[PATCH 1/5] gpio: Add the devm_get_index_gpiod_from_child() helper

Boris Brezillon boris.brezillon at free-electrons.com
Mon Jan 30 02:19:54 PST 2017


Hi Linus,

On Mon, 30 Jan 2017 10:49:23 +0100
Linus Walleij <linus.walleij at linaro.org> wrote:

> On Fri, Jan 27, 2017 at 5:34 PM, Boris Brezillon
> <boris.brezillon at free-electrons.com> wrote:
> 
> > devm_get_gpiod_from_child() currently allows GPIO users to request a GPIO
> > that is defined in a child fwnode instead of directly in the device
> > fwnode. Extend this API by adding the devm_get_index_gpiod_from_child()
> > helpers which does the same except you can also specify an index in case
> > the 'xx-gpios' property describe several GPIOs.
> >
> > Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>  
> 
> Cc Russell who faced this problem in the mvebu PCI driver (IIRC).
> 
> (...)
> 
> > +struct gpio_desc *devm_get_index_gpiod_from_child(struct device *dev,
> > +                                                 const char *con_id,
> > +                                                 int index,
> > +                                                 struct fwnode_handle *child)
> >  {
> >         static const char * const suffixes[] = { "gpios", "gpio" };
> >         char prop_name[32]; /* 32 is max size of property name */
> > @@ -154,7 +157,7 @@ struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
> >                         snprintf(prop_name, sizeof(prop_name), "%s",
> >                                                                suffixes[i]);
> >
> > -               desc = fwnode_get_named_gpiod(child, prop_name);
> > +               desc = fwnode_get_named_gpiod(child, prop_name, index);
> >                 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
> >                         break;
> >         }
> > @@ -168,6 +171,23 @@ struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
> >
> >         return desc;
> >  }
> > +EXPORT_SYMBOL(devm_get_index_gpiod_from_child);  
> 
> Rename this devm_fwnode_get_index_gpiod_from_child()
> so that it fits the namespace of the other fwnode functions.

Okay.

> 
> > + * devm_get_gpiod_from_child - get a GPIO descriptor from a device's child node
> > + * @dev:       GPIO consumer
> > + * @con_id:    function within the GPIO consumer
> > + * @child:     firmware node (child of @dev)
> > + *
> > + * GPIO descriptors returned from this function are automatically disposed on
> > + * driver detach.
> > + */
> > +struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
> > +                                           const char *con_id,
> > +                                           struct fwnode_handle *child)
> > +{
> > +       return devm_get_index_gpiod_from_child(dev, con_id, 0, child);
> > +}  
> 
> Take the opportunity to rename this devm_fwnode_get_gpiod_from_child()
> as well.

Sure, I'll provide a separate patch renaming this function.

Thanks,

Boris



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