[PATCH] iio: light: isl29018: add optional vcc regulator operation support

[Anson Huang]

The light sensor's power supply could be controlled 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 optional vcc regulator operation support.

Signed-off-by: Anson Huang <anson.hu...@nxp.com>
---
 drivers/iio/light/isl29018.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/iio/light/isl29018.c b/drivers/iio/light/isl29018.c
index b45400f..47a55c8 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,
@@ -735,6 +737,15 @@ static int isl29018_probe(struct i2c_client *client,
 
        mutex_init(&chip->lock);
 
+       chip->vcc_reg = devm_regulator_get_optional(&client->dev, "vcc");
+       if (!IS_ERR(chip->vcc_reg)) {
+               err = regulator_enable(chip->vcc_reg);
+               if (err) {
+                       dev_err(&client->dev, "failed to enable VDD 
regulator\n");
+                       return err;
+               }
+       }
+
        chip->type = dev_id;
        chip->calibscale = 1;
        chip->ucalibscale = 0;
@@ -768,6 +779,7 @@ 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 +789,14 @@ static int isl29018_suspend(struct device *dev)
         * So we do not have much to do here.
         */
        chip->suspended = true;
+       if (!IS_ERR(chip->vcc_reg)) {
+               ret = regulator_disable(chip->vcc_reg);
+               if (ret) {
+                       dev_err(dev, "failed to disable VDD regulator\n");
+                       mutex_unlock(&chip->lock);
+                       return ret;
+               }
+       }
 
        mutex_unlock(&chip->lock);
 
@@ -790,6 +810,15 @@ static int isl29018_resume(struct device *dev)
 
        mutex_lock(&chip->lock);
 
+       if (!IS_ERR(chip->vcc_reg)) {
+               err = regulator_enable(chip->vcc_reg);
+               if (err) {
+                       dev_err(dev, "failed to enable VDD regulator\n");
+                       mutex_unlock(&chip->lock);
+                       return err;
+               }
+       }
+
        err = isl29018_chip_init(chip);
        if (!err)
                chip->suspended = false;
-- 
2.7.4