iio: magn: ak8975: add Vid regulator

The AK8975 has two power sources: Vdd (analog voltage supply)
and Vid (digital voltage supply). Optionally also obtain the Vid
supply regulator and enable it.

If an error occurs when enabling one of the regulators: bail out.

Cc: Gregor Boirie <gregor.boirie@parrot.com>
Cc: Richard Leitner <dev@g0hl1n.net>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index def693c..ca69f8d 100644 (file)
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -379,6 +379,7 @@ struct ak8975_data {
        u8                      cntl_cache;
        struct iio_mount_matrix orientation;
        struct regulator        *vdd;
+       struct regulator        *vid;
 };
 
 /* Enable attached power regulator if any. */
@@ -399,6 +400,19 @@ static int ak8975_power_on(struct i2c_client *client)
                         "Failed to enable specified Vdd supply\n");
                return ret;
        }
+
+       data->vid = devm_regulator_get(&client->dev, "vid");
+       if (IS_ERR(data->vid)) {
+               ret = PTR_ERR(data->vid);
+       } else {
+               ret = regulator_enable(data->vid);
+       }
+       if (ret) {
+               dev_warn(&client->dev,
+                        "Failed to enable specified Vid supply\n");
+               return ret;
+       }
+       return 0;
 }
 
 /* Disable attached power regulator if any. */
@@ -407,6 +421,7 @@ static void ak8975_power_off(const struct i2c_client *client)
        const struct iio_dev *indio_dev = i2c_get_clientdata(client);
        const struct ak8975_data *data = iio_priv(indio_dev);
 
+       regulator_disable(data->vid);
        regulator_disable(data->vdd);
 }