| Message ID | 20200225120909.12629-2-alexandru.tachici@analog.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: accel: adxl372: add peak mode | expand |
On Tue, 25 Feb 2020 14:09:04 +0200 Alexandru Tachici <alexandru.tachici@analog.com> wrote: > From: Stefan Popa <stefan.popa@analog.com> > > By default, if all three channels (x, y, z) are enabled, sample sets of > concurrent 3-axis data is stored in the FIFO. This patch adds the option > to configure the FIFO to store peak acceleration (x, y and z) of every > over-threshold event. Since we cannot store 1 or 2 axis peak acceleration > data in the FIFO, then all three axis need to be enabled in order for this > mode to work. > > Signed-off-by: Stefan Popa <stefan.popa@analog.com> First apologies this was one of the sets that I didn't get to last week. This is a bit of an odd one, but I suppose the general approach is fine. A few questions on specifics inline. > --- > drivers/iio/accel/adxl372.c | 46 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 46 insertions(+) > > diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c > index 67b8817995c0..ed93534f8dba 100644 > --- a/drivers/iio/accel/adxl372.c > +++ b/drivers/iio/accel/adxl372.c > @@ -264,6 +264,7 @@ struct adxl372_state { > u8 int2_bitmask; > u16 watermark; > __be16 fifo_buf[ADXL372_FIFO_SIZE]; > + bool peak_fifo_mode_en; > }; > > static const unsigned long adxl372_channel_masks[] = { > @@ -722,6 +723,40 @@ static int adxl372_write_raw(struct iio_dev *indio_dev, > } > } > > +static ssize_t adxl372_peak_fifo_en_get(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct adxl372_state *st = iio_priv(dev_to_iio_dev(dev)); > + > + return sprintf(buf, "%d\n", st->peak_fifo_mode_en); > +} > + > +static ssize_t adxl372_peak_fifo_en_set(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t len) > +{ > + struct iio_dev *indio_dev = dev_to_iio_dev(dev); > + struct adxl372_state *st = iio_priv(indio_dev); > + bool val; > + int ret; > + > + if (iio_buffer_enabled(indio_dev)) > + return -EBUSY; Prefer if you use the iio_claim_direct_mode to ensure we are in non buffered mode until we reach a consistent state. Then set the variable and release direct mode. Otherwise you might have a race between a write to this and enabling the buffered mode. > + > + ret = kstrtobool(buf, &val); > + if (ret) > + return ret; > + > + st->peak_fifo_mode_en = val; > + > + return len; > +} > + > +static IIO_DEVICE_ATTR(buffer_peak_mode_enable, 0644, > + adxl372_peak_fifo_en_get, > + adxl372_peak_fifo_en_set, 0); > + > static ssize_t adxl372_show_filter_freq_avail(struct device *dev, > struct device_attribute *attr, > char *buf) > @@ -817,11 +852,21 @@ static int adxl372_buffer_postenable(struct iio_dev *indio_dev) > st->fifo_format = adxl372_axis_lookup_table[i].fifo_format; > st->fifo_set_size = bitmap_weight(indio_dev->active_scan_mask, > indio_dev->masklength); > + > + /* Configure the FIFO to store sets of impact event peak. */ > + if (st->peak_fifo_mode_en) { > + st->fifo_format = ADXL372_XYZ_PEAK_FIFO; > + if (st->fifo_set_size != 3) > + dev_warn(&indio_dev->dev, > + "All axis must be enabled in peak mode."); What happens otherwise? Real question is should this just be an error and result in us dropping out of buffered mode again? How would a userspace program that had hit this know there was an issue? > + } > + > /* > * The 512 FIFO samples can be allotted in several ways, such as: > * 170 sample sets of concurrent 3-axis data > * 256 sample sets of concurrent 2-axis data (user selectable) > * 512 sample sets of single-axis data > + * 170 sets of impact event peak (x, y, z) > */ > if ((st->watermark * st->fifo_set_size) > ADXL372_FIFO_SIZE) > st->watermark = (ADXL372_FIFO_SIZE / st->fifo_set_size); > @@ -894,6 +939,7 @@ static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available, > static struct attribute *adxl372_attributes[] = { > &iio_const_attr_sampling_frequency_available.dev_attr.attr, > &iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr, > + &iio_dev_attr_buffer_peak_mode_enable.dev_attr.attr, > NULL, > }; >
diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c index 67b8817995c0..ed93534f8dba 100644 --- a/drivers/iio/accel/adxl372.c +++ b/drivers/iio/accel/adxl372.c @@ -264,6 +264,7 @@ struct adxl372_state { u8 int2_bitmask; u16 watermark; __be16 fifo_buf[ADXL372_FIFO_SIZE]; + bool peak_fifo_mode_en; }; static const unsigned long adxl372_channel_masks[] = { @@ -722,6 +723,40 @@ static int adxl372_write_raw(struct iio_dev *indio_dev, } } +static ssize_t adxl372_peak_fifo_en_get(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct adxl372_state *st = iio_priv(dev_to_iio_dev(dev)); + + return sprintf(buf, "%d\n", st->peak_fifo_mode_en); +} + +static ssize_t adxl372_peak_fifo_en_set(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct adxl372_state *st = iio_priv(indio_dev); + bool val; + int ret; + + if (iio_buffer_enabled(indio_dev)) + return -EBUSY; + + ret = kstrtobool(buf, &val); + if (ret) + return ret; + + st->peak_fifo_mode_en = val; + + return len; +} + +static IIO_DEVICE_ATTR(buffer_peak_mode_enable, 0644, + adxl372_peak_fifo_en_get, + adxl372_peak_fifo_en_set, 0); + static ssize_t adxl372_show_filter_freq_avail(struct device *dev, struct device_attribute *attr, char *buf) @@ -817,11 +852,21 @@ static int adxl372_buffer_postenable(struct iio_dev *indio_dev) st->fifo_format = adxl372_axis_lookup_table[i].fifo_format; st->fifo_set_size = bitmap_weight(indio_dev->active_scan_mask, indio_dev->masklength); + + /* Configure the FIFO to store sets of impact event peak. */ + if (st->peak_fifo_mode_en) { + st->fifo_format = ADXL372_XYZ_PEAK_FIFO; + if (st->fifo_set_size != 3) + dev_warn(&indio_dev->dev, + "All axis must be enabled in peak mode."); + } + /* * The 512 FIFO samples can be allotted in several ways, such as: * 170 sample sets of concurrent 3-axis data * 256 sample sets of concurrent 2-axis data (user selectable) * 512 sample sets of single-axis data + * 170 sets of impact event peak (x, y, z) */ if ((st->watermark * st->fifo_set_size) > ADXL372_FIFO_SIZE) st->watermark = (ADXL372_FIFO_SIZE / st->fifo_set_size); @@ -894,6 +939,7 @@ static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available, static struct attribute *adxl372_attributes[] = { &iio_const_attr_sampling_frequency_available.dev_attr.attr, &iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr, + &iio_dev_attr_buffer_peak_mode_enable.dev_attr.attr, NULL, };