[PATCH v1 04/12] iio: accel: adxl345: reorganize irq handler

[Lothar Rubusch <l.rubusch@gmail.com>]

Reorganize the IRQ handler. Move the overrun handling to the bottom.
Overrun leads to reset the interrupt register. This also happens at
evaluation of a particular interrupt event. So, actually it makes more
sense to evaluate the event if possible, and only fall back to pure
overrun handling as a last resort. Further simplify fetching the
interrupt status function. Both is in preparation to build interrupt
handling up for the handling of different detected events, implemented
in follow up patches.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl345_core.c | 23 ++++++++---------------
 1 file changed, 8 insertions(+), 15 deletions(-)

diff --git a/drivers/iio/accel/adxl345_core.c b/drivers/iio/accel/adxl345_core.c
index 8fbf0a43746f..7ee50a0b23ea 100644
--- a/drivers/iio/accel/adxl345_core.c
+++ b/drivers/iio/accel/adxl345_core.c
@@ -491,16 +491,9 @@ static const struct iio_buffer_setup_ops adxl345_buffer_ops = {
 	.predisable = adxl345_buffer_predisable,
 };
 
-static int adxl345_get_status(struct adxl345_state *st)
+static int adxl345_get_status(struct adxl345_state *st, unsigned int *int_stat)
 {
-	int ret;
-	unsigned int regval;
-
-	ret = regmap_read(st->regmap, ADXL345_REG_INT_SOURCE, &regval);
-	if (ret < 0)
-		return ret;
-
-	return FIELD_GET(ADXL345_REG_INT_SOURCE_MSK, regval);
+	return regmap_read(st->regmap, ADXL345_REG_INT_SOURCE, int_stat);
 }
 
 static int adxl345_fifo_push(struct iio_dev *indio_dev,
@@ -536,14 +529,10 @@ static irqreturn_t adxl345_irq_handler(int irq, void *p)
 	int int_stat;
 	int samples;
 
-	int_stat = adxl345_get_status(st);
-	if (int_stat <= 0)
+	if (adxl345_get_status(st, &int_stat))
 		return IRQ_NONE;
 
-	if (int_stat & ADXL345_INT_OVERRUN)
-		goto err;
-
-	if (int_stat & ADXL345_INT_WATERMARK) {
+	if (FIELD_GET(ADXL345_INT_WATERMARK, int_stat)) {
 		samples = adxl345_get_samples(st);
 		if (samples < 0)
 			goto err;
@@ -551,6 +540,10 @@ static irqreturn_t adxl345_irq_handler(int irq, void *p)
 		if (adxl345_fifo_push(indio_dev, samples) < 0)
 			goto err;
 	}
+
+	if (FIELD_GET(ADXL345_INT_OVERRUN, int_stat))
+		goto err;
+
 	return IRQ_HANDLED;
 
 err:
-- 
2.39.5