diff mbox series

[v2,01/13] gpiolib: add gpiod_multi_set_value_cansleep()

Message ID 20250206-gpio-set-array-helper-v2-1-1c5f048f79c3@baylibre.com
State New
Headers show
Series gpiolib: add gpiod_multi_set_value_cansleep | expand

Commit Message

David Lechner Feb. 6, 2025, 10:48 p.m. UTC 
Add a new gpiod_multi_set_value_cansleep() helper function with fewer
parameters than gpiod_set_array_value_cansleep().

Calling gpiod_set_array_value_cansleep() can get quite verbose. In many
cases, the first arguments all come from the same struct gpio_descs, so
having a separate function where we can just pass that cuts down on the
boilerplate.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David Lechner <dlechner@baylibre.com>
---
 include/linux/gpio/consumer.h | 7 +++++++
 1 file changed, 7 insertions(+)

Comments

David Lechner Feb. 7, 2025, 4:29 p.m. UTC | #1 
On 2/7/25 3:10 AM, Geert Uytterhoeven wrote:
> Hi David,
> 
> On Thu, 6 Feb 2025 at 23:48, David Lechner <dlechner@baylibre.com> wrote:
>> Add a new gpiod_multi_set_value_cansleep() helper function with fewer
>> parameters than gpiod_set_array_value_cansleep().
>>
>> Calling gpiod_set_array_value_cansleep() can get quite verbose. In many
>> cases, the first arguments all come from the same struct gpio_descs, so
>> having a separate function where we can just pass that cuts down on the
>> boilerplate.
>>
>> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
>> Signed-off-by: David Lechner <dlechner@baylibre.com>
> 
> Thanks for your patch!
> 
>> --- a/include/linux/gpio/consumer.h
>> +++ b/include/linux/gpio/consumer.h
>> @@ -655,4 +655,11 @@ static inline void gpiod_unexport(struct gpio_desc *desc)
>>
>>  #endif /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
>>
>> +static inline int gpiod_multi_set_value_cansleep(struct gpio_descs *descs,
>> +                                                unsigned long *value_bitmap)
>> +{
>> +       return gpiod_set_array_value_cansleep(descs->ndescs, descs->desc,
>> +                                             descs->info, value_bitmap);
> 
> I am wondering whether this needs a check for !IS_ERR_OR_NULL(descs),
> to handle the !CONFIG_GPIOLIB and gpiod_get_array_optional() cases?

I don't think it is strictly needed, but could be convenient for future use
cases. If we add it, should it be:

	if (IS_ERR_OR_NULL(descs))
		return PTR_ERR(descs);

or:

	if (!descs)
		return -EINVAL;

	if (IS_ERR(descs))
		return PTR_ERR(descs);

?

For comparison, gpiod_set_array_value_cansleep() will return -EINVAL if the
first argument is NULL.

> 
> Slightly related: shouldn't gpiod_put_array() (both the implementation
> and the !CONFIG_GPIOLIB dummy) allow the caller to pass NULL, to
> streamline the gpiod_get_array_optional() case?
> 
>> +}
>> +
>>  #endif
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
>
Geert Uytterhoeven Feb. 7, 2025, 4:44 p.m. UTC | #2 
Hi David,

On Fri, 7 Feb 2025 at 17:29, David Lechner <dlechner@baylibre.com> wrote:
> On 2/7/25 3:10 AM, Geert Uytterhoeven wrote:
> > On Thu, 6 Feb 2025 at 23:48, David Lechner <dlechner@baylibre.com> wrote:
> >> Add a new gpiod_multi_set_value_cansleep() helper function with fewer
> >> parameters than gpiod_set_array_value_cansleep().
> >>
> >> Calling gpiod_set_array_value_cansleep() can get quite verbose. In many
> >> cases, the first arguments all come from the same struct gpio_descs, so
> >> having a separate function where we can just pass that cuts down on the
> >> boilerplate.
> >>
> >> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> >> Signed-off-by: David Lechner <dlechner@baylibre.com>
> >
> > Thanks for your patch!
> >
> >> --- a/include/linux/gpio/consumer.h
> >> +++ b/include/linux/gpio/consumer.h
> >> @@ -655,4 +655,11 @@ static inline void gpiod_unexport(struct gpio_desc *desc)
> >>
> >>  #endif /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
> >>
> >> +static inline int gpiod_multi_set_value_cansleep(struct gpio_descs *descs,
> >> +                                                unsigned long *value_bitmap)
> >> +{
> >> +       return gpiod_set_array_value_cansleep(descs->ndescs, descs->desc,
> >> +                                             descs->info, value_bitmap);
> >
> > I am wondering whether this needs a check for !IS_ERR_OR_NULL(descs),
> > to handle the !CONFIG_GPIOLIB and gpiod_get_array_optional() cases?
>
> I don't think it is strictly needed, but could be convenient for future use
> cases. If we add it, should it be:
>
>         if (IS_ERR_OR_NULL(descs))
>                 return PTR_ERR(descs);

return PTR_ERR_OR_ZERO(descs);

(the compiler should optimize away checks common to IS_ERR_OR_NULL()
 and PTR_ERR_OR_ZERO()).

> or:
>
>         if (!descs)
>                 return -EINVAL;
>
>         if (IS_ERR(descs))
>                 return PTR_ERR(descs);
>
> ?

The former.

> For comparison, gpiod_set_array_value_cansleep() will return -EINVAL if the
> first argument is NULL.

That function cannot take an argument returned by a *_optional() call,
if I'm not mistaken.

Gr{oetje,eeting}s,

                        Geert
diff mbox series

Patch

diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index db2dfbae8edbd12059826183b1c0f73c7a58ff40..278a197a9deba11dadbff0b58507df91be658f34 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -655,4 +655,11 @@  static inline void gpiod_unexport(struct gpio_desc *desc)
 
 #endif /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
 
+static inline int gpiod_multi_set_value_cansleep(struct gpio_descs *descs,
+						 unsigned long *value_bitmap)
+{
+	return gpiod_set_array_value_cansleep(descs->ndescs, descs->desc,
+					      descs->info, value_bitmap);
+}
+
 #endif