On Thu, 6 Dec 2018 06:23:33 +0000
Anson Huang <anson.hu...@nxp.com> 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 vcc regulator operation support.
>
> Signed-off-by: Anson Huang <anson.hu...@nxp.com>
> ---
> 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)) {
Make sure it's the 'right' error to indicate there isn't a regulator
rather than a deferred response for example.
> + 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
>
