On Sat, 9 Apr 2022 11:48:49 +0800
Zheyu Ma <zheyuma97@xxxxxxxxx> wrote:
> When the driver fails to enable the regulator 'vid', we will get the
> following splat:
>
> [ 79.955610] WARNING: CPU: 5 PID: 441 at drivers/regulator/core.c:2257 _regulator_put+0x3ec/0x4e0
> [ 79.959641] RIP: 0010:_regulator_put+0x3ec/0x4e0
> [ 79.967570] Call Trace:
> [ 79.967773] <TASK>
> [ 79.967951] regulator_put+0x1f/0x30
> [ 79.968254] devres_release_group+0x319/0x3d0
> [ 79.968608] i2c_device_probe+0x766/0x940
>
> Fix this by disabling the 'vdd' regulator when failing to enable 'vid'
> regulator.
>
> Signed-off-by: Zheyu Ma <zheyuma97@xxxxxxxxx>
This driver doesn't really have a maintainer any more, though Linus W actually
last touched this bit of code. So +CC.
However, it's pretty obviously correct so applied to the fixes-togreg branch of iio.git.
For future reference, please don't send one fix as reply to a fix on a different driver.
Makes a mess of thread handling and tracking in patchwork etc.
Ideally also please provide a fixes tag. For this one I have applied with out it
because it was a long time back and looks like the bug predates a bunch of refactoring
of this code.
Applied to the fixes-togreg branch of iio.git and marked for stable.
Jonathan
> ---
> drivers/iio/magnetometer/ak8975.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 088f748b683e..2432e697150c 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -416,6 +416,7 @@ static int ak8975_power_on(const struct ak8975_data *data)
> if (ret) {
> dev_warn(&data->client->dev,
> "Failed to enable specified Vid supply\n");
> + regulator_disable(data->vdd);
> return ret;
> }
>
