From 656acd2bbc4ce7f224de499ee255698701396c48 Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Thu, 26 Jun 2008 11:30:02 -0400
Subject: [PATCH] Input: fix locking in force-feedback core
The newly added event_lock spinlock in the input core disallows sleeping
and therefore using mutexes in event handlers. Convert force-feedback
core to rely on event_lock instead of mutex to protect slots allocated
for fore-feedback effects. The original mutex is still used to serialize
uploading and erasing of effects.
Reported-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
drivers/input/ff-core.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/drivers/input/ff-core.c b/drivers/input/ff-core.c
index eebc72465fc..4c01464ec8f 100644
--- a/drivers/input/ff-core.c
+++ b/drivers/input/ff-core.c
@@ -166,8 +166,10 @@ int input_ff_upload(struct input_dev *dev, struct ff_effect *effect,
if (ret)
goto out;
+ spin_lock_irq(&dev->event_lock);
ff->effects[id] = *effect;
ff->effect_owners[id] = file;
+ spin_unlock_irq(&dev->event_lock);
out:
mutex_unlock(&ff->mutex);
@@ -189,16 +191,22 @@ static int erase_effect(struct input_dev *dev, int effect_id,
if (error)
return error;
+ spin_lock_irq(&dev->event_lock);
ff->playback(dev, effect_id, 0);
+ ff->effect_owners[effect_id] = NULL;
+ spin_unlock_irq(&dev->event_lock);
if (ff->erase) {
error = ff->erase(dev, effect_id);
- if (error)
+ if (error) {
+ spin_lock_irq(&dev->event_lock);
+ ff->effect_owners[effect_id] = file;
+ spin_unlock_irq(&dev->event_lock);
+
return error;
+ }
}
- ff->effect_owners[effect_id] = NULL;
-
return 0;
}
@@ -263,8 +271,6 @@ int input_ff_event(struct input_dev *dev, unsigned int type,
if (type != EV_FF)
return 0;
- mutex_lock(&ff->mutex);
-
switch (code) {
case FF_GAIN:
if (!test_bit(FF_GAIN, dev->ffbit) || value > 0xffff)
@@ -286,7 +292,6 @@ int input_ff_event(struct input_dev *dev, unsigned int type,
break;
}
- mutex_unlock(&ff->mutex);
return 0;
}
EXPORT_SYMBOL_GPL(input_ff_event);
--
2.41.3