Re: [PATCH v3 2/5] gpio: gxp: Add HPE GXP GPIO

From: Andy Shevchenko
Date: Thu Jun 08 2023 - 06:23:25 EST


On Wed, Jun 7, 2023 at 11:45 PM Hawkins, Nick <nick.hawkins@xxxxxxx> wrote:
>
> > It does care about things the average GPIO controller driver needs to
> > repeat. So at least you may try and see how it will look.

...

> Is there any documents available describing how regmap_gpio
> populates the GPIO lines? Does it automatically go through and add lines
> for each successful regmap_read and bits per byte?

Nope, it assumes one bit per register or something different if xlate
callback is defined. This is my understanding. That said, it might be
that this is a limitation which does not allow you to switch to that
library.

...

> static const struct regmap_config gxp_int_regmap_config = {
> .reg_bits = 8,

> .reg_stride = 1,

AFAIU 0 is the same as 1, so this can be dropped.

> .val_bits = 8,
> .readable_reg = gxp_read_write_int_register,
> .writeable_reg = gxp_read_write_int_register,
> .max_register = 0x7f
> .name = "gxp-gpio-pl-int"
> };

--
With Best Regards,
Andy Shevchenko