpio/gpio-menz127.c
> > @@ -24,6 +24,12 @@
> >  #define MEN_Z127_ODER  0x1C
> >  #define GPIO_TO_DBCNT_REG(gpio)        ((gpio * 4) + 0x80)
> >
> > +
> 
> Stray newline.
> 
> > +/* MEN Z127 supported model ids*/
> > +#define MEN_Z127_ID    0x7f
> > +#define MEN_Z034_ID    0x22
> > +#define MEN_Z037_ID    0x25
> > +
> >  #define MEN_Z127_DB_MIN_US     50
> >  /* 16 bit compare register. Each bit represents 50us */
> >  #define MEN_Z127_DB_MAX_US     (0xffff * MEN_Z127_DB_MIN_US)
> > @@ -36,6 +42,25 @@ struct men_z127_gpio {
> >         struct resource *mem;
> >  };
> >
> > +static int men_z127_lookup_gpio_size(struct mcb_device *mdev,
> > +                                    unsigned long *sz)
> > +{
> > +       switch (mdev->id) {
> > +       case MEN_Z127_ID:
> > +               *sz = 4;
> > +               break;
> > +       case MEN_Z034_ID:
> > +       case MEN_Z037_ID:
> > +               *sz = 1;
> > +               break;
> > +       default:
> > +               dev_err(&mdev->dev, "no size found for id %d", mdev->id);
> > +               return -EINVAL;
> 
> You can return dev_err_probe() here, it's only used in probe(). But
> TBH probe() is so small I'd just inline this into it.
>

Thanks for your suggestions. I usually try to implement small functions for
improving the reading, but you are right. I've moved these lines to probe(), 
using dev_err_probe() as well.

> > +       }
> > +
> > +       return 0;
> > +}
> > +
> >  static int men_z127_debounce(struct gpio_chip *gc, unsigned gpio,
> >                              unsigned debounce)
> >  {
> > @@ -140,6 +165,7 @@ static int men_z127_probe(struct mcb_device *mdev,
> >         struct men_z127_gpio *men_z127_gpio;
> >         struct device *dev = &mdev->dev;
> >         int ret;
> > +       unsigned long sz;
> >
> >         men_z127_gpio = devm_kzalloc(dev, sizeof(struct men_z127_gpio),
> >                                      GFP_KERNEL);
> > @@ -163,9 +189,13 @@ static int men_z127_probe(struct mcb_device *mdev,
> >
> >         mcb_set_drvdata(mdev, men_z127_gpio);
> >
> > +       ret = men_z127_lookup_gpio_size(mdev, &sz);
> > +       if (ret)
> > +               return ret;
> > +
> >         config = (struct gpio_generic_chip_config) {
> >                 .dev = &mdev->dev,
> > -               .sz = 4,
> > +               .sz = sz,
> >                 .dat = men_z127_gpio->reg_base + MEN_Z127_PSR,
> >                 .set = men_z127_gpio->reg_base + MEN_Z127_CTRL,
> >                 .dirout = men_z127_gpio->reg_base + MEN_Z127_GPIODR,
> > @@ -186,7 +216,9 @@ static int men_z127_probe(struct mcb_device *mdev,
> >  }
> >
> >  static const struct mcb_device_id men_z127_ids[] = {
> > -       { .device = 0x7f },
> > +       { .device = MEN_Z127_ID },
> > +       { .device = MEN_Z034_ID },
> > +       { .device = MEN_Z037_ID },
> >         { }
> >  };
> >  MODULE_DEVICE_TABLE(mcb, men_z127_ids);
> > --
> > 2.51.0
> 
> Bartosz

Thank you, I will submit v2 with these changes.