Re: [PATCH] iio:dac:max517: Use devm_iio_device_register()

From: Alexandru Ardelean
Date: Sun Mar 14 2021 - 07:09:34 EST


On Sun, Mar 14, 2021 at 11:34 AM Mugilraj Dhavachelvan
<dmugil2000@xxxxxxxxx> wrote:
>
> Use devm_iio_device_register() to avoid remove function and
> drop explicit call to iio_device_unregister().
>
> Signed-off-by: Mugilraj Dhavachelvan <dmugil2000@xxxxxxxxx>
> ---
> drivers/iio/dac/max517.c | 9 +--------
> 1 file changed, 1 insertion(+), 8 deletions(-)
>
> diff --git a/drivers/iio/dac/max517.c b/drivers/iio/dac/max517.c
> index 7e01838ef4d0..5f72f126162d 100644
> --- a/drivers/iio/dac/max517.c
> +++ b/drivers/iio/dac/max517.c
> @@ -189,13 +189,7 @@ static int max517_probe(struct i2c_client *client,
> data->vref_mv[chan] = platform_data->vref_mv[chan];
> }
>
> - return iio_device_register(indio_dev);
> -}
> -

In this case you can also remove the line with
i2c_set_clientdata(client, indio_dev);

A lot of times, when functions like i2c_get_clientdata() get removed,
the i2c_set_clientdata() function becomes useless.
i.e. it stores some data that will never be used in the lifetime of the driver.

It isn't always the case that you can do that; so, some care must be
taken to avoid special cases.
But in this case, you can remove the i2c_set_clientdata() call.


> -static int max517_remove(struct i2c_client *client)
> -{
> - iio_device_unregister(i2c_get_clientdata(client));
> - return 0;
> + return devm_iio_device_register(&client->dev, indio_dev);
> }
>
> static const struct i2c_device_id max517_id[] = {
> @@ -214,7 +208,6 @@ static struct i2c_driver max517_driver = {
> .pm = &max517_pm_ops,
> },
> .probe = max517_probe,
> - .remove = max517_remove,
> .id_table = max517_id,
> };
> module_i2c_driver(max517_driver);
> --
> 2.25.1
>