[PATCH] gpiolib: Add of_xlate support
Sascha Hauer
sha at pengutronix.de
Mon Aug 8 05:05:05 PDT 2022
On Fri, Aug 05, 2022 at 03:59:28PM +0200, Jules Maselbas wrote:
> The of_xlate callback is used to tanslate a device-tree GPIO specifier
> into a chip relative GPIO number and flags. This callback needs to be
> implemented by GPIO controller driver which doesn't uses the "classic"
> device-tree description, which is:
> gpio = <&gpio-phandle gpio_num gpio_flags>;
>
> But uses something else, like this (but not limited to):
> gpio = <&gpio-phandle gpio_bank gpio_num gpio_flags>;
>
> Currently no GPIO driver require this of_xlate callback, but this will
> be used for sunxi's GPIO support.
>
> Signed-off-by: Jules Maselbas <jmaselbas at kalray.eu>
> ---
> drivers/gpio/gpiolib.c | 60 ++++++++++++++++++++++--------------------
> drivers/of/of_gpio.c | 5 ++--
> include/gpio.h | 3 ++-
> 3 files changed, 37 insertions(+), 31 deletions(-)
Applied, thanks
Sascha
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index f845a57394..97a99b84e3 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -444,44 +444,27 @@ static int of_hog_gpio(struct device_node *np, struct gpio_chip *chip,
> unsigned int idx)
> {
> struct device_node *chip_np = chip->dev->device_node;
> + struct of_phandle_args gpiospec;
> unsigned long flags = 0;
> - u32 gpio_cells, gpio_num, gpio_flags;
> + u32 gpio_flags;
> int ret, gpio;
> const char *name = NULL;
>
> - ret = of_property_read_u32(chip_np, "#gpio-cells", &gpio_cells);
> + ret = of_parse_phandle_with_args(chip_np, "gpios", "#gpio-cells", idx,
> + &gpiospec);
> if (ret)
> return ret;
>
> - /*
> - * Support for GPIOs that don't have #gpio-cells set to 2 is
> - * not implemented
> - */
> - if (WARN_ON(gpio_cells != 2))
> - return -ENOTSUPP;
> -
> - ret = of_property_read_u32_index(np, "gpios", idx * gpio_cells,
> - &gpio_num);
> - if (ret)
> - return ret;
> -
> - ret = of_property_read_u32_index(np, "gpios", idx * gpio_cells + 1,
> - &gpio_flags);
> - if (ret)
> - return ret;
> -
> - if (gpio_flags & OF_GPIO_ACTIVE_LOW)
> - flags |= GPIOF_ACTIVE_LOW;
> -
> - gpio = gpio_get_num(chip->dev, gpio_num);
> + gpio = gpio_of_xlate(chip->dev, &gpiospec, &gpio_flags);
> if (gpio == -EPROBE_DEFER)
> return gpio;
> -
> if (gpio < 0) {
> - dev_err(chip->dev, "unable to get gpio %u\n", gpio_num);
> + dev_err(chip->dev, "unable to get gpio: %d\n", gpio);
> return gpio;
> }
>
> + if (gpio_flags & OF_GPIO_ACTIVE_LOW)
> + flags |= GPIOF_ACTIVE_LOW;
>
> /*
> * Note that, in order to be compatible with Linux, the code
> @@ -636,7 +619,24 @@ void gpiochip_remove(struct gpio_chip *chip)
> list_del(&chip->list);
> }
>
> -int gpio_get_num(struct device_d *dev, int gpio)
> +static int of_gpio_simple_xlate(struct gpio_chip *chip,
> + const struct of_phandle_args *gpiospec,
> + u32 *flags)
> +{
> + /*
> + * Support for GPIOs that don't have #gpio-cells set to 2 is
> + * not implemented
> + */
> + if (WARN_ON(gpiospec->args_count != 2))
> + return -ENOTSUPP;
> +
> + if (flags)
> + *flags = gpiospec->args[1];
> +
> + return chip->base + gpiospec->args[0];
> +}
> +
> +int gpio_of_xlate(struct device_d *dev, struct of_phandle_args *gpiospec, int *flags)
> {
> struct gpio_chip *chip;
>
> @@ -644,8 +644,12 @@ int gpio_get_num(struct device_d *dev, int gpio)
> return -ENODEV;
>
> list_for_each_entry(chip, &chip_list, list) {
> - if (chip->dev == dev)
> - return chip->base + gpio;
> + if (chip->dev != dev)
> + continue;
> + if (chip->ops->of_xlate)
> + return chip->ops->of_xlate(chip, gpiospec, flags);
> + else
> + return of_gpio_simple_xlate(chip, gpiospec, flags);
> }
>
> return -EPROBE_DEFER;
> diff --git a/drivers/of/of_gpio.c b/drivers/of/of_gpio.c
> index 42e0347529..c23923b425 100644
> --- a/drivers/of/of_gpio.c
> +++ b/drivers/of/of_gpio.c
> @@ -62,6 +62,7 @@ int of_get_named_gpio_flags(struct device_node *np, const char *propname,
> {
> struct of_phandle_args out_args;
> struct device_d *dev;
> + int of_flags;
> int ret;
>
> ret = of_parse_phandle_with_args(np, propname, "#gpio-cells",
> @@ -79,7 +80,7 @@ int of_get_named_gpio_flags(struct device_node *np, const char *propname,
> return -EPROBE_DEFER;
> }
>
> - ret = gpio_get_num(dev, out_args.args[0]);
> + ret = gpio_of_xlate(dev, &out_args, &of_flags);
> if (ret == -EPROBE_DEFER)
> return ret;
> if (ret < 0) {
> @@ -89,7 +90,7 @@ int of_get_named_gpio_flags(struct device_node *np, const char *propname,
> }
>
> if (flags) {
> - *flags = out_args.args[1];
> + *flags = of_flags;
> of_gpio_flags_quirks(np, propname, flags, index);
> }
>
> diff --git a/include/gpio.h b/include/gpio.h
> index 6134190138..8218722dcb 100644
> --- a/include/gpio.h
> +++ b/include/gpio.h
> @@ -171,6 +171,7 @@ struct gpio_ops {
> int (*get_direction)(struct gpio_chip *chip, unsigned offset);
> int (*get)(struct gpio_chip *chip, unsigned offset);
> void (*set)(struct gpio_chip *chip, unsigned offset, int value);
> + int (*of_xlate)(struct gpio_chip *chip, const struct of_phandle_args *gpiospec, u32 *flags);
> };
>
> struct gpio_chip {
> @@ -187,7 +188,7 @@ struct gpio_chip {
> int gpiochip_add(struct gpio_chip *chip);
> void gpiochip_remove(struct gpio_chip *chip);
>
> -int gpio_get_num(struct device_d *dev, int gpio);
> +int gpio_of_xlate(struct device_d *dev, struct of_phandle_args *gpiospec, int *flags);
> struct gpio_chip *gpio_get_chip(int gpio);
>
> #endif /* __GPIO_H */
> --
> 2.17.1
>
>
>
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
More information about the barebox
mailing list