[media] media: rc: Add rc_open/close and use count to rc_dev

This patch adds user count to rc_dev structure, the reason to add this
new member is to allow other code like lirc to open rc device directly.
In the existing code, rc device is only opened by input subsystem which
works ok if we have any input drivers to match. But in case like lirc
where there will be no input driver, rc device will be never opened.
Having this user count variable will be usefull to allow rc device to be
opened from code other than rc-main.
This patch also adds rc_open and rc_close functions for other drivers
like lirc to open and close rc devices. This functions safely increment
and decrement the user count. Other driver wanting to open rc device
should call rc_open and rc_close, rather than directly modifying the
rc_dev structure.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
index 1cf382a0b27761683f6afa4d8c07aed3904ed789..1dedebda1cefb6fd9e11364ebad36cb60ab1fbb5 100644 (file)
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -699,19 +699,50 @@ void rc_keydown_notimeout(struct rc_dev *dev, int scancode, u8 toggle)
 }
 EXPORT_SYMBOL_GPL(rc_keydown_notimeout);
 
+int rc_open(struct rc_dev *rdev)
+{
+       int rval = 0;
+
+       if (!rdev)
+               return -EINVAL;
+
+       mutex_lock(&rdev->lock);
+       if (!rdev->users++)
+               rval = rdev->open(rdev);
+
+       if (rval)
+               rdev->users--;
+
+       mutex_unlock(&rdev->lock);
+
+       return rval;
+}
+EXPORT_SYMBOL_GPL(rc_open);
+
 static int ir_open(struct input_dev *idev)
 {
        struct rc_dev *rdev = input_get_drvdata(idev);
 
-       return rdev->open(rdev);
+       return rc_open(rdev);
+}
+
+void rc_close(struct rc_dev *rdev)
+{
+       if (rdev) {
+               mutex_lock(&rdev->lock);
+
+                if (!--rdev->users)
+                       rdev->close(rdev);
+
+               mutex_unlock(&rdev->lock);
+       }
 }
+EXPORT_SYMBOL_GPL(rc_close);
 
 static void ir_close(struct input_dev *idev)
 {
        struct rc_dev *rdev = input_get_drvdata(idev);
-
-        if (rdev)
-               rdev->close(rdev);
+       rc_close(rdev);
 }
 
 /* class for /sys/class/rc */
@@ -1076,7 +1107,14 @@ int rc_register_device(struct rc_dev *dev)
        memcpy(&dev->input_dev->id, &dev->input_id, sizeof(dev->input_id));
        dev->input_dev->phys = dev->input_phys;
        dev->input_dev->name = dev->input_name;
+
+       /* input_register_device can call ir_open, so unlock mutex here */
+       mutex_unlock(&dev->lock);
+
        rc = input_register_device(dev->input_dev);
+
+       mutex_lock(&dev->lock);
+
        if (rc)
                goto out_table;
 

diff --git a/include/media/rc-core.h b/include/media/rc-core.h
index 06a75deff553c4a2fac3396c48b3954dda422432..2f6f1f78d958c5238e3f0a145c0c33c0a38b45f0 100644 (file)
--- a/include/media/rc-core.h
+++ b/include/media/rc-core.h
@@ -101,6 +101,7 @@ struct rc_dev {
        bool                            idle;
        u64                             allowed_protos;
        u64                             enabled_protocols;
+       u32                             users;
        u32                             scanmask;
        void                            *priv;
        spinlock_t                      keylock;
@@ -142,6 +143,9 @@ void rc_free_device(struct rc_dev *dev);
 int rc_register_device(struct rc_dev *dev);
 void rc_unregister_device(struct rc_dev *dev);
 
+int rc_open(struct rc_dev *rdev);
+void rc_close(struct rc_dev *rdev);
+
 void rc_repeat(struct rc_dev *dev);
 void rc_keydown(struct rc_dev *dev, int scancode, u8 toggle);
 void rc_keydown_notimeout(struct rc_dev *dev, int scancode, u8 toggle);