Introduce means to configure and work with the available g-ranges keeping the precision of 13 digits. This is in preparation for the activity/inactivity feature. Signed-off-by: Lothar Rubusch <l.rubusch@xxxxxxxxx> --- drivers/iio/accel/adxl345_core.c | 92 ++++++++++++++++++++++++++++++-- 1 file changed, 89 insertions(+), 3 deletions(-) diff --git a/drivers/iio/accel/adxl345_core.c b/drivers/iio/accel/adxl345_core.c index 08ad71875c5e..ea7bfe193d31 100644 --- a/drivers/iio/accel/adxl345_core.c +++ b/drivers/iio/accel/adxl345_core.c @@ -86,6 +86,13 @@ enum adxl345_odr { ADXL345_ODR_3200HZ, }; +enum adxl345_range { + ADXL345_2G_RANGE = 0, + ADXL345_4G_RANGE, + ADXL345_8G_RANGE, + ADXL345_16G_RANGE, +}; + /* Certain features recommend 12.5 Hz - 400 Hz ODR */ static const int adxl345_odr_tbl[][2] = { [ADXL345_ODR_0P10HZ] = { 0, 97000}, @@ -106,6 +113,33 @@ static const int adxl345_odr_tbl[][2] = { [ADXL345_ODR_3200HZ] = {3200, 0}, }; +/* + * Full resolution frequency table: + * (g * 2 * 9.80665) / (2^(resolution) - 1) + * + * resolution := 13 (full) + * g := 2|4|8|16 + * + * 2g at 13bit: 0.004789 + * 4g at 13bit: 0.009578 + * 8g at 13bit: 0.019156 + * 16g at 16bit: 0.038312 + */ +static const int adxl345_fullres_range_tbl[][2] = { + [ADXL345_2G_RANGE] = {0, 4789}, + [ADXL345_4G_RANGE] = {0, 9578}, + [ADXL345_8G_RANGE] = {0, 19156}, + [ADXL345_16G_RANGE] = {0, 38312}, +}; + +/* scaling */ +static const int adxl345_range_factor_tbl[] = { + [ADXL345_2G_RANGE] = 1, + [ADXL345_4G_RANGE] = 2, + [ADXL345_8G_RANGE] = 4, + [ADXL345_16G_RANGE] = 8, +}; + struct adxl345_state { const struct adxl345_chip_info *info; struct regmap *regmap; @@ -117,6 +151,7 @@ struct adxl345_state { u8 fifo_mode; enum adxl345_odr odr; + enum adxl345_range range; u32 tap_axis_ctrl; u8 tap_threshold; @@ -167,7 +202,8 @@ static struct iio_event_spec adxl345_events[] = { BIT(IIO_CHAN_INFO_CALIBBIAS), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ BIT(IIO_CHAN_INFO_SAMP_FREQ), \ - .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ .scan_index = (index), \ .scan_type = { \ .sign = 's', \ @@ -502,12 +538,50 @@ static int adxl345_set_odr(struct adxl345_state *st, enum adxl345_odr odr) return 0; } +static int adxl345_find_range(struct adxl345_state *st, int val, int val2, + enum adxl345_range *range) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(adxl345_fullres_range_tbl); i++) + if (val == adxl345_fullres_range_tbl[i][0] && + val2 == adxl345_fullres_range_tbl[i][1]) + break; + + if (i == ARRAY_SIZE(adxl345_fullres_range_tbl)) + return -EINVAL; + + *range = i; + + return 0; +} + +static int adxl345_set_range(struct adxl345_state *st, enum adxl345_range range) +{ + int ret; + + ret = regmap_update_bits(st->regmap, ADXL345_REG_DATA_FORMAT, + ADXL345_DATA_FORMAT_RANGE, + FIELD_PREP(ADXL345_DATA_FORMAT_RANGE, range)); + if (ret) + return ret; + + st->range = range; + + return 0; +} + static int adxl345_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, const int **vals, int *type, int *length, long mask) { switch (mask) { + case IIO_CHAN_INFO_SCALE: + *vals = (int *)adxl345_fullres_range_tbl; + *type = IIO_VAL_INT_PLUS_MICRO; + *length = ARRAY_SIZE(adxl345_fullres_range_tbl) * 2; + return IIO_AVAIL_LIST; case IIO_CHAN_INFO_SAMP_FREQ: *vals = (int *)adxl345_odr_tbl; *type = IIO_VAL_INT_PLUS_MICRO; @@ -543,8 +617,8 @@ static int adxl345_read_raw(struct iio_dev *indio_dev, *val = sign_extend32(le16_to_cpu(accel), 12); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: - *val = 0; - *val2 = st->info->uscale; + *val = adxl345_fullres_range_tbl[st->range][0]; + *val2 = adxl345_fullres_range_tbl[st->range][1]; return IIO_VAL_INT_PLUS_MICRO; case IIO_CHAN_INFO_CALIBBIAS: ret = regmap_read(st->regmap, @@ -572,6 +646,7 @@ static int adxl345_write_raw(struct iio_dev *indio_dev, int val, int val2, long mask) { struct adxl345_state *st = iio_priv(indio_dev); + enum adxl345_range range; enum adxl345_odr odr; int ret; @@ -595,6 +670,12 @@ static int adxl345_write_raw(struct iio_dev *indio_dev, return ret; ret = adxl345_set_odr(st, odr); break; + case IIO_CHAN_INFO_SCALE: + ret = adxl345_find_range(st, val, val2, &range); + if (ret) + return ret; + ret = adxl345_set_range(st, range); + break; default: return -EINVAL; } @@ -833,6 +914,8 @@ static int adxl345_write_raw_get_fmt(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_CALIBBIAS: return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + return IIO_VAL_INT_PLUS_MICRO; case IIO_CHAN_INFO_SAMP_FREQ: return IIO_VAL_INT_PLUS_MICRO; default: @@ -1252,6 +1335,9 @@ int adxl345_core_probe(struct device *dev, struct regmap *regmap, * undesired behavior. */ ret = adxl345_set_odr(st, ADXL345_ODR_200HZ); + if (ret) + return ret; + ret = adxl345_set_range(st, ADXL345_16G_RANGE); if (ret) return ret; -- 2.39.5