@@ -2255,19 +2255,35 @@ st_lsm6dsx_report_motion_event(struct st
static irqreturn_t st_lsm6dsx_handler_thread(int irq, void *private)
{
struct st_lsm6dsx_hw *hw = private;
+ int fifo_len = 0, len;
bool event;
- int count;
event = st_lsm6dsx_report_motion_event(hw);
if (!hw->settings->fifo_ops.read_fifo)
return event ? IRQ_HANDLED : IRQ_NONE;
- mutex_lock(&hw->fifo_lock);
- count = hw->settings->fifo_ops.read_fifo(hw);
- mutex_unlock(&hw->fifo_lock);
+ /*
+ * If we are using edge IRQs, new samples can arrive while
+ * processing current interrupt since there are no hw
+ * guarantees the irq line stays "low" long enough to properly
+ * detect the new interrupt. In this case the new sample will
+ * be missed.
+ * Polling FIFO status register allow us to read new
+ * samples even if the interrupt arrives while processing
+ * previous data and the timeslot where the line is "low" is
+ * too short to be properly detected.
+ */
+ do {
+ mutex_lock(&hw->fifo_lock);
+ len = hw->settings->fifo_ops.read_fifo(hw);
+ mutex_unlock(&hw->fifo_lock);
- return count || event ? IRQ_HANDLED : IRQ_NONE;
+ if (len > 0)
+ fifo_len += len;
+ } while (len > 0);
+
+ return fifo_len || event ? IRQ_HANDLED : IRQ_NONE;
}
static int st_lsm6dsx_irq_setup(struct st_lsm6dsx_hw *hw)