[PATCH v2 1/3] iio: accel: adxl372: Fix/remove limitation for FIFO samples

Stefan Popa
2019-09-10T14:44:20Z

Currently, the driver sets the FIFO_SAMPLES register with the number of
sample sets (maximum of 170 for 3 axis data, 256 for 2-axis and 512 for
single axis). However, the FIFO_SAMPLES register should store the number
of samples, regardless of how the FIFO format is configured.

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
---
Changes in v2:
- st->watermark needs to store the number of sample sets,
the total number of samples is computed in
adxl372_configure_fifo() func.

drivers/iio/accel/adxl372.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
index 055227cb..7de5e1b 100644
--- a/drivers/iio/accel/adxl372.c
+++ b/drivers/iio/accel/adxl372.c
@@ -474,12 +474,17 @@ static int adxl372_configure_fifo(struct adxl372_state *st)
if (ret < 0)
return ret;

- fifo_samples = st->watermark & 0xFF;
+ /*
+ * watermak stores the number of sets; we need to write the FIFO
+ * registers with the number of samples
+ */
+ fifo_samples = (st->watermark * st->fifo_set_size);
fifo_ctl = ADXL372_FIFO_CTL_FORMAT_MODE(st->fifo_format) |
ADXL372_FIFO_CTL_MODE_MODE(st->fifo_mode) |
- ADXL372_FIFO_CTL_SAMPLES_MODE(st->watermark);
+ ADXL372_FIFO_CTL_SAMPLES_MODE(fifo_samples);

- ret = regmap_write(st->regmap, ADXL372_FIFO_SAMPLES, fifo_samples);
+ ret = regmap_write(st->regmap,
+ ADXL372_FIFO_SAMPLES, fifo_samples & 0xFF);
if (ret < 0)
return ret;

--
2.7.4