Kuppuswamy Sathyanarayanan schrieb am 19.04.2015 um 11:10: > Added support to modify and read ALS integration time. Hi, maybe I checked the wrong datasheet [1], but I come to a different conclusion. Please see my comments inline. [1] http://optoelectronics.liteon.com/upload/download/DS86-2012-0006/S_110_LTR-501ALS-01_PrelimDS_ver1%5B1%5D.pdf > > Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> > --- > drivers/iio/light/ltr501.c | 90 +++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 89 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/light/ltr501.c b/drivers/iio/light/ltr501.c > index e2f7354..8092604 100644 > --- a/drivers/iio/light/ltr501.c > +++ b/drivers/iio/light/ltr501.c > @@ -28,6 +28,7 @@ > > #define LTR501_ALS_CONTR 0x80 /* ALS operation mode, SW reset */ > #define LTR501_PS_CONTR 0x81 /* PS operation mode */ > +#define LTR501_ALS_MEAS_RATE 0x85 /* ALS integ time, measurement rate*/ > #define LTR501_PART_ID 0x86 > #define LTR501_MANUFAC_ID 0x87 > #define LTR501_ALS_DATA1 0x88 /* 16-bit, little endian */ > @@ -49,11 +50,17 @@ > > #define LTR501_REGMAP_NAME "ltr501_regmap" > > +static const int int_time_mapping[] = {100000, 50000, 200000, 400000}; The prefix is missing at the instance above and below here. > + > +static const struct reg_field reg_field_it = > + REG_FIELD(LTR501_ALS_MEAS_RATE, 3, 4); > + > struct ltr501_data { > struct i2c_client *client; > struct mutex lock_als, lock_ps; > u8 als_contr, ps_contr; > struct regmap *regmap; > + struct regmap_field *reg_it; > }; > > static int ltr501_drdy(struct ltr501_data *data, u8 drdy_mask) > @@ -74,6 +81,58 @@ static int ltr501_drdy(struct ltr501_data *data, u8 drdy_mask) > return -EIO; > } > > +static int ltr501_set_it_time(struct ltr501_data *data, int it) > +{ > + int ret, i, index = -1, status; > + > + for (i = 0; i < ARRAY_SIZE(int_time_mapping); i++) { > + if (int_time_mapping[i] == it) { > + index = i; > + break; > + } > + } > + /* Make sure integ time index is valid */ > + if (index < 0) > + return -EINVAL; > + > + ret = regmap_read(data->regmap, LTR501_ALS_CONTR, &status); > + if (ret < 0) > + return ret; > + > + if (status & LTR501_CONTR_ALS_GAIN_MASK) { According to the description on page 17, if ALS Gain is set Dynamic Range 1 is selected. So, as mentioned on page 20, valid index values would be 0, 2 and 3 (meaning invalid value is 1). > + /* > + * 200 ms and 400 ms integ time can only be > + * used in dynamic range 1 > + */ > + if (index > 1) > + return -EINVAL; > + } else Coding style guidelines prefer to put the else-part in {}, if the if-part is in {}. Anyway, my interpretation of the datasheet suggests that this part expects Dynamic Range 2 to be selected. Valid values are: 0 and 1 (invalid are 2 and 3). Thanks, Hartmut > + /* 50 ms integ time can only be used in dynamic range 2 */ > + if (index == 1) > + return -EINVAL; > + > + return regmap_field_write(data->reg_it, index); > +} > + > +/* read int time in micro seconds */ > +static int ltr501_read_it_time(struct ltr501_data *data, int *val, int *val2) > +{ > + int ret, index; > + > + ret = regmap_field_read(data->reg_it, &index); > + if (ret < 0) > + return ret; > + > + /* Make sure integ time index is valid */ > + if (index < 0 || index >= ARRAY_SIZE(int_time_mapping)) > + return -EINVAL; > + > + *val2 = int_time_mapping[index]; > + *val = 0; > + > + return IIO_VAL_INT_PLUS_MICRO; > +} > + > static int ltr501_read_als(struct ltr501_data *data, __le16 buf[2]) > { > int ret; > @@ -121,7 +180,8 @@ static int ltr501_read_ps(struct ltr501_data *data) > static const struct iio_chan_spec ltr501_channels[] = { > LTR501_INTENSITY_CHANNEL(0, LTR501_ALS_DATA0, IIO_MOD_LIGHT_BOTH, 0), > LTR501_INTENSITY_CHANNEL(1, LTR501_ALS_DATA1, IIO_MOD_LIGHT_IR, > - BIT(IIO_CHAN_INFO_SCALE)), > + BIT(IIO_CHAN_INFO_SCALE) | > + BIT(IIO_CHAN_INFO_INT_TIME)), > { > .type = IIO_PROXIMITY, > .address = LTR501_PS_DATA, > @@ -196,6 +256,13 @@ static int ltr501_read_raw(struct iio_dev *indio_dev, > default: > return -EINVAL; > } > + case IIO_CHAN_INFO_INT_TIME: > + switch (chan->type) { > + case IIO_INTENSITY: > + return ltr501_read_it_time(data, val, val2); > + default: > + return -EINVAL; > + } > } > return -EINVAL; > } > @@ -246,16 +313,30 @@ static int ltr501_write_raw(struct iio_dev *indio_dev, > default: > return -EINVAL; > } > + case IIO_CHAN_INFO_INT_TIME: > + switch (chan->type) { > + case IIO_INTENSITY: > + if (val != 0) > + return -EINVAL; > + mutex_lock(&data->lock_als); > + i = ltr501_set_it_time(data, val2); > + mutex_unlock(&data->lock_als); > + return i; > + default: > + return -EINVAL; > + } > } > return -EINVAL; > } > > static IIO_CONST_ATTR(in_proximity_scale_available, "1 0.25 0.125 0.0625"); > static IIO_CONST_ATTR(in_intensity_scale_available, "1 0.005"); > +static IIO_CONST_ATTR_INT_TIME_AVAIL("0.05 0.1 0.2 0.4"); > > static struct attribute *ltr501_attributes[] = { > &iio_const_attr_in_proximity_scale_available.dev_attr.attr, > &iio_const_attr_in_intensity_scale_available.dev_attr.attr, > + &iio_const_attr_integration_time_available.dev_attr.attr, > NULL > }; > > @@ -404,6 +485,13 @@ static int ltr501_probe(struct i2c_client *client, > mutex_init(&data->lock_als); > mutex_init(&data->lock_ps); > > + data->reg_it = devm_regmap_field_alloc(&client->dev, regmap, > + reg_field_it); > + if (IS_ERR(data->reg_it)) { > + dev_err(&client->dev, "Integ time reg field init failed.\n"); > + return PTR_ERR(data->reg_it); > + } > + > ret = regmap_read(data->regmap, LTR501_PART_ID, &partid); > if (ret < 0) > return ret; > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
