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

Andy Shevchenko
2019-12-02T12:51:52Z

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