[PATCH v2] Input: maple_keyb - use guard notation when acquiring mutex

From: Dmitry Torokhov
Date: Mon Oct 28 2024 - 01:50:44 EST


Using guard notation makes the code more compact and error handling
more robust by ensuring that mutexes are released in all code paths
when control leaves critical section.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---

v2: fix typo pointed out by the kernel test robot

drivers/input/keyboard/maple_keyb.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/input/keyboard/maple_keyb.c b/drivers/input/keyboard/maple_keyb.c
index 91a1d2958109..1a8f1fa53fbb 100644
--- a/drivers/input/keyboard/maple_keyb.c
+++ b/drivers/input/keyboard/maple_keyb.c
@@ -132,14 +132,11 @@ static void dc_kbd_callback(struct mapleq *mq)
* We should always get the lock because the only
* time it may be locked is if the driver is in the cleanup phase.
*/
- if (likely(mutex_trylock(&maple_keyb_mutex))) {
-
+ scoped_guard(mutex_try, &maple_keyb_mutex) {
if (buf[1] == mapledev->function) {
memcpy(kbd->new, buf + 2, 8);
dc_scan_kbd(kbd);
}
-
- mutex_unlock(&maple_keyb_mutex);
}
}

@@ -211,14 +208,12 @@ static int remove_maple_kbd(struct device *dev)
struct maple_device *mdev = to_maple_dev(dev);
struct dc_kbd *kbd = maple_get_drvdata(mdev);

- mutex_lock(&maple_keyb_mutex);
+ guard(mutex)(&maple_keyb_mutex);

input_unregister_device(kbd->dev);
kfree(kbd);

maple_set_drvdata(mdev, NULL);
-
- mutex_unlock(&maple_keyb_mutex);
return 0;
}


--
Dmitry