[PATCH] misc: lis3lv02d: Handle click source read errors

The threaded click handler ignores the status returned when reading
CLICK_SRC. With the SPI transport, spi_w8r8() can fail without storing
anything in the output byte. The handler then tests an uninitialized
click_src and can report spurious axis button events.

Check the read status and skip the event when CLICK_SRC cannot be
fetched. Exit through the common unlock path so successful event
handling and mutex coverage remain unchanged.

This issue was found by a static analysis checker and confirmed by
manual source review.

Fixes: 6d94d4081048 ("lis3: interrupt handlers for 8bit wakeup and click events")
Signed-off-by: Ruoyu Wang <[email protected]>
---
 drivers/misc/lis3lv02d/lis3lv02d.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/lis3lv02d/lis3lv02d.c b/drivers/misc/lis3lv02d/lis3lv02d.c
index 21e8ad0a74442..450a0bf15bdcd 100644
--- a/drivers/misc/lis3lv02d/lis3lv02d.c
+++ b/drivers/misc/lis3lv02d/lis3lv02d.c
@@ -511,7 +511,8 @@ static void lis302dl_interrupt_handle_click(struct lis3lv02d *lis3)
 	u8 click_src;
 
 	mutex_lock(&lis3->mutex);
-	lis3->read(lis3, CLICK_SRC, &click_src);
+	if (lis3->read(lis3, CLICK_SRC, &click_src) < 0)
+		goto out;
 
 	if (click_src & CLICK_SINGLE_X) {
 		input_report_key(dev, lis3->mapped_btns[0], 1);
@@ -528,6 +529,7 @@ static void lis302dl_interrupt_handle_click(struct lis3lv02d *lis3)
 		input_report_key(dev, lis3->mapped_btns[2], 0);
 	}
 	input_sync(dev);
+out:
 	mutex_unlock(&lis3->mutex);
 }
 
-- 
2.51.0