[PATCH V5 2/2] iio: accell: mma8452: add vdd/vddio regulator operation support

Anson Huang
2018-12-17T05:23:02Z

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>
---
ChangeLog since V4:
- using devm_regulator_get() instead of devm_regulator_get_optional() since the regulator is
there always, if dtb does NOT specify one, regulator framework will assign dummy regulator for it.
---
drivers/iio/accel/mma8452.c | 183 +++++++++++++++++++++++++++++++++++++++++---
1 file changed, 172 insertions(+), 11 deletions(-)

diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 421a0a8..9a52426 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;
};

/**
@@ -1534,9 +1537,37 @@ 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)) {
+ ret = PTR_ERR(data->vdd_reg);
+ if (ret != -EPROBE_DEFER)
+ dev_err(&client->dev, "failed to get VDD regulator!\n");
+ return ret;
+ }
+
+ ret = regulator_enable(data->vdd_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to enable VDD regulator!\n");
+ return ret;
+ }
+
+ data->vddio_reg = devm_regulator_get(&client->dev, "vddio");
+ if (IS_ERR(data->vddio_reg)) {
+ ret = PTR_ERR(data->vddio_reg);
+ if (ret != -EPROBE_DEFER)
+ dev_err(&client->dev, "failed to get VDDIO regulator!\n");
+ goto disable_regulator_vdd;
+ }
+
+ 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 +1580,8 @@ 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 +1598,13 @@ 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 +1613,7 @@ 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 +1627,7 @@ 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 +1636,11 @@ 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 +1693,20 @@ static int mma8452_probe(struct i2c_client *client,
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);
+ int ret;

iio_device_unregister(indio_dev);

@@ -1678,6 +1718,18 @@ static int mma8452_remove(struct i2c_client *client)
mma8452_trigger_cleanup(indio_dev);
mma8452_standby(iio_priv(indio_dev));

+ ret = regulator_disable(data->vddio_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to disable VDDIO regulator\n");
+ return ret;
+ }
+
+ ret = regulator_disable(data->vdd_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to disable VDD regulator\n");
+ return ret;
+ }
+
return 0;
}

@@ -1696,6 +1748,18 @@ 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 +1769,22 @@ 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];
@@ -1717,20 +1794,104 @@ static int mma8452_runtime_resume(struct device *dev)
msleep_interruptible(sleep_val);

return 0;
+
+runtime_resume_failed:
+ regulator_disable(data->vddio_reg);
+ regulator_disable(data->vdd_reg);
+
+ return ret;
}
#endif

#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;
+
+ 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_standby(iio_priv(i2c_get_clientdata(
to_i2c_client(dev))));
+ if (ret)
+ goto suspend_failed;
+
+ 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;
+
+suspend_failed:
+ regulator_disable(data->vddio_reg);
+ regulator_disable(data->vdd_reg);
+
+ return ret;
}

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;
+
+ 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(iio_priv(i2c_get_clientdata(
to_i2c_client(dev))));
+ if (ret)
+ goto resume_failed;
+
+ 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;
+
+resume_failed:
+ regulator_disable(data->vddio_reg);
+ regulator_disable(data->vdd_reg);
+
+ return ret;
}
#endif

--
2.7.4