[U-Boot] [PATCH 2/3] dm: gpio: Add methods for open drain setting

[Simon Glass]

Hi Mario,

On 26 April 2016 at 08:08, Mario Six <mario.six at gdsys.cc> wrote:
> Signed-off-by: Mario Six <mario.six at gdsys.cc>

Please always add a commit message.

> ---
>  drivers/gpio/gpio-uclass.c | 30 ++++++++++++++++++++++++++++++
>  include/asm-generic/gpio.h | 29 +++++++++++++++++++++++++++++
>  2 files changed, 59 insertions(+)
>
> diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c
> index b58d4e6..16b9648 100644
> --- a/drivers/gpio/gpio-uclass.c
> +++ b/drivers/gpio/gpio-uclass.c
> @@ -352,6 +352,36 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value)
>         return 0;
>  }
>
> +int dm_gpio_get_open_drain(struct gpio_desc *desc)
> +{
> +       struct dm_gpio_ops *ops = gpio_get_ops(desc->dev);
> +       int ret;
> +
> +       ret = check_reserved(desc, "get_open_drain");
> +       if (ret)
> +               return ret;
> +
> +       if (ops->set_open_drain)
> +               return ops->get_open_drain(desc->dev, desc->offset);
> +       else
> +               return 0;

-ENOSYS seems better here

> +}
> +
> +int dm_gpio_set_open_drain(struct gpio_desc *desc, int value)
> +{
> +       struct dm_gpio_ops *ops = gpio_get_ops(desc->dev);
> +       int ret;
> +
> +       ret = check_reserved(desc, "set_open_drain");
> +       if (ret)
> +               return ret;
> +
> +       if (ops->set_open_drain)
> +               ops->set_open_drain(desc->dev, desc->offset, value);

Check return value

> +
> +       return 0;

-ENOSYS here I think, or are you trying to suppress it?

> +}
> +
>  int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags)
>  {
>         struct udevice *dev = desc->dev;
> diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
> index 68b5f0b..ba65080 100644
> --- a/include/asm-generic/gpio.h
> +++ b/include/asm-generic/gpio.h
> @@ -241,6 +241,8 @@ struct dm_gpio_ops {
>                                 int value);
>         int (*get_value)(struct udevice *dev, unsigned offset);
>         int (*set_value)(struct udevice *dev, unsigned offset, int value);
> +       int (*get_open_drain)(struct udevice *dev, unsigned offset);
> +       int (*set_open_drain)(struct udevice *dev, unsigned offset, int value);
>         /**
>          * get_function() Get the GPIO function
>          *
> @@ -541,6 +543,33 @@ int dm_gpio_get_value(const struct gpio_desc *desc);
>  int dm_gpio_set_value(const struct gpio_desc *desc, int value);
>
>  /**
> + * dm_gpio_get_open_drain() - Check if open-drain-mode of a GPIO is active
> + *
> + * This checks if open-drain-mode for a GPIO is enabled or not. This method is
> + * optional; if the driver does not support it, nothing happens when the method
> + * is called.

Can you include a brief description of what open drain is?

> + *
> + * @desc:      GPIO description containing device, offset and flags,
> + *             previously returned by gpio_request_by_name()
> + * @return Value of open drain mode for GPIO (0 for inactive, 1 for active) or
> + *        -ve on error
> + */
> +int dm_gpio_get_open_drain(struct gpio_desc *desc);
> +
> +/**
> + * dm_gpio_set_open_drain() - Switch open-drain-mode of a GPIO on or off
> + *
> + * This enables or disables open-drain-mode for a GPIO. This method is
> + * optional; if the driver does not support it, nothing happens when the method
> + * is called.
> + *
> + * @desc:      GPIO description containing device, offset and flags,
> + *             previously returned by gpio_request_by_name()
> + * @return 0 if OK, -ve on error
> + */
> +int dm_gpio_set_open_drain(struct gpio_desc *desc, int value);
> +
> +/**
>   * dm_gpio_set_dir() - Set the direction for a GPIO
>   *
>   * This sets up the direction according tot the provided flags. It will do
> --
> 2.7.0.GIT
>

Regards,
Simon