Re: [PATCH] iio: ak8975: Convert to use GPIO descriptor

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Mon, Dec 02, 2019 at 09:17:30AM +0100, Linus Walleij wrote:
> The end-of-conversion (EOC) GPIO line is better to grab using
> a GPIO descriptor. We drop the pdata for this: clients using board
> files can use machine descriptor tables to pass this GPIO from
> static data.
> 

LGTM,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

One nit below, though.

> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Cc: Stephan Gerhold <stephan@gerhold.net>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/iio/magnetometer/ak8975.c       | 54 +++++++++----------------
>  include/linux/iio/magnetometer/ak8975.h |  2 -
>  2 files changed, 20 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 893bec5a0312..da5d75afb536 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -16,8 +16,7 @@
>  #include <linux/mutex.h>
>  #include <linux/delay.h>
>  #include <linux/bitops.h>
> -#include <linux/gpio.h>
> -#include <linux/of_gpio.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/acpi.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/pm_runtime.h>
> @@ -360,7 +359,7 @@ struct ak8975_data {
>  	struct mutex		lock;
>  	u8			asa[3];
>  	long			raw_to_gauss[3];
> -	int			eoc_gpio;
> +	struct gpio_desc	*eoc_gpiod;
>  	int			eoc_irq;
>  	wait_queue_head_t	data_ready_queue;
>  	unsigned long		flags;
> @@ -498,15 +497,15 @@ static int ak8975_setup_irq(struct ak8975_data *data)
>  	if (client->irq)
>  		irq = client->irq;
>  	else
> -		irq = gpio_to_irq(data->eoc_gpio);
> +		irq = gpiod_to_irq(data->eoc_gpiod);
>  
>  	rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
>  			      IRQF_TRIGGER_RISING | IRQF_ONESHOT,
>  			      dev_name(&client->dev), data);
>  	if (rc < 0) {
>  		dev_err(&client->dev,
> -			"irq %d request failed, (gpio %d): %d\n",
> -			irq, data->eoc_gpio, rc);
> +			"irq %d request failed: %d\n",
> +			irq, rc);

Now it fits one line.

>  		return rc;
>  	}
>  
> @@ -549,7 +548,7 @@ static int ak8975_setup(struct i2c_client *client)
>  		return ret;
>  	}
>  
> -	if (data->eoc_gpio > 0 || client->irq > 0) {
> +	if (data->eoc_gpiod || client->irq > 0) {
>  		ret = ak8975_setup_irq(data);
>  		if (ret < 0) {
>  			dev_err(&client->dev,
> @@ -574,7 +573,7 @@ static int wait_conversion_complete_gpio(struct ak8975_data *data)
>  	/* Wait for the conversion to complete. */
>  	while (timeout_ms) {
>  		msleep(AK8975_CONVERSION_DONE_POLL_TIME);
> -		if (gpio_get_value(data->eoc_gpio))
> +		if (gpiod_get_value(data->eoc_gpiod))
>  			break;
>  		timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME;
>  	}
> @@ -646,7 +645,7 @@ static int ak8975_start_read_axis(struct ak8975_data *data,
>  	/* Wait for the conversion to complete. */
>  	if (data->eoc_irq)
>  		ret = wait_conversion_complete_interrupt(data);
> -	else if (gpio_is_valid(data->eoc_gpio))
> +	else if (data->eoc_gpiod)
>  		ret = wait_conversion_complete_gpio(data);
>  	else
>  		ret = wait_conversion_complete_polled(data);
> @@ -856,36 +855,23 @@ static int ak8975_probe(struct i2c_client *client,
>  {
>  	struct ak8975_data *data;
>  	struct iio_dev *indio_dev;
> -	int eoc_gpio;
> +	struct gpio_desc *eoc_gpiod;
>  	int err;
>  	const char *name = NULL;
>  	enum asahi_compass_chipset chipset = AK_MAX_TYPE;
>  	const struct ak8975_platform_data *pdata =
>  		dev_get_platdata(&client->dev);
>  
> -	/* Grab and set up the supplied GPIO. */
> -	if (pdata)
> -		eoc_gpio = pdata->eoc_gpio;
> -	else if (client->dev.of_node)
> -		eoc_gpio = of_get_gpio(client->dev.of_node, 0);
> -	else
> -		eoc_gpio = -1;
> -
> -	if (eoc_gpio == -EPROBE_DEFER)
> -		return -EPROBE_DEFER;
> -
> -	/* We may not have a GPIO based IRQ to scan, that is fine, we will
> -	   poll if so */
> -	if (gpio_is_valid(eoc_gpio)) {
> -		err = devm_gpio_request_one(&client->dev, eoc_gpio,
> -							GPIOF_IN, "ak_8975");
> -		if (err < 0) {
> -			dev_err(&client->dev,
> -				"failed to request GPIO %d, error %d\n",
> -							eoc_gpio, err);
> -			return err;
> -		}
> -	}
> +	/*
> +	 * Grab and set up the supplied GPIO.
> +	 * We may not have a GPIO based IRQ to scan, that is fine, we will
> +	 * poll if so.
> +	 */
> +	eoc_gpiod = devm_gpiod_get_optional(&client->dev, NULL, GPIOD_IN);
> +	if (IS_ERR(eoc_gpiod))
> +		return PTR_ERR(eoc_gpiod);
> +	if (eoc_gpiod)
> +		gpiod_set_consumer_name(eoc_gpiod, "ak_8975");
>  
>  	/* Register with IIO */
>  	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> @@ -896,7 +882,7 @@ static int ak8975_probe(struct i2c_client *client,
>  	i2c_set_clientdata(client, indio_dev);
>  
>  	data->client = client;
> -	data->eoc_gpio = eoc_gpio;
> +	data->eoc_gpiod = eoc_gpiod;
>  	data->eoc_irq = 0;
>  
>  	if (!pdata) {
> diff --git a/include/linux/iio/magnetometer/ak8975.h b/include/linux/iio/magnetometer/ak8975.h
> index ac9366f807cb..df3697183800 100644
> --- a/include/linux/iio/magnetometer/ak8975.h
> +++ b/include/linux/iio/magnetometer/ak8975.h
> @@ -6,11 +6,9 @@
>  
>  /**
>   * struct ak8975_platform_data - AK8975 magnetometer driver platform data
> - * @eoc_gpio:    data ready event gpio
>   * @orientation: mounting matrix relative to main hardware
>   */
>  struct ak8975_platform_data {
> -	int                     eoc_gpio;
>  	struct iio_mount_matrix orientation;
>  };
>  
> -- 
> 2.23.0
> 

-- 
With Best Regards,
Andy Shevchenko