Hi, Alexandru.
Em seg., 19 de jul. de 2021 às 04:33, Alexandru Ardelean
<ardeleanalex@xxxxxxxxx> escreveu:
>
> On Sun, Jul 18, 2021 at 11:42 PM Théo Borém Fabris <theobf@xxxxxx> wrote:
> >
> > Add a device managed hook, via devm_add_action_or_reset() and
> > max5821_regulator_disable(), to disable voltage regulator on device
> > detach.
> > Replace iio_device_register() by devm_iio_device_register() and remove
> > the max5821_remove() function used to unregister the device and disable the
> > voltage regulator.
> > Remove i2c_set_clientdata() from the probe function, since
> > i2c_get_clientdata() is not used anymore.
>
> Looks good overall.
> A few comments inline.
>
> >
> > Signed-off-by: Théo Borém Fabris <theobf@xxxxxx>
> > ---
> > drivers/iio/dac/max5821.c | 30 ++++++++++++++++--------------
> > 1 file changed, 16 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/iio/dac/max5821.c b/drivers/iio/dac/max5821.c
> > index bd6e75699a63..44c04ae70b32 100644
> > --- a/drivers/iio/dac/max5821.c
> > +++ b/drivers/iio/dac/max5821.c
> > @@ -294,6 +294,13 @@ static const struct iio_info max5821_info = {
> > .write_raw = max5821_write_raw,
> > };
> >
> > +static void max5821_regulator_disable(void *data)
> > +{
> > + struct regulator *rdata = data;
> > +
> > + regulator_disable(rdata);
>
> This can be simplified a bit:
>
> static void max5821_regulator_disable(void *reg)
> {
> regulator_disable(reg);
> }
>
> I used to do explicit casting, but then I also figured that it's not necessary.
>
Ok.
> > +}
> > +
> > static int max5821_probe(struct i2c_client *client,
> > const struct i2c_device_id *id)
> > {
> > @@ -306,7 +313,6 @@ static int max5821_probe(struct i2c_client *client,
> > if (!indio_dev)
> > return -ENOMEM;
> > data = iio_priv(indio_dev);
> > - i2c_set_clientdata(client, indio_dev);
> > data->client = client;
> > mutex_init(&data->lock);
> >
> > @@ -331,6 +337,14 @@ static int max5821_probe(struct i2c_client *client,
> > goto error_free_reg;
> > }
> >
> > + ret = devm_add_action_or_reset(&client->dev, max5821_regulator_disable,
> > + data->vref_reg);
> > + if (ret) {
> > + dev_err(&client->dev,
> > + "Failed to add action to managed regulator: %d\n", ret);
> > + goto error_disable_reg;
>
> return ret;
>
> devm_add_action_or_reset() should call max5821_regulator_disable() in
> case of error
>
Ok.
> > + }
> > +
> > ret = regulator_get_voltage(data->vref_reg);
> > if (ret < 0) {
> > dev_err(&client->dev,
> > @@ -346,7 +360,7 @@ static int max5821_probe(struct i2c_client *client,
> > indio_dev->modes = INDIO_DIRECT_MODE;
> > indio_dev->info = &max5821_info;
> >
> > - return iio_device_register(indio_dev);
> > + return devm_iio_device_register(&client->dev, indio_dev);
> >
> > error_disable_reg:
>
> This entire goto block should be removed.
> The idea of using only devm_ functions is to not have these goto statements.
>
I thought the action added via devm_add_action (and devres_add) was called only
on driver detach, thus the error_disable_reg label would be necessary
to handle the
possible error on regulator_get_voltage. Could you please clarify for
me when does
a driver detach happen?
Thanks for your reply,
Théo
> > regulator_disable(data->vref_reg);
> > @@ -356,17 +370,6 @@ static int max5821_probe(struct i2c_client *client,
> > return ret;
> > }
> >
> > -static int max5821_remove(struct i2c_client *client)
> > -{
> > - struct iio_dev *indio_dev = i2c_get_clientdata(client);
> > - struct max5821_data *data = iio_priv(indio_dev);
> > -
> > - iio_device_unregister(indio_dev);
> > - regulator_disable(data->vref_reg);
> > -
> > - return 0;
> > -}
> > -
> > static const struct i2c_device_id max5821_id[] = {
> > { "max5821", ID_MAX5821 },
> > { }
> > @@ -386,7 +389,6 @@ static struct i2c_driver max5821_driver = {
> > .pm = &max5821_pm_ops,
> > },
> > .probe = max5821_probe,
> > - .remove = max5821_remove,
> > .id_table = max5821_id,
> > };
> > module_i2c_driver(max5821_driver);
> > --
> > 2.20.1
> >
