iio: magnetometer: mag3110: add vdd/vddio regulator operation support

The magnetometer's power supplies could be controllable on some platforms,
such as i.MX6Q-SABRESD board, the mag3110's power supplies are controlled
by a GPIO fixed regulator, need to make sure the regulators are enabled
before any communication with mag3110, this patch adds vdd/vddio regulator
operation support.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/magnetometer/mag3110.c b/drivers/iio/magnetometer/mag3110.c
index f063355480bae4e82aebd9e35a1a32d0fffaaa2b..dd990cdb04a8bd09deafff59c7ddad39fe4085c7 100644 (file)
--- a/drivers/iio/magnetometer/mag3110.c
+++ b/drivers/iio/magnetometer/mag3110.c
@@ -20,6 +20,7 @@
 #include <linux/iio/buffer.h>
 #include <linux/iio/triggered_buffer.h>
 #include <linux/delay.h>
+#include <linux/regulator/consumer.h>
 
 #define MAG3110_STATUS 0x00
 #define MAG3110_OUT_X 0x01 /* MSB first */
@@ -56,6 +57,8 @@ struct mag3110_data {
        struct mutex lock;
        u8 ctrl_reg1;
        int sleep_val;
+       struct regulator *vdd_reg;
+       struct regulator *vddio_reg;
 };
 
 static int mag3110_request(struct mag3110_data *data)
@@ -469,17 +472,50 @@ static int mag3110_probe(struct i2c_client *client,
        struct iio_dev *indio_dev;
        int ret;
 
-       ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
-       if (ret < 0)
-               return ret;
-       if (ret != MAG3110_DEVICE_ID)
-               return -ENODEV;
-
        indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
        if (!indio_dev)
                return -ENOMEM;
 
        data = iio_priv(indio_dev);
+
+       data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
+       if (IS_ERR(data->vdd_reg)) {
+               if (PTR_ERR(data->vdd_reg) == -EPROBE_DEFER)
+                       return -EPROBE_DEFER;
+
+               dev_err(&client->dev, "failed to get VDD regulator!\n");
+               return PTR_ERR(data->vdd_reg);
+       }
+
+       data->vddio_reg = devm_regulator_get(&client->dev, "vddio");
+       if (IS_ERR(data->vddio_reg)) {
+               if (PTR_ERR(data->vddio_reg) == -EPROBE_DEFER)
+                       return -EPROBE_DEFER;
+
+               dev_err(&client->dev, "failed to get VDDIO regulator!\n");
+               return PTR_ERR(data->vddio_reg);
+       }
+
+       ret = regulator_enable(data->vdd_reg);
+       if (ret) {
+               dev_err(&client->dev, "failed to enable VDD regulator!\n");
+               return ret;
+       }
+
+       ret = regulator_enable(data->vddio_reg);
+       if (ret) {
+               dev_err(&client->dev, "failed to enable VDDIO regulator!\n");
+               goto disable_regulator_vdd;
+       }
+
+       ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
+       if (ret < 0)
+               goto disable_regulators;
+       if (ret != MAG3110_DEVICE_ID) {
+               ret = -ENODEV;
+               goto disable_regulators;
+       }
+
        data->client = client;
        mutex_init(&data->lock);
 
@@ -499,7 +535,7 @@ static int mag3110_probe(struct i2c_client *client,
 
        ret = mag3110_change_config(data, MAG3110_CTRL_REG1, data->ctrl_reg1);
        if (ret < 0)
-               return ret;
+               goto disable_regulators;
 
        ret = i2c_smbus_write_byte_data(client, MAG3110_CTRL_REG2,
                MAG3110_CTRL_AUTO_MRST_EN);
@@ -520,16 +556,24 @@ buffer_cleanup:
        iio_triggered_buffer_cleanup(indio_dev);
 standby_on_error:
        mag3110_standby(iio_priv(indio_dev));
+disable_regulators:
+       regulator_disable(data->vddio_reg);
+disable_regulator_vdd:
+       regulator_disable(data->vdd_reg);
+
        return ret;
 }
 
 static int mag3110_remove(struct i2c_client *client)
 {
        struct iio_dev *indio_dev = i2c_get_clientdata(client);
+       struct mag3110_data *data = iio_priv(indio_dev);
 
        iio_device_unregister(indio_dev);
        iio_triggered_buffer_cleanup(indio_dev);
        mag3110_standby(iio_priv(indio_dev));
+       regulator_disable(data->vddio_reg);
+       regulator_disable(data->vdd_reg);
 
        return 0;
 }
@@ -537,14 +581,48 @@ static int mag3110_remove(struct i2c_client *client)
 #ifdef CONFIG_PM_SLEEP
 static int mag3110_suspend(struct device *dev)
 {
-       return mag3110_standby(iio_priv(i2c_get_clientdata(
+       struct mag3110_data *data = iio_priv(i2c_get_clientdata(
+               to_i2c_client(dev)));
+       int ret;
+
+       ret = mag3110_standby(iio_priv(i2c_get_clientdata(
                to_i2c_client(dev))));
+       if (ret)
+               return ret;
+
+       ret = regulator_disable(data->vddio_reg);
+       if (ret) {
+               dev_err(dev, "failed to disable VDDIO regulator\n");
+               return ret;
+       }
+
+       ret = regulator_disable(data->vdd_reg);
+       if (ret) {
+               dev_err(dev, "failed to disable VDD regulator\n");
+               return ret;
+       }
+
+       return 0;
 }
 
 static int mag3110_resume(struct device *dev)
 {
        struct mag3110_data *data = iio_priv(i2c_get_clientdata(
                to_i2c_client(dev)));
+       int ret;
+
+       ret = regulator_enable(data->vdd_reg);
+       if (ret) {
+               dev_err(dev, "failed to enable VDD regulator\n");
+               return ret;
+       }
+
+       ret = regulator_enable(data->vddio_reg);
+       if (ret) {
+               dev_err(dev, "failed to enable VDDIO regulator\n");
+               regulator_disable(data->vdd_reg);
+               return ret;
+       }
 
        return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
                data->ctrl_reg1);