From 10068a36b01dc25f598259ffd0562f474ae3ed94 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 3 Sep 2024 21:31:02 -0700 Subject: [PATCH] Input: turbografx - use guard notation when acquiring mutex 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. Link: https://lore.kernel.org/r/20240904043104.1030257-6-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov --- drivers/input/joystick/turbografx.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/drivers/input/joystick/turbografx.c b/drivers/input/joystick/turbografx.c index 0a78dda3e0ea..db696ba61a3b 100644 --- a/drivers/input/joystick/turbografx.c +++ b/drivers/input/joystick/turbografx.c @@ -103,33 +103,31 @@ static void tgfx_timer(struct timer_list *t) static int tgfx_open(struct input_dev *dev) { struct tgfx *tgfx = input_get_drvdata(dev); - int err; - err = mutex_lock_interruptible(&tgfx->sem); - if (err) - return err; + scoped_guard(mutex_intr, &tgfx->sem) { + if (!tgfx->used++) { + parport_claim(tgfx->pd); + parport_write_control(tgfx->pd->port, 0x04); + mod_timer(&tgfx->timer, jiffies + TGFX_REFRESH_TIME); + } - if (!tgfx->used++) { - parport_claim(tgfx->pd); - parport_write_control(tgfx->pd->port, 0x04); - mod_timer(&tgfx->timer, jiffies + TGFX_REFRESH_TIME); + return 0; } - mutex_unlock(&tgfx->sem); - return 0; + return -EINTR; } static void tgfx_close(struct input_dev *dev) { struct tgfx *tgfx = input_get_drvdata(dev); - mutex_lock(&tgfx->sem); + guard(mutex)(&tgfx->sem); + if (!--tgfx->used) { del_timer_sync(&tgfx->timer); parport_write_control(tgfx->pd->port, 0x00); parport_release(tgfx->pd); } - mutex_unlock(&tgfx->sem); } -- 2.50.1