[PATCH V2 1/2] dt-bindings: iio: accel: mma8452: add optional power supply property

[PATCH V2 1/2] dt-bindings: iio: accel: mma8452: add optional power supply property

[Anson Huang]

The accelerometer's power supply could be controlled by regulator
on some platforms, add optional property "vdd/vddio" power supply
to let device tree to pass phandles to the regulators to driver.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
 Documentation/devicetree/bindings/iio/accel/mma8452.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/accel/mma8452.txt b/Documentation/devicetree/bindings/iio/accel/mma8452.txt
index 2100e9a..e132394 100644
--- a/Documentation/devicetree/bindings/iio/accel/mma8452.txt
+++ b/Documentation/devicetree/bindings/iio/accel/mma8452.txt
@@ -20,6 +20,10 @@ Optional properties:
   - interrupt-names: should contain "INT1" and/or "INT2", the accelerometer's
 		     interrupt line in use.
 
+  - vdd-supply: phandle to the regulator that provides vdd power to the accelerometer.
+
+  - vddio-supply: phandle to the regulator that provides vddio power to the accelerometer.
+
 Example:
 
 	mma8453fc@1d {
-- 
2.7.4

[PATCH V2 2/2] iio: accell: mma8452: add optional vdd/vddio regulator operation support

[Anson Huang]

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

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
ChangeLog since V1:
    - Add defer_probe check if the return value from devm_regulator_get_optional is ERR_PTR(-EPROBE_DEFER);
    - Replace the "vcc" with "vdd" according to datasheet, and add optional "vddio" supply as well since
      mma8452 also has a vddio supply.
---
 drivers/iio/accel/mma8452.c | 151 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 149 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 421a0a8..18dcf33 100644
--- 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;
 };
 
  /**
@@ -1533,6 +1536,27 @@ static int mma8452_probe(struct i2c_client *client,
 	data->client = client;
 	mutex_init(&data->lock);
 	data->chip_info = match->data;
+	data->vdd_reg = devm_regulator_get_optional(&client->dev, "vdd");
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_enable(data->vdd_reg);
+		if (ret) {
+			dev_err(&client->dev, "failed to enable VDD regulator\n");
+			return ret;
+		}
+	} else if (data->vdd_reg == ERR_PTR(-EPROBE_DEFER)) {
+		return -EPROBE_DEFER;
+	}
+
+	data->vddio_reg = devm_regulator_get_optional(&client->dev, "vddio");
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_enable(data->vddio_reg);
+		if (ret) {
+			dev_err(&client->dev, "failed to enable VDDIO regulator\n");
+			return ret;
+		}
+	} else if (data->vddio_reg == ERR_PTR(-EPROBE_DEFER)) {
+		return -EPROBE_DEFER;
+	}
 
 	ret = i2c_smbus_read_byte_data(client, MMA8452_WHO_AM_I);
 	if (ret < 0)
@@ -1667,6 +1691,8 @@ static int mma8452_probe(struct i2c_client *client,
 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);
+	int ret;
 
 	iio_device_unregister(indio_dev);
 
@@ -1678,6 +1704,21 @@ static int mma8452_remove(struct i2c_client *client)
 	mma8452_trigger_cleanup(indio_dev);
 	mma8452_standby(iio_priv(indio_dev));
 
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_disable(data->vdd_reg);
+		if (ret) {
+			dev_err(&client->dev, "failed to disable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_disable(data->vddio_reg);
+		if (ret) {
+			dev_err(&client->dev, "failed to disable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
 	return 0;
 }
 
@@ -1696,6 +1737,21 @@ static int mma8452_runtime_suspend(struct device *dev)
 		return -EAGAIN;
 	}
 
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_disable(data->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_disable(data->vddio_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
 	return 0;
 }
 
@@ -1705,6 +1761,21 @@ static int mma8452_runtime_resume(struct device *dev)
 	struct mma8452_data *data = iio_priv(indio_dev);
 	int ret, sleep_val;
 
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_enable(data->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to enable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_enable(data->vddio_reg);
+		if (ret) {
+			dev_err(dev, "failed to enable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
 	ret = mma8452_active(data);
 	if (ret < 0)
 		return ret;
@@ -1723,14 +1794,90 @@ static int mma8452_runtime_resume(struct device *dev)
 #ifdef CONFIG_PM_SLEEP
 static int mma8452_suspend(struct device *dev)
 {
-	return mma8452_standby(iio_priv(i2c_get_clientdata(
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_enable(data->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to enable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_enable(data->vddio_reg);
+		if (ret) {
+			dev_err(dev, "failed to enable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
+	ret = mma8452_standby(iio_priv(i2c_get_clientdata(
 		to_i2c_client(dev))));
+	if (ret)
+		return ret;
+
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_disable(data->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_disable(data->vddio_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
+	return 0;
 }
 
 static int mma8452_resume(struct device *dev)
 {
-	return mma8452_active(iio_priv(i2c_get_clientdata(
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_enable(data->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to enable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_enable(data->vddio_reg);
+		if (ret) {
+			dev_err(dev, "failed to enable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
+	ret = mma8452_active(iio_priv(i2c_get_clientdata(
 		to_i2c_client(dev))));
+	if (ret)
+		return ret;
+
+	if (!IS_ERR(data->vdd_reg)) {
+		ret = regulator_disable(data->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDD regulator\n");
+			return ret;
+		}
+	}
+	if (!IS_ERR(data->vddio_reg)) {
+		ret = regulator_disable(data->vddio_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDDIO regulator\n");
+			return ret;
+		}
+	}
+
+	return 0;
 }
 #endif
 
-- 
2.7.4

Re: [PATCH V2 2/2] iio: accell: mma8452: add optional vdd/vddio regulator operation support

[Martin Kepplinger]

On 10.12.18 08:25, Anson Huang wrote:
> The accelerometer's power supply could be controlled by regulator
> on some platforms, such as i.MX6Q-SABRESD board, the mma8451's
> power supply is controlled by a GPIO fixed regulator, need to make
> sure the regulator is enabled before any communication with mma8451,
> this patch adds optional vdd/vddio regulator operation support.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

Acked-by: Martin Kepplinger <martink@posteo.de>

Re: [PATCH V2 2/2] iio: accell: mma8452: add optional vdd/vddio regulator operation support

[Fabio Estevam]

On Mon, Dec 10, 2018 at 5:25 AM Anson Huang <anson.huang@nxp.com> wrote:

> @@ -1533,6 +1536,27 @@ static int mma8452_probe(struct i2c_client *client,
>         data->client = client;
>         mutex_init(&data->lock);
>         data->chip_info = match->data;
> +       data->vdd_reg = devm_regulator_get_optional(&client->dev, "vdd");
> +       if (!IS_ERR(data->vdd_reg)) {
> +               ret = regulator_enable(data->vdd_reg);
> +               if (ret) {
> +                       dev_err(&client->dev, "failed to enable VDD regulator\n");
> +                       return ret;
> +               }
> +       } else if (data->vdd_reg == ERR_PTR(-EPROBE_DEFER)) {
> +               return -EPROBE_DEFER;
> +       }
> +
> +       data->vddio_reg = devm_regulator_get_optional(&client->dev, "vddio");
> +       if (!IS_ERR(data->vddio_reg)) {
> +               ret = regulator_enable(data->vddio_reg);
> +               if (ret) {
> +                       dev_err(&client->dev, "failed to enable VDDIO regulator\n");
> +                       return ret;

As mentioned in your other patch: you should disable the previously
enabled regulator in the error path.