[PATCH v2] iio: proximity: vl53l0x: notify trigger and clear IRQ on error paths

[PATCH v2] iio: proximity: vl53l0x: notify trigger and clear IRQ on error paths

[Stepan Ionichev]

vl53l0x_trigger_handler() returns directly on the I2C read failure
paths without calling iio_trigger_notify_done() or vl53l0x_clear_irq().

A single transient i2c_smbus_read_i2c_block_data() failure (negative
errno or a short read) therefore leaves two pieces of state behind:

  - iio_trigger_notify_done() never decrements the trigger's use_count,
    so iio_trigger_poll_nested() silently drops further dispatches
    (see industrialio-trigger.c, the !atomic_read(&trig->use_count)
    guard);
  - vl53l0x_clear_irq() never writes SYSTEM_INTERRUPT_CLEAR, so the
    chip keeps the DRDY interrupt asserted.

The sensor's buffer mode stays wedged from then on, recoverable only
by re-binding the driver. The sibling driver vl53l1x-i2c.c handles
exactly the same case correctly by jumping to a "notify_and_clear_irq"
label that always calls both helpers; mirror that here.

The bogus negative-int return value cast to irqreturn_t also goes
away as a side effect.

Fixes: 762186c6e7b1 ("iio: proximity: vl53l0x-i2c: Added continuous mode support")
Signed-off-by: Stepan Ionichev <sozdayvek@gmail.com>
---
v2:
- Drop the cited error-path code from the commit body; the diff
  already shows it (per Andy)

 drivers/iio/proximity/vl53l0x-i2c.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/proximity/vl53l0x-i2c.c b/drivers/iio/proximity/vl53l0x-i2c.c
index ad3e46d47..7acb94acc 100644
--- a/drivers/iio/proximity/vl53l0x-i2c.c
+++ b/drivers/iio/proximity/vl53l0x-i2c.c
@@ -87,15 +87,14 @@ static irqreturn_t vl53l0x_trigger_handler(int irq, void *priv)
 	ret = i2c_smbus_read_i2c_block_data(data->client,
 					VL_REG_RESULT_RANGE_STATUS,
 					sizeof(buffer), buffer);
-	if (ret < 0)
-		return ret;
-	else if (ret != 12)
-		return -EREMOTEIO;
+	if (ret < 0 || ret != 12)
+		goto done;
 
 	scan.chan = get_unaligned_be16(&buffer[10]);
 	iio_push_to_buffers_with_ts(indio_dev, &scan, sizeof(scan),
 				    iio_get_time_ns(indio_dev));
 
+done:
 	iio_trigger_notify_done(indio_dev->trig);
 	vl53l0x_clear_irq(data);
 
-- 
2.43.0