On Sun, 23 Dec 2018 06:12:30 +0000
Anson Huang <anson.huang@xxxxxxx> wrote:
> The magnetometer's power supplies could be controllable on some platforms,
> such as i.MX6Q-SABRESD board, the mag3110's power supplies are controlled
> by a GPIO fixed regulator, need to make sure the regulators are enabled
> before any communication with mag3110, this patch adds vdd/vddio regulator
> operation support.
>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
Same comment on not combining the error handling. It's simply
harder to read to save a few lines of code.
Otherwise, looks fine, though I would ideally like an ack from
Peter on this as it's his driver. If he's busy though I think this
should be safe enough without.
thanks,
Jonathan
> ---
> ChangeLog since V5:
> Make sure both vdd and vddio regulators are aquired before enabling any one of them.
> ---
> drivers/iio/magnetometer/mag3110.c | 88 ++++++++++++++++++++++++++++++++++----
> 1 file changed, 80 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/iio/magnetometer/mag3110.c b/drivers/iio/magnetometer/mag3110.c
> index f063355..f56a99a 100644
> --- a/drivers/iio/magnetometer/mag3110.c
> +++ b/drivers/iio/magnetometer/mag3110.c
> @@ -20,6 +20,7 @@
> #include <linux/iio/buffer.h>
> #include <linux/iio/triggered_buffer.h>
> #include <linux/delay.h>
> +#include <linux/regulator/consumer.h>
>
> #define MAG3110_STATUS 0x00
> #define MAG3110_OUT_X 0x01 /* MSB first */
> @@ -56,6 +57,8 @@ struct mag3110_data {
> struct mutex lock;
> u8 ctrl_reg1;
> int sleep_val;
> + struct regulator *vdd_reg;
> + struct regulator *vddio_reg;
> };
>
> static int mag3110_request(struct mag3110_data *data)
> @@ -469,17 +472,44 @@ static int mag3110_probe(struct i2c_client *client,
> struct iio_dev *indio_dev;
> int ret;
>
> - ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
> - if (ret < 0)
> - return ret;
> - if (ret != MAG3110_DEVICE_ID)
> - return -ENODEV;
> -
> indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> if (!indio_dev)
> return -ENOMEM;
>
> data = iio_priv(indio_dev);
> +
> + data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
> + data->vddio_reg = devm_regulator_get(&client->dev, "vddio");
> + if (IS_ERR(data->vdd_reg) || IS_ERR(data->vddio_reg)) {
> + if (PTR_ERR(data->vdd_reg) == -EPROBE_DEFER ||
> + PTR_ERR(data->vddio_reg) == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> +
> + dev_err(&client->dev, "failed to get VDD/VDDIO regulator!\n");
> + return IS_ERR(data->vdd_reg) ?
> + PTR_ERR(data->vdd_reg) : 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, MAG3110_WHO_AM_I);
> + if (ret < 0)
> + goto disable_regulators;
> + if (ret != MAG3110_DEVICE_ID) {
> + ret = -ENODEV;
> + goto disable_regulators;
> + }
> +
> data->client = client;
> mutex_init(&data->lock);
>
> @@ -499,7 +529,7 @@ static int mag3110_probe(struct i2c_client *client,
>
> ret = mag3110_change_config(data, MAG3110_CTRL_REG1, data->ctrl_reg1);
> if (ret < 0)
> - return ret;
> + goto disable_regulators;
>
> ret = i2c_smbus_write_byte_data(client, MAG3110_CTRL_REG2,
> MAG3110_CTRL_AUTO_MRST_EN);
> @@ -520,16 +550,24 @@ static int mag3110_probe(struct i2c_client *client,
> iio_triggered_buffer_cleanup(indio_dev);
> standby_on_error:
> mag3110_standby(iio_priv(indio_dev));
> +disable_regulators:
> + regulator_disable(data->vddio_reg);
> +disable_regulator_vdd:
> + regulator_disable(data->vdd_reg);
> +
> return ret;
> }
>
> static int mag3110_remove(struct i2c_client *client)
> {
> struct iio_dev *indio_dev = i2c_get_clientdata(client);
> + struct mag3110_data *data = iio_priv(indio_dev);
>
> iio_device_unregister(indio_dev);
> iio_triggered_buffer_cleanup(indio_dev);
> mag3110_standby(iio_priv(indio_dev));
> + regulator_disable(data->vddio_reg);
> + regulator_disable(data->vdd_reg);
>
> return 0;
> }
> @@ -537,14 +575,48 @@ static int mag3110_remove(struct i2c_client *client)
> #ifdef CONFIG_PM_SLEEP
> static int mag3110_suspend(struct device *dev)
> {
> - return mag3110_standby(iio_priv(i2c_get_clientdata(
> + struct mag3110_data *data = iio_priv(i2c_get_clientdata(
> + to_i2c_client(dev)));
> + int ret;
> +
> + ret = mag3110_standby(iio_priv(i2c_get_clientdata(
> to_i2c_client(dev))));
> + if (ret)
> + return ret;
> +
> + 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;
> }
>
> static int mag3110_resume(struct device *dev)
> {
> struct mag3110_data *data = iio_priv(i2c_get_clientdata(
> to_i2c_client(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;
> + }
>
> return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
> data->ctrl_reg1);
