Re: [PATCH v3 6/7] iio: light: al3320a implement suspend support

Jonathan Cameron
2020-02-02T10:24:28Z

On Sat, 1 Feb 2020 19:00:23 +0100
David Heidelberg <david@ixit.cz> wrote:

> AL3320a is fairly simple chip, so for suspend is enough to disable and
> later enable it again.
>
> Signed-off-by: David Heidelberg <david@ixit.cz>
> ---
> drivers/iio/light/al3320a.c | 31 ++++++++++++++++++++++++++-----
> 1 file changed, 26 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iio/light/al3320a.c b/drivers/iio/light/al3320a.c
> index 613830b7df6e..d99f9d139b5f 100644
> --- a/drivers/iio/light/al3320a.c
> +++ b/drivers/iio/light/al3320a.c
> @@ -7,6 +7,9 @@
> * IIO driver for AL3320A (7-bit I2C slave address 0x1C).
> *
> * TODO: interrupt support, thresholds
> + * When the driver will get support for interrupt handling, then interrupt
> + * will need to be disabled before turning sensor OFF in order to avoid
> + * potential races with the interrupt handling.
> */
>
> #include <linux/module.h>
> @@ -84,13 +87,19 @@ static const struct attribute_group al3320a_attribute_group = {
> .attrs = al3320a_attributes,
> };
>
> +static int al3320a_set_pwr(struct i2c_client *client, bool pwr)
> +{
> + u8 val = pwr ? AL3320A_CONFIG_ENABLE : AL3320A_CONFIG_DISABLE;
> + return i2c_smbus_write_byte_data(data->client, AL3320A_REG_CONFIG, val);
> +}
> +

One blank line is almost always enough.

> +
> static int al3320a_init(struct al3320a_data *data)
> {
> int ret;
>
> - /* power on */
> - ret = i2c_smbus_write_byte_data(data->client, AL3320A_REG_CONFIG,
> - AL3320A_CONFIG_ENABLE);
> + ret = al3320a_set_pwr(data->client, true);
> +
> if (ret < 0)
> return ret;
>
> @@ -208,10 +217,21 @@ static int al3320a_probe(struct i2c_client *client,
>
> static int al3320a_remove(struct i2c_client *client)
> {
> - return i2c_smbus_write_byte_data(client, AL3320A_REG_CONFIG,
> - AL3320A_CONFIG_DISABLE);
> + return al3320a_set_pwr(client, false);
> +}
> +
> +static int __maybe_unused al3320a_suspend(struct device *dev)
> +{
> + return al3320a_set_pwr(to_i2c_client(dev), false);
> +}
> +
> +static int __maybe_unused al3320a_resume(struct device *dev)
> +{
> + return al3320a_set_pwr(to_i2c_client(dev), true);
> }
>
> +SIMPLE_DEV_PM_OPS(al3320a_pm_ops, al3320a_suspend, al3320a_resume);
> +
> static const struct i2c_device_id al3320a_id[] = {
> {"al3320a", 0},
> {}
> @@ -221,6 +241,7 @@ MODULE_DEVICE_TABLE(i2c, al3320a_id);
> static struct i2c_driver al3320a_driver = {
> .driver = {
> .name = AL3320A_DRV_NAME,
> + .pm = &al3320a_pm_ops,
> },
> .probe = al3320a_probe,
> .remove = al3320a_remove,