On Mon, 17 Dec 2018 03:25:17 +0000 Anson Huang <[email protected]> wrote:
> The light sensor's power supply could be controllable by regulator > on some platforms, such as i.MX6Q-SABRESD board, the light sensor > isl29023's power supply is controlled by a GPIO fixed regulator, > need to make sure the regulator is enabled before any operation of > sensor, this patch adds vcc regulator operation support. > > Signed-off-by: Anson Huang <[email protected]> Hi Anson See below. > --- > ChangeLog since V6 > - using devm_regulator_get() instead of devm_regulator_get_optional() > since the regulator is > there anyway, if dtb does NOT specify one, regulator framework will > assign dummy regulator for it; > - Setup devm action for cleaning up regulator resource for error handling. > --- > drivers/iio/light/isl29018.c | 58 > ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 58 insertions(+) > > diff --git a/drivers/iio/light/isl29018.c b/drivers/iio/light/isl29018.c > index b45400f..63f7b9d 100644 > --- a/drivers/iio/light/isl29018.c > +++ b/drivers/iio/light/isl29018.c > @@ -23,6 +23,7 @@ > #include <linux/mutex.h> > #include <linux/delay.h> > #include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > #include <linux/slab.h> > #include <linux/iio/iio.h> > #include <linux/iio/sysfs.h> > @@ -95,6 +96,7 @@ struct isl29018_chip { > struct isl29018_scale scale; > int prox_scheme; > bool suspended; > + struct regulator *vcc_reg; > }; > > static int isl29018_set_integration_time(struct isl29018_chip *chip, > @@ -708,6 +710,17 @@ static const char *isl29018_match_acpi_device(struct > device *dev, int *data) > return dev_name(dev); > } > > +static void isl29018_disable_regulator_action(void *_data) > +{ > + struct isl29018_chip *chip = _data; > + int err; > + > + err = regulator_disable(chip->vcc_reg); > + if (err) > + dev_err(regmap_get_device(chip->regmap), > + "failed to disable VCC regulator!\n"); > +} > + > static int isl29018_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > @@ -742,6 +755,37 @@ static int isl29018_probe(struct i2c_client *client, > chip->scale = isl29018_scales[chip->int_time][0]; > chip->suspended = false; > > + chip->vcc_reg = devm_regulator_get(&client->dev, "vcc"); > + if (IS_ERR(chip->vcc_reg)) { > + err = PTR_ERR(chip->vcc_reg); > + if (err != -EPROBE_DEFER) > + dev_err(&client->dev, "failed to get VCC regulator!\n"); > + return err; > + } > + > + err = regulator_enable(chip->vcc_reg); > + if (err) { > + dev_err(&client->dev, "failed to enable VCC regulator!\n"); > + return err; > + } > + > + chip->regmap = devm_regmap_init_i2c(client, > + isl29018_chip_info_tbl[dev_id].regmap_cfg); > + if (IS_ERR(chip->regmap)) { > + err = PTR_ERR(chip->regmap); > + dev_err(&client->dev, "regmap initialization fails: %d\n", err); > + regulator_disable(chip->vcc_reg); > + return err; > + } > + > + err = devm_add_action(&client->dev, isl29018_disable_regulator_action, > + chip); > + if (err) { I'm a little confused, why not do this before devm_regmap_init_i2c. That way you won't have to disable the regulator in that one error path. Also, devm_add_action_or_reset will call isl29018_disable_regulator_action for you on error. > + isl29018_disable_regulator_action(chip); > + dev_err(&client->dev, "failed to setup regulator cleanup > action!\n"); > + return err; > + } > + > chip->regmap = devm_regmap_init_i2c(client, > isl29018_chip_info_tbl[dev_id].regmap_cfg); > if (IS_ERR(chip->regmap)) { > @@ -768,6 +812,7 @@ static int isl29018_probe(struct i2c_client *client, > static int isl29018_suspend(struct device *dev) > { > struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev)); > + int ret; > > mutex_lock(&chip->lock); > > @@ -777,6 +822,12 @@ static int isl29018_suspend(struct device *dev) > * So we do not have much to do here. > */ > chip->suspended = true; > + ret = regulator_disable(chip->vcc_reg); > + if (ret) { > + dev_err(dev, "failed to disable VCC regulator\n"); > + mutex_unlock(&chip->lock); > + return ret; Given you are about to unlock anyway a common pattern is to not check ret until after the unlock, thus simplifying the code. > + } > > mutex_unlock(&chip->lock); > > @@ -790,6 +841,13 @@ static int isl29018_resume(struct device *dev) > > mutex_lock(&chip->lock); > > + err = regulator_enable(chip->vcc_reg); > + if (err) { > + dev_err(dev, "failed to enable VCC regulator\n"); > + mutex_unlock(&chip->lock); > + return err; > + } > + > err = isl29018_chip_init(chip); > if (!err) > chip->suspended = false;
