[PATCH] Input: charlieplex_keypad - check gpiod_direction_output() return value

[kr494167@gmail.com]

From: Surendra Singh Chouhan <kr494167@gmail.com>

charlieplex_keypad_scan_line() currently ignores the return value of
gpiod_direction_output() when setting the active output line for scanning.

If setting the GPIO direction fails (e.g. on I2C/SPI GPIO expanders or
hardware errors), the function continues to sleep and read input values
from an improperly configured GPIO line.

Fix this by capturing the return value of gpiod_direction_output() and
returning the error code immediately if it fails.

Fixes: 2ca45e57ea02 ("Input: charlieplex_keypad - add GPIO charlieplex keypad")
Signed-off-by: Surendra Singh Chouhan <kr494167@gmail.com>
---
 drivers/input/keyboard/charlieplex_keypad.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/input/keyboard/charlieplex_keypad.c b/drivers/input/keyboard/charlieplex_keypad.c
index d222b622c820..d46a2298e6da 100644
--- a/drivers/input/keyboard/charlieplex_keypad.c
+++ b/drivers/input/keyboard/charlieplex_keypad.c
@@ -77,7 +77,9 @@ static int charlieplex_keypad_scan_line(struct charlieplex_keypad *keypad,
 	int err;
 
 	/* Activate only one line as output at a time. */
-	gpiod_direction_output(line_gpios->desc[oline], 1);
+	err = gpiod_direction_output(line_gpios->desc[oline], 1);
+	if (err)
+		return err;
 
 	if (keypad->settling_time_us)
 		fsleep(keypad->settling_time_us);
-- 
2.55.0