Re: [PATCH] iio: ad7266: Convert to use GPIO descriptors

["Ardelean, Alexandru" <alexandru.Ardelean@analog.com>]

On Mon, 2019-12-02 at 10:38 +0100, Linus Walleij wrote:
> The AD7266 have no in-tree users making use of the platform
> data mechanism to pass address GPIO lines when not using
> a fixed address, so we can easily convert this to use
> GPIO descriptors instead of the platform data integers
> currently passed.
> 
> Lowercase the labels "ad0".."ad2" as this will make a better
> fit for platform descriptions like device tree that prefer
> lowercase names such as "ad0-gpios" rather than "AD0-gpios".
> 
> Board files and other static users of this device can pass
> the same GPIO descriptors using machine descriptor
> tables if need be.
> 

Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>

> Cc: Alison Schofield <amsfield22@gmail.com>
> Cc: Lars-Peter Clausen <lars@metafoo.de>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/iio/adc/ad7266.c             | 29 ++++++++++++----------------
>  include/linux/platform_data/ad7266.h |  3 ---
>  2 files changed, 12 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad7266.c b/drivers/iio/adc/ad7266.c
> index c31b8eabb894..c8524f098883 100644
> --- a/drivers/iio/adc/ad7266.c
> +++ b/drivers/iio/adc/ad7266.c
> @@ -11,7 +11,7 @@
>  #include <linux/spi/spi.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/err.h>
> -#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/module.h>
>  
>  #include <linux/interrupt.h>
> @@ -34,7 +34,7 @@ struct ad7266_state {
>  	enum ad7266_range	range;
>  	enum ad7266_mode	mode;
>  	bool			fixed_addr;
> -	struct gpio		gpios[3];
> +	struct gpio_desc	*gpios[3];
>  
>  	/*
>  	 * DMA (thus cache coherency maintenance) requires the
> @@ -117,7 +117,7 @@ static void ad7266_select_input(struct ad7266_state
> *st, unsigned int nr)
>  	}
>  
>  	for (i = 0; i < 3; ++i)
> -		gpio_set_value(st->gpios[i].gpio, (bool)(nr & BIT(i)));
> +		gpiod_set_value(st->gpios[i], (bool)(nr & BIT(i)));
>  }
>  
>  static int ad7266_update_scan_mode(struct iio_dev *indio_dev,
> @@ -376,7 +376,7 @@ static void ad7266_init_channels(struct iio_dev
> *indio_dev)
>  }
>  
>  static const char * const ad7266_gpio_labels[] = {
> -	"AD0", "AD1", "AD2",
> +	"ad0", "ad1", "ad2",
>  };
>  
>  static int ad7266_probe(struct spi_device *spi)
> @@ -419,14 +419,14 @@ static int ad7266_probe(struct spi_device *spi)
>  
>  		if (!st->fixed_addr) {
>  			for (i = 0; i < ARRAY_SIZE(st->gpios); ++i) {
> -				st->gpios[i].gpio = pdata->addr_gpios[i];
> -				st->gpios[i].flags = GPIOF_OUT_INIT_LOW;
> -				st->gpios[i].label = ad7266_gpio_labels[i];
> +				st->gpios[i] = devm_gpiod_get(&spi->dev,
> +						      ad7266_gpio_labels[i]
> ,
> +						      GPIOD_OUT_LOW);
> +				if (IS_ERR(st->gpios[i])) {
> +					ret = PTR_ERR(st->gpios[i]);
> +					goto error_disable_reg;
> +				}
>  			}
> -			ret = gpio_request_array(st->gpios,
> -				ARRAY_SIZE(st->gpios));
> -			if (ret)
> -				goto error_disable_reg;
>  		}
>  	} else {
>  		st->fixed_addr = true;
> @@ -465,7 +465,7 @@ static int ad7266_probe(struct spi_device *spi)
>  	ret = iio_triggered_buffer_setup(indio_dev,
> &iio_pollfunc_store_time,
>  		&ad7266_trigger_handler, &iio_triggered_buffer_setup_ops);
>  	if (ret)
> -		goto error_free_gpios;
> +		goto error_disable_reg;
>  
>  	ret = iio_device_register(indio_dev);
>  	if (ret)
> @@ -475,9 +475,6 @@ static int ad7266_probe(struct spi_device *spi)
>  
>  error_buffer_cleanup:
>  	iio_triggered_buffer_cleanup(indio_dev);
> -error_free_gpios:
> -	if (!st->fixed_addr)
> -		gpio_free_array(st->gpios, ARRAY_SIZE(st->gpios));
>  error_disable_reg:
>  	if (!IS_ERR(st->reg))
>  		regulator_disable(st->reg);
> @@ -492,8 +489,6 @@ static int ad7266_remove(struct spi_device *spi)
>  
>  	iio_device_unregister(indio_dev);
>  	iio_triggered_buffer_cleanup(indio_dev);
> -	if (!st->fixed_addr)
> -		gpio_free_array(st->gpios, ARRAY_SIZE(st->gpios));
>  	if (!IS_ERR(st->reg))
>  		regulator_disable(st->reg);
>  
> diff --git a/include/linux/platform_data/ad7266.h
> b/include/linux/platform_data/ad7266.h
> index 7de6c16122df..f0652567afba 100644
> --- a/include/linux/platform_data/ad7266.h
> +++ b/include/linux/platform_data/ad7266.h
> @@ -40,14 +40,11 @@ enum ad7266_mode {
>   * @range: Reference voltage range the device is configured for
>   * @mode: Sample mode the device is configured for
>   * @fixed_addr: Whether the address pins are hard-wired
> - * @addr_gpios: GPIOs used for controlling the address pins, only used
> if
> - *		fixed_addr is set to false.
>   */
>  struct ad7266_platform_data {
>  	enum ad7266_range range;
>  	enum ad7266_mode mode;
>  	bool fixed_addr;
> -	unsigned int addr_gpios[3];
>  };
>  
>  #endif