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@xxxxxxxxx> --- 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); + +} + +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) +{ + 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[] = { -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html