Re: [PATCH v2 08/10] iio: light: veml6030: power off device in probe error paths

From: Jonathan Cameron
Date: Sat Sep 28 2024 - 12:23:03 EST


On Mon, 23 Sep 2024 00:17:56 +0200
Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx> wrote:

> Move devm_add_action_or_reset() with a device shut down action above the
> hardware initialization function to ensure that any error path after
> powering on the device leads to a power off.
>
> The power off action is carried out by setting the VEML6030_ALS_SD bit
> of the VEML6030_REG_ALS_CONF, which is harmless in error paths were the
> device is already off. On the other hand, making use of the registered
> action in all error paths makes them more homogeneous by avoiding
> special action depending on the current power state of the device.
>
> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
As per my very late reply, I'd move the devm_add_action_or_reset()
into the hw_init function so it's closely coupled with the thing
it is undoing rather than with a function that does lots of other
things.

You'll want to pass dev into the init function though so it is
easy to see what device the devm_ call is against.
Don't use the parent of the IIO dev as that's an implementation
detail!

Jonathan
> ---
> drivers/iio/light/veml6030.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/light/veml6030.c b/drivers/iio/light/veml6030.c
> index 861bdf2edd4d..19c69bfad8cb 100644
> --- a/drivers/iio/light/veml6030.c
> +++ b/drivers/iio/light/veml6030.c
> @@ -853,12 +853,12 @@ static int veml6030_probe(struct i2c_client *client)
> indio_dev->info = &veml6030_info_no_irq;
> }
>
> - ret = veml6030_hw_init(indio_dev);
> + ret = devm_add_action_or_reset(&client->dev,
> + veml6030_als_shut_down_action, data);
> if (ret < 0)
> return ret;
>
> - ret = devm_add_action_or_reset(&client->dev,
> - veml6030_als_shut_down_action, data);
> + ret = veml6030_hw_init(indio_dev);
> if (ret < 0)
> return ret;
>
>