@@ -730,6 +730,11 @@ static irqreturn_t adxl345_trigger_handler(int irq, void *p)
if (int_stat & (ADXL345_INT_DATA_READY | ADXL345_INT_WATERMARK)) {
pr_debug("%s(): WATERMARK or DATA_READY event detected\n", __func__);
+
+ /* Pause measuring, at low watermarks this would easily brick the
+ * sensor in permanent OVERRUN state
+ */
+ adxl345_set_measure_en(st, false);
if (adxl345_get_fifo_entries(st, &fifo_entries) < 0)
goto err;
@@ -737,12 +742,15 @@ static irqreturn_t adxl345_trigger_handler(int irq, void *p)
goto err;
iio_trigger_notify_done(indio_dev->trig);
+ adxl345_set_measure_en(st, true);
}
goto done;
err:
iio_trigger_notify_done(indio_dev->trig);
+ adxl345_set_measure_en(st, false);
adxl345_empty_fifo(st);
+ adxl345_set_measure_en(st, true);
return IRQ_NONE;
done:
Pause the measurement while reading fifo values. Initially an interrupt is triggered if watermark of the FIFO is reached, or in case of OVERRUN. The sensor stays mute until FIFO is cleared and interrupts are read. Situations now can arise when the watermark is configured to a lower value. While reading the values, new values arrive such that a permanent OVERRUN state of the FIFO is reached, i.e. either the FIFO never gets emptied entirely because of permanently new arriving measurements. No more interrupts will be issued and the setup results in OVERRUN. To avoid such situation, stop measuring while solving an OVERRUN condition and generally reading FIFO entries. Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com> --- drivers/iio/accel/adxl345_core.c | 8 ++++++++ 1 file changed, 8 insertions(+)