2022-07-03 11:12:50

by Aidan MacDonald

[permalink] [raw]
Subject: [PATCH 2/3] gpio: regmap: Support combined GPIO and pin control drivers

Allow gpio-regmap to be used for the GPIO portion of a combined
pin control and GPIO driver by setting the has_pinctrl flag. This
flag will cause GPIO direction set ops to be implemented as calls
to pinctrl_gpio_direction_input/output() instead of updating the
direction set registers directly.

Note that reg_dir_out/in_base is still required for implementing
the GPIO chip's ->get_direction() callback.

Signed-off-by: Aidan MacDonald <[email protected]>
---
drivers/gpio/gpio-regmap.c | 20 ++++++++++++++++++++
include/linux/gpio/regmap.h | 6 ++++++
2 files changed, 26 insertions(+)

diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
index 9256b922c654..4bc01329fb14 100644
--- a/drivers/gpio/gpio-regmap.c
+++ b/drivers/gpio/gpio-regmap.c
@@ -24,6 +24,8 @@ struct gpio_regmap {
unsigned int reg_dir_in_base;
unsigned int reg_dir_out_base;

+ unsigned int has_pinctrl:1;
+
int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
unsigned int offset, unsigned int *reg,
unsigned int *mask);
@@ -170,14 +172,24 @@ static int gpio_regmap_set_direction(struct gpio_chip *chip,
static int gpio_regmap_direction_input(struct gpio_chip *chip,
unsigned int offset)
{
+ struct gpio_regmap *gpio = gpiochip_get_data(chip);
+
+ if (gpio->has_pinctrl)
+ return pinctrl_gpio_direction_input(chip->base + offset);
+
return gpio_regmap_set_direction(chip, offset, false);
}

static int gpio_regmap_direction_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
+ struct gpio_regmap *gpio = gpiochip_get_data(chip);
+
gpio_regmap_set(chip, offset, value);

+ if (gpio->has_pinctrl)
+ return pinctrl_gpio_direction_output(chip->base + offset);
+
return gpio_regmap_set_direction(chip, offset, true);
}

@@ -218,6 +230,14 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
if (config->reg_dir_out_base && config->reg_dir_in_base)
return ERR_PTR(-EINVAL);

+ /*
+ * we need a direction register for implementing ->get_direction
+ * even if ->direction_input/output is handled by pin control
+ */
+ if (config->has_pinctrl && !(config->reg_dir_in_base ||
+ config->reg_dir_out_base))
+ return ERR_PTR(-EINVAL);
+
/* only one of these should be provided */
if (config->reg_field_xlate && config->reg_mask_xlate)
return ERR_PTR(-EINVAL);
diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
index a673dbfe88a3..47acea8cca32 100644
--- a/include/linux/gpio/regmap.h
+++ b/include/linux/gpio/regmap.h
@@ -33,6 +33,10 @@ struct regmap;
* @ngpio_per_reg: Number of GPIOs per register
* @irq_domain: (Optional) IRQ domain if the controller is
* interrupt-capable
+ * @has_pinctrl: If set, the GPIO chip is part of a combined pin control
+ * and GPIO driver; use pinctrl_gpio_direction_input() and
+ * pinctrl_gpio_direction_output() to implement direction
+ * set operations.
* @reg_mask_xlate: (Optional) Translates base address and GPIO
* offset to a register/bitmask pair. If not
* given the default gpio_regmap_simple_xlate()
@@ -88,6 +92,8 @@ struct gpio_regmap_config {
int ngpio_per_reg;
struct irq_domain *irq_domain;

+ unsigned int has_pinctrl:1;
+
int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
unsigned int offset, unsigned int *reg,
unsigned int *mask);
--
2.35.1


2022-07-03 14:29:02

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH 2/3] gpio: regmap: Support combined GPIO and pin control drivers

On Sun, Jul 3, 2022 at 1:11 PM Aidan MacDonald
<[email protected]> wrote:
>
> Allow gpio-regmap to be used for the GPIO portion of a combined
> pin control and GPIO driver by setting the has_pinctrl flag. This
> flag will cause GPIO direction set ops to be implemented as calls
> to pinctrl_gpio_direction_input/output() instead of updating the
> direction set registers directly.
>
> Note that reg_dir_out/in_base is still required for implementing
> the GPIO chip's ->get_direction() callback.

...

> + /*
> + * we need a direction register for implementing ->get_direction
> + * even if ->direction_input/output is handled by pin control
> + */

/*
* Multi-line comments go with this format
* or style. Pay attention to the capitalization
* and English grammar, e.g. period at the end of sentence(s).
*/

...

> + if (config->has_pinctrl && !(config->reg_dir_in_base ||
> + config->reg_dir_out_base))

Can you re-indent this either to be one line or put the second part of
the conditional onto the second line?

And why not use && everywhere?

> + return ERR_PTR(-EINVAL);

--
With Best Regards,
Andy Shevchenko

2022-07-04 15:58:32

by Aidan MacDonald

[permalink] [raw]
Subject: Re: [PATCH 2/3] gpio: regmap: Support combined GPIO and pin control drivers


Andy Shevchenko <[email protected]> writes:

> On Sun, Jul 3, 2022 at 1:11 PM Aidan MacDonald
> <[email protected]> wrote:
>>
>> Allow gpio-regmap to be used for the GPIO portion of a combined
>> pin control and GPIO driver by setting the has_pinctrl flag. This
>> flag will cause GPIO direction set ops to be implemented as calls
>> to pinctrl_gpio_direction_input/output() instead of updating the
>> direction set registers directly.
>>
>> Note that reg_dir_out/in_base is still required for implementing
>> the GPIO chip's ->get_direction() callback.
>
> ...
>
>> + /*
>> + * we need a direction register for implementing ->get_direction
>> + * even if ->direction_input/output is handled by pin control
>> + */
>
> /*
> * Multi-line comments go with this format
> * or style. Pay attention to the capitalization
> * and English grammar, e.g. period at the end of sentence(s).
> */
>

I used this "style" to match the surrounding code, but I suppose
I might as well fix the other comments while I'm here.

>> + if (config->has_pinctrl && !(config->reg_dir_in_base ||
>> + config->reg_dir_out_base))
>
> Can you re-indent this either to be one line or put the second part of
> the conditional onto the second line?

Yep.

>
> And why not use && everywhere?
>

No reason to be honest, but maybe it's easier to understand?

"has pin control and doesn't set reg_dir_in_base or reg_dir_out_base".

Using && is more like this:

"has pin control, doesn't set reg_dir_in_base, and doesn't
set reg_dir_out_base".