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Input: rotary_encoder - use guard notation when acquiring mutex

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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.

Reviewed-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://lore.kernel.org/r/20240904044929.1049700-1-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Dmitry Torokhov 2024-09-03 21:49:29 -07:00
parent 2dc387620b
commit 868d163aec
1 changed files with 8 additions and 15 deletions
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23
drivers/input/misc/rotary_encoder.c
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@ -106,7 +106,7 @@ static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
struct rotary_encoder *encoder = dev_id;
unsigned int state;
mutex_lock(&encoder->access_mutex);
guard(mutex)(&encoder->access_mutex);
state = rotary_encoder_get_state(encoder);
@ -129,8 +129,6 @@ static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
break;
}
mutex_unlock(&encoder->access_mutex);
return IRQ_HANDLED;
}
@ -139,7 +137,7 @@ static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
struct rotary_encoder *encoder = dev_id;
unsigned int state;
mutex_lock(&encoder->access_mutex);
guard(mutex)(&encoder->access_mutex);
state = rotary_encoder_get_state(encoder);
@ -152,8 +150,6 @@ static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
}
}
mutex_unlock(&encoder->access_mutex);
return IRQ_HANDLED;
}
@ -162,22 +158,19 @@ static irqreturn_t rotary_encoder_quarter_period_irq(int irq, void *dev_id)
struct rotary_encoder *encoder = dev_id;
unsigned int state;
mutex_lock(&encoder->access_mutex);
guard(mutex)(&encoder->access_mutex);
state = rotary_encoder_get_state(encoder);
if ((encoder->last_stable + 1) % 4 == state)
if ((encoder->last_stable + 1) % 4 == state) {
encoder->dir = 1;
else if (encoder->last_stable == (state + 1) % 4)
rotary_encoder_report_event(encoder);
} else if (encoder->last_stable == (state + 1) % 4) {
encoder->dir = -1;
else
goto out;
rotary_encoder_report_event(encoder);
}
rotary_encoder_report_event(encoder);
out:
encoder->last_stable = state;
mutex_unlock(&encoder->access_mutex);
return IRQ_HANDLED;
}