Re: [PATCH v2 1/5] gpio: add support to get local gpio number
From: Marco Felsch
Date: Thu Nov 28 2019 - 07:49:52 EST
On 19-11-28 11:46, Bartosz Golaszewski wrote:
> År., 27 lis 2019 o 14:59 Marco Felsch <m.felsch@xxxxxxxxxxxxxx> napisaÅ(a):
> >
> > Sometimes consumers needs to know the gpio-chip local gpio number of a
> > 'struct gpio_desc' for further configuration. This is often the case for
> > mfd devices.
> >
>
> We already have this support. It's just a matter of exporting it, so
> maybe adjust the commit message to not be confusing.
Therefore I mentioned the consumers.
> That being said: I'm not really a fan of this - the whole idea of gpio
> descriptors was to make them opaque and their hardware offsets
> irrelevant. :(
I know therefore I added a driver local helper but this wasn't the way
Linus wanted to go..
> > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > ---
> > drivers/gpio/gpiolib.c | 6 ++++++
> > include/linux/gpio/consumer.h | 10 ++++++++++
> > 2 files changed, 16 insertions(+)
> >
> > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> > index 104ed299d5ea..7709648313fc 100644
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -4377,6 +4377,12 @@ int gpiod_count(struct device *dev, const char *con_id)
> > }
> > EXPORT_SYMBOL_GPL(gpiod_count);
> >
> > +int gpiod_to_offset(struct gpio_desc *desc)
>
> Maybe call it: gpiod_desc_to_offset()?
The function name is proposed by Linus too so Linus what's your
oppinion?
Regards,
Marco
> > +{
> > + return gpio_chip_hwgpio(desc);
> > +}
> > +EXPORT_SYMBOL_GPL(gpiod_to_offset);
> > +
> > /**
> > * gpiod_get - obtain a GPIO for a given GPIO function
> > * @dev: GPIO consumer, can be NULL for system-global GPIOs
> > diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
> > index b70af921c614..e2178c3bf7fd 100644
> > --- a/include/linux/gpio/consumer.h
> > +++ b/include/linux/gpio/consumer.h
> > @@ -60,6 +60,9 @@ enum gpiod_flags {
> > /* Return the number of GPIOs associated with a device / function */
> > int gpiod_count(struct device *dev, const char *con_id);
> >
> > +/* Get the local chip offset from a global desc */
> > +int gpiod_to_offset(struct gpio_desc *desc);
> > +
> > /* Acquire and dispose GPIOs */
> > struct gpio_desc *__must_check gpiod_get(struct device *dev,
> > const char *con_id,
> > @@ -189,6 +192,13 @@ static inline int gpiod_count(struct device *dev, const char *con_id)
> > return 0;
> > }
> >
> > +static inline int gpiod_to_offset(struct gpio_desc *desc)
> > +{
> > + /* GPIO can never have been requested */
> > + WARN_ON(desc);
> > + return 0;
> > +}
> > +
> > static inline struct gpio_desc *__must_check gpiod_get(struct device *dev,
> > const char *con_id,
> > enum gpiod_flags flags)
> > --
> > 2.20.1
> >