Re: [PATCH 1/5] iio: light: us5182d: Add property for choosing default power mode

Jonathan Cameron
2015-11-29T14:35:09Z

On 24/11/15 10:59, Adriana Reus wrote:
> This chip supports two power modes.
> 1. "one-shot" mode - the chip activates and executes one complete
> conversion loop and then shuts itself down. This is the default mode
> chosen for raw reads.
> 2. "continuous" mode - the chip takes continuous measurements.
>
> Continuous mode is more expensive power-wise but may be more reliable.
> Add a property so that if preferred, the default power mode for raw
> reads can be set to continuous.
> Separate one-shot enabling in a separate function that will be used
> depending on the chosen power mode. Also create a function for
> powering the chip on and off.
>
> Signed-off-by: Adriana Reus <adriana.reus@intel.com>
A couple of nitpicks inline... I've fixed them up when applying to the
togreg branch of iio.git - initially pushed out as testing for the autobuilders
to play with them.

Thanks,

Jonathan
> ---
> drivers/iio/light/us5182d.c | 90 +++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 78 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/iio/light/us5182d.c b/drivers/iio/light/us5182d.c
> index 49dab3c..7993014 100644
> --- a/drivers/iio/light/us5182d.c
> +++ b/drivers/iio/light/us5182d.c
> @@ -99,6 +99,11 @@ enum mode {
> US5182D_PX_ONLY
> };
>
> +enum pmode {
> + US5182D_CONTINUOUS,
> + US5182D_ONESHOT
> +};
> +
> struct us5182d_data {
> struct i2c_client *client;
> struct mutex lock;
> @@ -112,6 +117,9 @@ struct us5182d_data {
> u16 *us5182d_dark_ths;
>
> u8 opmode;
> + u8 power_mode;
> +
> + bool default_continuous;
> };
>
> static IIO_CONST_ATTR(in_illuminance_scale_available,
> @@ -130,13 +138,11 @@ static const struct {
> u8 reg;
> u8 val;
> } us5182d_regvals[] = {
> - {US5182D_REG_CFG0, (US5182D_CFG0_SHUTDOWN_EN |
> - US5182D_CFG0_WORD_ENABLE)},
> + {US5182D_REG_CFG0, US5182D_CFG0_WORD_ENABLE},
> {US5182D_REG_CFG1, US5182D_CFG1_ALS_RES16},
> {US5182D_REG_CFG2, (US5182D_CFG2_PX_RES16 |
> US5182D_CFG2_PXGAIN_DEFAULT)},
> {US5182D_REG_CFG3, US5182D_CFG3_LED_CURRENT100},
> - {US5182D_REG_MODE_STORE, US5182D_STORE_MODE},
> {US5182D_REG_CFG4, 0x00},
> };
>
> @@ -169,7 +175,7 @@ static int us5182d_get_als(struct us5182d_data *data)
> return result;
> }
>
> -static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
> +static int us5182d_oneshot_en(struct us5182d_data *data)
> {
> int ret;
>
> @@ -182,6 +188,20 @@ static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
> * required measurement.
> */
> ret = ret | US5182D_CFG0_ONESHOT_EN;
> + return i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG0, ret);
Unwanted extra blank line here...
> +
> +}
> +
> +static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
> +{
> + int ret;
> +
> + if (mode == data->opmode)
> + return 0;
> +
> + ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG0);
> + if (ret < 0)
> + return ret;
>
> /* update mode */
> ret = ret & ~US5182D_OPMODE_MASK;
> @@ -196,9 +216,6 @@ static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
> if (ret < 0)
> return ret;
>
> - if (mode == data->opmode)
> - return 0;
> -
> ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_MODE_STORE,
> US5182D_STORE_MODE);
> if (ret < 0)
> @@ -210,6 +227,23 @@ static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
> return 0;
> }
>
> +static int us5182d_shutdown_en (struct us5182d_data *data, u8 state)
Stray space above.. Checkpatch would have highlighted this for you, please
do run it as a sanity check before you send a series out.

> +{
> + int ret;
> +
> + if (data->power_mode == US5182D_ONESHOT)
> + return 0;
> +
> + ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG0);
> + if (ret < 0)
> + return ret;
> +
> + ret = ret & ~US5182D_CFG0_SHUTDOWN_EN;
> + ret = ret | state;
> +
> + return i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG0, ret);
> +}
> +
> static int us5182d_read_raw(struct iio_dev *indio_dev,
> struct iio_chan_spec const *chan, int *val,
> int *val2, long mask)
> @@ -222,6 +256,11 @@ static int us5182d_read_raw(struct iio_dev *indio_dev,
> switch (chan->type) {
> case IIO_LIGHT:
> mutex_lock(&data->lock);
> + if (data->power_mode == US5182D_ONESHOT) {
> + ret = us5182d_oneshot_en(data);
> + if (ret < 0)
> + goto out_err;
> + }
> ret = us5182d_set_opmode(data, US5182D_OPMODE_ALS);
> if (ret < 0)
> goto out_err;
> @@ -234,6 +273,11 @@ static int us5182d_read_raw(struct iio_dev *indio_dev,
> return IIO_VAL_INT;
> case IIO_PROXIMITY:
> mutex_lock(&data->lock);
> + if (data->power_mode == US5182D_ONESHOT) {
> + ret = us5182d_oneshot_en(data);
> + if (ret < 0)
> + goto out_err;
> + }
> ret = us5182d_set_opmode(data, US5182D_OPMODE_PX);
> if (ret < 0)
> goto out_err;
> @@ -368,6 +412,7 @@ static int us5182d_init(struct iio_dev *indio_dev)
> return ret;
>
> data->opmode = 0;
> + data->power_mode = US5182D_CONTINUOUS;
> for (i = 0; i < ARRAY_SIZE(us5182d_regvals); i++) {
> ret = i2c_smbus_write_byte_data(data->client,
> us5182d_regvals[i].reg,
> @@ -376,7 +421,15 @@ static int us5182d_init(struct iio_dev *indio_dev)
> return ret;
> }
>
> - return 0;
> + if (!data->default_continuous) {
> + ret = us5182d_shutdown_en(data, US5182D_CFG0_SHUTDOWN_EN);
> + if (ret < 0)
> + return ret;
> + data->power_mode = US5182D_ONESHOT;
> + }
> +
> +
> + return ret;
> }
>
> static void us5182d_get_platform_data(struct iio_dev *indio_dev)
> @@ -399,6 +452,8 @@ static void us5182d_get_platform_data(struct iio_dev *indio_dev)
> "upisemi,lower-dark-gain",
> &data->lower_dark_gain))
> data->lower_dark_gain = US5182D_REG_AUTO_LDARK_GAIN_DEFAULT;
> + data->default_continuous = device_property_read_bool(&data->client->dev,
> + "upisemi,continuous");
> }
>
> static int us5182d_dark_gain_config(struct iio_dev *indio_dev)
> @@ -464,16 +519,27 @@ static int us5182d_probe(struct i2c_client *client,
>
> ret = us5182d_dark_gain_config(indio_dev);
> if (ret < 0)
> - return ret;
> + goto out_err;
> +
> + ret = iio_device_register(indio_dev);
> + if (ret < 0)
> + goto out_err;
> +
> + return 0;
> +
> +out_err:
> + us5182d_shutdown_en(data, US5182D_CFG0_SHUTDOWN_EN);
> + return ret;
>
> - return iio_device_register(indio_dev);
> }
>
> static int us5182d_remove(struct i2c_client *client)
> {
> + struct us5182d_data *data = iio_priv(i2c_get_clientdata(client));
> +
> iio_device_unregister(i2c_get_clientdata(client));
> - return i2c_smbus_write_byte_data(client, US5182D_REG_CFG0,
> - US5182D_CFG0_SHUTDOWN_EN);
> +
> + return us5182d_shutdown_en(data, US5182D_CFG0_SHUTDOWN_EN);
> }
>
> static const struct acpi_device_id us5182d_acpi_match[] = {
>