| Message ID | 1533301341-26560-6-git-send-email-stefan.popa@analog.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: accel: Add adxl372 driver | expand |
On Fri, 3 Aug 2018 16:02:20 +0300 Stefan Popa <stefan.popa@analog.com> wrote: > This patch adds the option for the user to select the sampling frequency. > Also, the user can read the available frequencies and read the currently > set frequency via the read_raw function. The frequency can be set via the > write_raw function. > > When the frequency is set, the bandwidth is also checked and ensured > that it is constrained to at most half of the sampling frequency. Also, the > activity and inactivity timers have to be updated because they depend on > the selected ODR. > > Signed-off-by: Stefan Popa <stefan.popa@analog.com> This one is good. Will pick up with the others unless someone finds an issue in the meantime. Thanks, Jonathan > --- > drivers/iio/accel/adxl372.c | 74 ++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 73 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c > index e31e096..80b1838 100644 > --- a/drivers/iio/accel/adxl372.c > +++ b/drivers/iio/accel/adxl372.c > @@ -217,7 +217,8 @@ static const struct adxl372_axis_lookup adxl372_axis_lookup_table[] = { > .modified = 1, \ > .channel2 = IIO_MOD_##axis, \ > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > - .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ > .scan_index = index, \ > .scan_type = { \ > .sign = 's', \ > @@ -311,6 +312,19 @@ static int adxl372_set_odr(struct adxl372_state *st, > return ret; > } > > +static int adxl372_find_closest_match(const int *array, > + unsigned int size, int val) > +{ > + int i; > + > + for (i = 0; i < size; i++) { > + if (val <= array[i]) > + return i; > + } > + > + return size - 1; > +} > + > static int adxl372_set_bandwidth(struct adxl372_state *st, > enum adxl372_bandwidth bw) > { > @@ -639,6 +653,51 @@ static int adxl372_read_raw(struct iio_dev *indio_dev, > *val = 0; > *val2 = ADXL372_USCALE; > return IIO_VAL_INT_PLUS_MICRO; > + case IIO_CHAN_INFO_SAMP_FREQ: > + *val = adxl372_samp_freq_tbl[st->odr]; > + return IIO_VAL_INT; > + } > + > + return -EINVAL; > +} > + > +static int adxl372_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long info) > +{ > + struct adxl372_state *st = iio_priv(indio_dev); > + int odr_index, ret; > + > + switch (info) { > + case IIO_CHAN_INFO_SAMP_FREQ: > + odr_index = adxl372_find_closest_match(adxl372_samp_freq_tbl, > + ARRAY_SIZE(adxl372_samp_freq_tbl), > + val); > + ret = adxl372_set_odr(st, odr_index); > + if (ret < 0) > + return ret; > + /* > + * The timer period depends on the ODR selected. > + * At 3200 Hz and below, it is 6.6 ms; at 6400 Hz, it is 3.3 ms > + */ > + ret = adxl372_set_activity_time_ms(st, st->act_time_ms); > + if (ret < 0) > + return ret; > + /* > + * The timer period depends on the ODR selected. > + * At 3200 Hz and below, it is 26 ms; at 6400 Hz, it is 13 ms > + */ > + ret = adxl372_set_inactivity_time_ms(st, st->inact_time_ms); > + if (ret < 0) > + return ret; > + /* > + * The maximum bandwidth is constrained to at most half of > + * the ODR to ensure that the Nyquist criteria is not violated > + */ > + if (st->bw > odr_index) > + ret = adxl372_set_bandwidth(st, odr_index); > + > + return ret; > default: > return -EINVAL; > } > @@ -766,8 +825,21 @@ static const struct iio_trigger_ops adxl372_trigger_ops = { > .set_trigger_state = adxl372_dready_trig_set_state, > }; > > +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("400 800 1600 3200 6400"); > + > +static struct attribute *adxl372_attributes[] = { > + &iio_const_attr_sampling_frequency_available.dev_attr.attr, > + NULL, > +}; > + > +static const struct attribute_group adxl372_attrs_group = { > + .attrs = adxl372_attributes, > +}; > + > static const struct iio_info adxl372_info = { > + .attrs = &adxl372_attrs_group, > .read_raw = adxl372_read_raw, > + .write_raw = adxl372_write_raw, > .debugfs_reg_access = &adxl372_reg_access, > .hwfifo_set_watermark = adxl372_set_watermark, > }; -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c index e31e096..80b1838 100644 --- a/drivers/iio/accel/adxl372.c +++ b/drivers/iio/accel/adxl372.c @@ -217,7 +217,8 @@ static const struct adxl372_axis_lookup adxl372_axis_lookup_table[] = { .modified = 1, \ .channel2 = IIO_MOD_##axis, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ - .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ .scan_index = index, \ .scan_type = { \ .sign = 's', \ @@ -311,6 +312,19 @@ static int adxl372_set_odr(struct adxl372_state *st, return ret; } +static int adxl372_find_closest_match(const int *array, + unsigned int size, int val) +{ + int i; + + for (i = 0; i < size; i++) { + if (val <= array[i]) + return i; + } + + return size - 1; +} + static int adxl372_set_bandwidth(struct adxl372_state *st, enum adxl372_bandwidth bw) { @@ -639,6 +653,51 @@ static int adxl372_read_raw(struct iio_dev *indio_dev, *val = 0; *val2 = ADXL372_USCALE; return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_SAMP_FREQ: + *val = adxl372_samp_freq_tbl[st->odr]; + return IIO_VAL_INT; + } + + return -EINVAL; +} + +static int adxl372_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long info) +{ + struct adxl372_state *st = iio_priv(indio_dev); + int odr_index, ret; + + switch (info) { + case IIO_CHAN_INFO_SAMP_FREQ: + odr_index = adxl372_find_closest_match(adxl372_samp_freq_tbl, + ARRAY_SIZE(adxl372_samp_freq_tbl), + val); + ret = adxl372_set_odr(st, odr_index); + if (ret < 0) + return ret; + /* + * The timer period depends on the ODR selected. + * At 3200 Hz and below, it is 6.6 ms; at 6400 Hz, it is 3.3 ms + */ + ret = adxl372_set_activity_time_ms(st, st->act_time_ms); + if (ret < 0) + return ret; + /* + * The timer period depends on the ODR selected. + * At 3200 Hz and below, it is 26 ms; at 6400 Hz, it is 13 ms + */ + ret = adxl372_set_inactivity_time_ms(st, st->inact_time_ms); + if (ret < 0) + return ret; + /* + * The maximum bandwidth is constrained to at most half of + * the ODR to ensure that the Nyquist criteria is not violated + */ + if (st->bw > odr_index) + ret = adxl372_set_bandwidth(st, odr_index); + + return ret; default: return -EINVAL; } @@ -766,8 +825,21 @@ static const struct iio_trigger_ops adxl372_trigger_ops = { .set_trigger_state = adxl372_dready_trig_set_state, }; +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("400 800 1600 3200 6400"); + +static struct attribute *adxl372_attributes[] = { + &iio_const_attr_sampling_frequency_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group adxl372_attrs_group = { + .attrs = adxl372_attributes, +}; + static const struct iio_info adxl372_info = { + .attrs = &adxl372_attrs_group, .read_raw = adxl372_read_raw, + .write_raw = adxl372_write_raw, .debugfs_reg_access = &adxl372_reg_access, .hwfifo_set_watermark = adxl372_set_watermark, };
This patch adds the option for the user to select the sampling frequency. Also, the user can read the available frequencies and read the currently set frequency via the read_raw function. The frequency can be set via the write_raw function. When the frequency is set, the bandwidth is also checked and ensured that it is constrained to at most half of the sampling frequency. Also, the activity and inactivity timers have to be updated because they depend on the selected ODR. Signed-off-by: Stefan Popa <stefan.popa@analog.com> --- drivers/iio/accel/adxl372.c | 74 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 73 insertions(+), 1 deletion(-)