Re: [PATCH AUTOSEL 4.19 482/671] iio: tsl2772: Use devm_add_action_or_reset for tsl2772_chip_off

Jonathan Cameron
2020-01-16T18:16:27Z

On Thu, 16 Jan 2020 12:02:00 -0500
Sasha Levin <sashal@kernel.org> wrote:

> From: Chuhong Yuan <hslester96@gmail.com>
>
> [ Upstream commit 338084135aeddb103624a6841972fb8588295cc6 ]
>
> Use devm_add_action_or_reset to call tsl2772_chip_off
> when the device is removed.
> This also fixes the issue that the chip is turned off
> before the device is unregistered.
>
> Not marked for stable as fairly hard to hit the bug and
> this is in the middle of a set making other cleanups
> to the driver. Hence will probably need explicit backporting.

Guess I was wrong and it does go on cleanly. I took a quick
look at current 4.19 driver and looks like it's fine on it's
own.

We need to be careful with this one in general though.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> for 4.19

>
> Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
> Fixes: c06c4d793584 ("staging: iio: tsl2x7x/tsl2772: move out of staging")
> Reviewed-by: Brian Masney <masneyb@onstation.org>
> Tested-by: Brian Masney <masneyb@onstation.org>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
> drivers/iio/light/tsl2772.c | 16 +++++++++++++---
> 1 file changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/light/tsl2772.c b/drivers/iio/light/tsl2772.c
> index df5b2a0da96c..f2e308c6d6d7 100644
> --- a/drivers/iio/light/tsl2772.c
> +++ b/drivers/iio/light/tsl2772.c
> @@ -716,6 +716,13 @@ static int tsl2772_chip_off(struct iio_dev *indio_dev)
> return tsl2772_write_control_reg(chip, 0x00);
> }
>
> +static void tsl2772_chip_off_action(void *data)
> +{
> + struct iio_dev *indio_dev = data;
> +
> + tsl2772_chip_off(indio_dev);
> +}
> +
> /**
> * tsl2772_invoke_change - power cycle the device to implement the user
> * parameters
> @@ -1711,9 +1718,14 @@ static int tsl2772_probe(struct i2c_client *clientp,
> if (ret < 0)
> return ret;
>
> + ret = devm_add_action_or_reset(&clientp->dev,
> + tsl2772_chip_off_action,
> + indio_dev);
> + if (ret < 0)
> + return ret;
> +
> ret = iio_device_register(indio_dev);
> if (ret) {
> - tsl2772_chip_off(indio_dev);
> dev_err(&clientp->dev,
> "%s: iio registration failed\n", __func__);
> return ret;
> @@ -1740,8 +1752,6 @@ static int tsl2772_remove(struct i2c_client *client)
> {
> struct iio_dev *indio_dev = i2c_get_clientdata(client);
>
> - tsl2772_chip_off(indio_dev);
> -
> iio_device_unregister(indio_dev);
>
> return 0;