iio: accell: mma8452: add vdd/vddio regulator operation support

The accelerometer's power supply could be controllable on some
platforms, such as i.MX6Q-SABRESD board, the mma8451's power supplies
are controlled by a GPIO fixed regulator, need to make sure the
regulators are enabled before any communication with mma8451, this
patch adds vdd/vddio regulator operation support.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 421a0a8a1379b74dd5847245533b99b9f5a892fa..302781126bc604c635b904b31b069fb6a9f97e3d 100644 (file)
--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -31,6 +31,7 @@
 #include <linux/of_device.h>
 #include <linux/of_irq.h>
 #include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
 
 #define MMA8452_STATUS                         0x00
 #define  MMA8452_STATUS_DRDY                   (BIT(2) | BIT(1) | BIT(0))
@@ -107,6 +108,8 @@ struct mma8452_data {
        u8 data_cfg;
        const struct mma_chip_info *chip_info;
        int sleep_val;
+       struct regulator *vdd_reg;
+       struct regulator *vddio_reg;
 };
 
  /**
@@ -1534,9 +1537,39 @@ static int mma8452_probe(struct i2c_client *client,
        mutex_init(&data->lock);
        data->chip_info = match->data;
 
+       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, MMA8452_WHO_AM_I);
        if (ret < 0)
-               return ret;
+               goto disable_regulators;
 
        switch (ret) {
        case MMA8451_DEVICE_ID:
@@ -1549,7 +1582,8 @@ static int mma8452_probe(struct i2c_client *client,
                        break;
                /* else: fall through */
        default:
-               return -ENODEV;
+               ret = -ENODEV;
+               goto disable_regulators;
        }
 
        dev_info(&client->dev, "registering %s accelerometer; ID 0x%x\n",
@@ -1566,13 +1600,13 @@ static int mma8452_probe(struct i2c_client *client,
 
        ret = mma8452_reset(client);
        if (ret < 0)
-               return ret;
+               goto disable_regulators;
 
        data->data_cfg = MMA8452_DATA_CFG_FS_2G;
        ret = i2c_smbus_write_byte_data(client, MMA8452_DATA_CFG,
                                        data->data_cfg);
        if (ret < 0)
-               return ret;
+               goto disable_regulators;
 
        /*
         * By default set transient threshold to max to avoid events if
@@ -1581,7 +1615,7 @@ static int mma8452_probe(struct i2c_client *client,
        ret = i2c_smbus_write_byte_data(client, MMA8452_TRANSIENT_THS,
                                        MMA8452_TRANSIENT_THS_MASK);
        if (ret < 0)
-               return ret;
+               goto disable_regulators;
 
        if (client->irq) {
                int irq2;
@@ -1595,7 +1629,7 @@ static int mma8452_probe(struct i2c_client *client,
                                                MMA8452_CTRL_REG5,
                                                data->chip_info->all_events);
                        if (ret < 0)
-                               return ret;
+                               goto disable_regulators;
 
                        dev_dbg(&client->dev, "using interrupt line INT1\n");
                }
@@ -1604,11 +1638,11 @@ static int mma8452_probe(struct i2c_client *client,
                                        MMA8452_CTRL_REG4,
                                        data->chip_info->enabled_events);
                if (ret < 0)
-                       return ret;
+                       goto disable_regulators;
 
                ret = mma8452_trigger_setup(indio_dev);
                if (ret < 0)
-                       return ret;
+                       goto disable_regulators;
        }
 
        data->ctrl_reg1 = MMA8452_CTRL_ACTIVE |
@@ -1661,12 +1695,19 @@ buffer_cleanup:
 trigger_cleanup:
        mma8452_trigger_cleanup(indio_dev);
 
+disable_regulators:
+       regulator_disable(data->vddio_reg);
+
+disable_regulator_vdd:
+       regulator_disable(data->vdd_reg);
+
        return ret;
 }
 
 static int mma8452_remove(struct i2c_client *client)
 {
        struct iio_dev *indio_dev = i2c_get_clientdata(client);
+       struct mma8452_data *data = iio_priv(indio_dev);
 
        iio_device_unregister(indio_dev);
 
@@ -1678,6 +1719,9 @@ static int mma8452_remove(struct i2c_client *client)
        mma8452_trigger_cleanup(indio_dev);
        mma8452_standby(iio_priv(indio_dev));
 
+       regulator_disable(data->vddio_reg);
+       regulator_disable(data->vdd_reg);
+
        return 0;
 }
 
@@ -1696,6 +1740,18 @@ static int mma8452_runtime_suspend(struct device *dev)
                return -EAGAIN;
        }
 
+       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;
 }
 
@@ -1705,9 +1761,22 @@ static int mma8452_runtime_resume(struct device *dev)
        struct mma8452_data *data = iio_priv(indio_dev);
        int ret, sleep_val;
 
+       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;
+       }
+
        ret = mma8452_active(data);
        if (ret < 0)
-               return ret;
+               goto runtime_resume_failed;
 
        ret = mma8452_get_odr_index(data);
        sleep_val = 1000 / mma8452_samp_freq[ret][0];
@@ -1717,25 +1786,17 @@ static int mma8452_runtime_resume(struct device *dev)
                msleep_interruptible(sleep_val);
 
        return 0;
-}
-#endif
 
-#ifdef CONFIG_PM_SLEEP
-static int mma8452_suspend(struct device *dev)
-{
-       return mma8452_standby(iio_priv(i2c_get_clientdata(
-               to_i2c_client(dev))));
-}
+runtime_resume_failed:
+       regulator_disable(data->vddio_reg);
+       regulator_disable(data->vdd_reg);
 
-static int mma8452_resume(struct device *dev)
-{
-       return mma8452_active(iio_priv(i2c_get_clientdata(
-               to_i2c_client(dev))));
+       return ret;
 }
 #endif
 
 static const struct dev_pm_ops mma8452_pm_ops = {
-       SET_SYSTEM_SLEEP_PM_OPS(mma8452_suspend, mma8452_resume)
+       SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
        SET_RUNTIME_PM_OPS(mma8452_runtime_suspend,
                           mma8452_runtime_resume, NULL)
 };