Export the oversampling ratio so that the user can change the number of repetions for x/y/z axis. The sampling frequency is limited by the oversampling ratio. The available sampling frequencies might change depending on the values of oversampling_ratio. The specification can be downloaded from: http://ae-bst.resource.bosch.com/media/products/dokumente/bmc150/BST-BMC150-DS000-04.pdf. Signed-off-by: Irina Tirdea <irina.tirdea@xxxxxxxxx> --- drivers/iio/magnetometer/bmc150_magn.c | 133 ++++++++++++++++++++++++++++++++- 1 file changed, 129 insertions(+), 4 deletions(-) diff --git a/drivers/iio/magnetometer/bmc150_magn.c b/drivers/iio/magnetometer/bmc150_magn.c index 7bbaea8..d4c1788 100644 --- a/drivers/iio/magnetometer/bmc150_magn.c +++ b/drivers/iio/magnetometer/bmc150_magn.c @@ -146,6 +146,7 @@ struct bmc150_magn_data { s32 buffer[6]; struct iio_trigger *dready_trig; bool dready_trigger_on; + int max_odr; }; static const struct { @@ -323,6 +324,43 @@ static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val) return -EINVAL; } +static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy, + int rep_z, int odr) +{ + int ret, reg_val, max_odr; + + if (rep_xy <= 0) { + ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY, + ®_val); + if (ret < 0) + return ret; + rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val); + } + if (rep_z <= 0) { + ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z, + ®_val); + if (ret < 0) + return ret; + rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val); + } + if (odr <= 0) { + ret = bmc150_magn_get_odr(data, &odr); + if (ret < 0) + return ret; + } + /* the maximum selectable read-out frequency from datasheet */ + max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980); + if (odr > max_odr) { + dev_err(&data->client->dev, + "Can't set oversampling with sampling freq %d\n", + odr); + return -EINVAL; + } + data->max_odr = max_odr; + + return 0; +} + static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x, u16 rhall) { @@ -422,7 +460,7 @@ static int bmc150_magn_read_raw(struct iio_dev *indio_dev, int *val, int *val2, long mask) { struct bmc150_magn_data *data = iio_priv(indio_dev); - int ret; + int ret, tmp; s32 values[AXIS_XYZ_MAX]; switch (mask) { @@ -467,6 +505,26 @@ static int bmc150_magn_read_raw(struct iio_dev *indio_dev, if (ret < 0) return ret; return IIO_VAL_INT; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + switch (chan->channel2) { + case IIO_MOD_X: + case IIO_MOD_Y: + ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY, + &tmp); + if (ret < 0) + return ret; + *val = BMC150_MAGN_REGVAL_TO_REPXY(tmp); + return IIO_VAL_INT; + case IIO_MOD_Z: + ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z, + &tmp); + if (ret < 0) + return ret; + *val = BMC150_MAGN_REGVAL_TO_REPZ(tmp); + return IIO_VAL_INT; + default: + return -EINVAL; + } default: return -EINVAL; } @@ -481,10 +539,50 @@ static int bmc150_magn_write_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: + if (val > data->max_odr) + return -EINVAL; mutex_lock(&data->mutex); ret = bmc150_magn_set_odr(data, val); mutex_unlock(&data->mutex); return ret; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + switch (chan->channel2) { + case IIO_MOD_X: + case IIO_MOD_Y: + if (val < 1 || val > 511) + return -EINVAL; + mutex_lock(&data->mutex); + ret = bmc150_magn_set_max_odr(data, val, 0, 0); + if (ret < 0) { + mutex_unlock(&data->mutex); + return ret; + } + ret = regmap_update_bits(data->regmap, + BMC150_MAGN_REG_REP_XY, + 0xFF, + BMC150_MAGN_REPXY_TO_REGVAL + (val)); + mutex_unlock(&data->mutex); + return ret; + case IIO_MOD_Z: + if (val < 1 || val > 256) + return -EINVAL; + mutex_lock(&data->mutex); + ret = bmc150_magn_set_max_odr(data, 0, val, 0); + if (ret < 0) { + mutex_unlock(&data->mutex); + return ret; + } + ret = regmap_update_bits(data->regmap, + BMC150_MAGN_REG_REP_Z, + 0xFF, + BMC150_MAGN_REPZ_TO_REGVAL + (val)); + mutex_unlock(&data->mutex); + return ret; + default: + return -EINVAL; + } default: return -EINVAL; } @@ -501,10 +599,31 @@ static int bmc150_magn_validate_trigger(struct iio_dev *indio_dev, return 0; } -static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("2 6 8 10 15 20 25 30"); +static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct bmc150_magn_data *data = iio_priv(indio_dev); + size_t len = 0; + u8 i; + + for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) { + if (bmc150_magn_samp_freq_table[i].freq > data->max_odr) + break; + len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", + bmc150_magn_samp_freq_table[i].freq); + } + /* replace last space with a newline */ + buf[len - 1] = '\n'; + + return len; +} + +static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail); static struct attribute *bmc150_magn_attributes[] = { - &iio_const_attr_sampling_frequency_available.dev_attr.attr, + &iio_dev_attr_sampling_frequency_available.dev_attr.attr, NULL, }; @@ -516,7 +635,8 @@ static const struct attribute_group bmc150_magn_attrs_group = { .type = IIO_MAGN, \ .modified = 1, \ .channel2 = IIO_MOD_##_axis, \ - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \ BIT(IIO_CHAN_INFO_SCALE), \ .scan_index = AXIS_##_axis, \ @@ -616,6 +736,11 @@ static int bmc150_magn_init(struct bmc150_magn_data *data) goto err_poweroff; } + ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z, + preset.odr); + if (ret < 0) + goto err_poweroff; + ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL, true); if (ret < 0) { -- 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
