[PATCH 2/2] iio: accell: mma8452: add optional vcc regulator operation support

From: Anson Huang
Date: Thu Dec 06 2018 - 01:23:42 EST


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 vcc regulator operation support.

Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
---
drivers/iio/accel/mma8452.c | 88 +++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 86 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 421a0a8..8f6123f 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 +108,7 @@ struct mma8452_data {
u8 data_cfg;
const struct mma_chip_info *chip_info;
int sleep_val;
+ struct regulator *vcc_reg;
};

/**
@@ -1533,6 +1535,14 @@ static int mma8452_probe(struct i2c_client *client,
data->client = client;
mutex_init(&data->lock);
data->chip_info = match->data;
+ data->vcc_reg = devm_regulator_get_optional(&client->dev, "vcc");
+ if (!IS_ERR(data->vcc_reg)) {
+ ret = regulator_enable(data->vcc_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to enable VCC regulator\n");
+ return ret;
+ }
+ }

ret = i2c_smbus_read_byte_data(client, MMA8452_WHO_AM_I);
if (ret < 0)
@@ -1667,6 +1677,8 @@ 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 +1690,14 @@ static int mma8452_remove(struct i2c_client *client)
mma8452_trigger_cleanup(indio_dev);
mma8452_standby(iio_priv(indio_dev));

+ if (!IS_ERR(data->vcc_reg)) {
+ ret = regulator_disable(data->vcc_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to disable VCC regulator\n");
+ return ret;
+ }
+ }
+
return 0;
}

@@ -1696,6 +1716,14 @@ static int mma8452_runtime_suspend(struct device *dev)
return -EAGAIN;
}

+ if (!IS_ERR(data->vcc_reg)) {
+ ret = regulator_disable(data->vcc_reg);
+ if (ret) {
+ dev_err(dev, "failed to disable VCC regulator\n");
+ return ret;
+ }
+ }
+
return 0;
}

@@ -1705,6 +1733,14 @@ static int mma8452_runtime_resume(struct device *dev)
struct mma8452_data *data = iio_priv(indio_dev);
int ret, sleep_val;

+ if (!IS_ERR(data->vcc_reg)) {
+ ret = regulator_enable(data->vcc_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VCC regulator\n");
+ return ret;
+ }
+ }
+
ret = mma8452_active(data);
if (ret < 0)
return ret;
@@ -1723,14 +1759,62 @@ 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->vcc_reg)) {
+ ret = regulator_enable(data->vcc_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VCC regulator\n");
+ return ret;
+ }
+ }
+
+ ret = mma8452_standby(iio_priv(i2c_get_clientdata(
to_i2c_client(dev))));
+ if (ret)
+ return ret;
+
+ if (!IS_ERR(data->vcc_reg)) {
+ ret = regulator_disable(data->vcc_reg);
+ if (ret) {
+ dev_err(dev, "failed to disable VCC 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->vcc_reg)) {
+ ret = regulator_enable(data->vcc_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VCC regulator\n");
+ return ret;
+ }
+ }
+
+ ret = mma8452_active(iio_priv(i2c_get_clientdata(
to_i2c_client(dev))));
+ if (ret)
+ return ret;
+
+ if (!IS_ERR(data->vcc_reg)) {
+ ret = regulator_disable(data->vcc_reg);
+ if (ret) {
+ dev_err(dev, "failed to disable VCC regulator\n");
+ return ret;
+ }
+ }
+
+ return 0;
}
#endif

--
2.7.4