[PATCH] iio: pressure: rohm-bm1390: notify trigger on all error paths

[Stepan Ionichev]

bm1390_trigger_handler() has three error returns:

	if (ret || !status)
		return IRQ_NONE;          /* status read failed */
	...
	if (ret) {
		dev_warn(...);
		return IRQ_NONE;          /* pressure read failed */
	}
	...
	if (ret) {
		dev_warn(...);
		return IRQ_HANDLED;       /* temp read failed */
	}

None of them call iio_trigger_notify_done(). The success path at the
end does, so on a single transient regmap or pressure-read error the
trigger never sees its use_count decremented, and the
!atomic_read(&trig->use_count) guard in iio_trigger_poll_chained()
drops every subsequent dispatch for that trigger. The buffered-data
flow stays wedged until the trigger is detached.

The IRQ_HANDLED return on the temperature path additionally leaves
the temp branch's last partial state in &data->buf.temp without
pushing the sample, which is the existing intended behaviour; only
the missing notify_done() needs fixing.

Funnel all returns through a single 'done' label that calls
iio_trigger_notify_done() before returning the saved irqreturn_t.

Fixes: 81ca5979b6ed ("iio: pressure: Support ROHM BU1390")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Stepan Ionichev <sozdayvek@xxxxxxxxx>
---
 drivers/iio/pressure/rohm-bm1390.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/pressure/rohm-bm1390.c b/drivers/iio/pressure/rohm-bm1390.c
index 08146ca0f..c18352399 100644
--- a/drivers/iio/pressure/rohm-bm1390.c
+++ b/drivers/iio/pressure/rohm-bm1390.c
@@ -626,12 +626,15 @@ static irqreturn_t bm1390_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *idev = pf->indio_dev;
 	struct bm1390_data *data = iio_priv(idev);
+	irqreturn_t result = IRQ_HANDLED;
 	int ret, status;
 
 	/* DRDY is acked by reading status reg */
 	ret = regmap_read(data->regmap, BM1390_REG_STATUS, &status);
-	if (ret || !status)
-		return IRQ_NONE;
+	if (ret || !status) {
+		result = IRQ_NONE;
+		goto done;
+	}
 
 	dev_dbg(data->dev, "DRDY trig status 0x%x\n", status);
 
@@ -639,7 +642,8 @@ static irqreturn_t bm1390_trigger_handler(int irq, void *p)
 		ret = bm1390_pressure_read(data, &data->buf.pressure);
 		if (ret) {
 			dev_warn(data->dev, "sample read failed %d\n", ret);
-			return IRQ_NONE;
+			result = IRQ_NONE;
+			goto done;
 		}
 	}
 
@@ -648,15 +652,16 @@ static irqreturn_t bm1390_trigger_handler(int irq, void *p)
 				       &data->buf.temp, sizeof(data->buf.temp));
 		if (ret) {
 			dev_warn(data->dev, "temp read failed %d\n", ret);
-			return IRQ_HANDLED;
+			goto done;
 		}
 	}
 
 	iio_push_to_buffers_with_ts(idev, &data->buf, sizeof(data->buf),
 				    data->timestamp);
+done:
 	iio_trigger_notify_done(idev->trig);
 
-	return IRQ_HANDLED;
+	return result;
 }
 
 /* Get timestamps and wake the thread if we need to read data */
-- 
2.43.0