Input: introduce input_inject_event() function

Create input_inject_event() function which is to be used by input
handlers as opposed to input_event() which is reserved for drivers
implementing input devices. The difference is that if device is
"grabbed" by some process input_inject_event() will ignore events
unless sent from the handle that is currently owns the device.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

4 files changed, 49 insertions, 21 deletions

diff --git a/drivers/char/keyboard.c b/drivers/char/keyboard.c
index 38de44b8750..1e946f58567 100644
--- a/drivers/char/keyboard.c
+++ b/drivers/char/keyboard.c
@@ -223,13 +223,13 @@ static void kd_nosound(unsigned long ignored)
 {
 	struct list_head *node;
 
-	list_for_each(node,&kbd_handler.h_list) {
+	list_for_each(node, &kbd_handler.h_list) {
 		struct input_handle *handle = to_handle_h(node);
 		if (test_bit(EV_SND, handle->dev->evbit)) {
 			if (test_bit(SND_TONE, handle->dev->sndbit))
-				input_event(handle->dev, EV_SND, SND_TONE, 0);
+				input_inject_event(handle, EV_SND, SND_TONE, 0);
 			if (test_bit(SND_BELL, handle->dev->sndbit))
-				input_event(handle->dev, EV_SND, SND_BELL, 0);
+				input_inject_event(handle, EV_SND, SND_BELL, 0);
 		}
 	}
 }
@@ -247,11 +247,11 @@ void kd_mksound(unsigned int hz, unsigned int ticks)
 			struct input_handle *handle = to_handle_h(node);
 			if (test_bit(EV_SND, handle->dev->evbit)) {
 				if (test_bit(SND_TONE, handle->dev->sndbit)) {
-					input_event(handle->dev, EV_SND, SND_TONE, hz);
+					input_inject_event(handle, EV_SND, SND_TONE, hz);
 					break;
 				}
 				if (test_bit(SND_BELL, handle->dev->sndbit)) {
-					input_event(handle->dev, EV_SND, SND_BELL, 1);
+					input_inject_event(handle, EV_SND, SND_BELL, 1);
 					break;
 				}
 			}
@@ -272,15 +272,15 @@ int kbd_rate(struct kbd_repeat *rep)
 	unsigned int d = 0;
 	unsigned int p = 0;
 
-	list_for_each(node,&kbd_handler.h_list) {
+	list_for_each(node, &kbd_handler.h_list) {
 		struct input_handle *handle = to_handle_h(node);
 		struct input_dev *dev = handle->dev;
 
 		if (test_bit(EV_REP, dev->evbit)) {
 			if (rep->delay > 0)
-				input_event(dev, EV_REP, REP_DELAY, rep->delay);
+				input_inject_event(handle, EV_REP, REP_DELAY, rep->delay);
 			if (rep->period > 0)
-				input_event(dev, EV_REP, REP_PERIOD, rep->period);
+				input_inject_event(handle, EV_REP, REP_PERIOD, rep->period);
 			d = dev->rep[REP_DELAY];
 			p = dev->rep[REP_PERIOD];
 		}
@@ -988,7 +988,7 @@ static inline unsigned char getleds(void)
  * interrupt routines for this thing allows us to easily mask
  * this when we don't want any of the above to happen.
  * This allows for easy and efficient race-condition prevention
- * for kbd_start => input_event(dev, EV_LED, ...) => ...
+ * for kbd_start => input_inject_event(dev, EV_LED, ...) => ...
  */
 
 static void kbd_bh(unsigned long dummy)
@@ -998,11 +998,11 @@ static void kbd_bh(unsigned long dummy)
 
 	if (leds != ledstate) {
 		list_for_each(node, &kbd_handler.h_list) {
-			struct input_handle * handle = to_handle_h(node);
-			input_event(handle->dev, EV_LED, LED_SCROLLL, !!(leds & 0x01));
-			input_event(handle->dev, EV_LED, LED_NUML,    !!(leds & 0x02));
-			input_event(handle->dev, EV_LED, LED_CAPSL,   !!(leds & 0x04));
-			input_sync(handle->dev);
+			struct input_handle *handle = to_handle_h(node);
+			input_inject_event(handle, EV_LED, LED_SCROLLL, !!(leds & 0x01));
+			input_inject_event(handle, EV_LED, LED_NUML,    !!(leds & 0x02));
+			input_inject_event(handle, EV_LED, LED_CAPSL,   !!(leds & 0x04));
+			input_inject_event(handle, EV_SYN, SYN_REPORT, 0);
 		}
 	}
 
@@ -1310,10 +1310,10 @@ static void kbd_start(struct input_handle *handle)
 
 	tasklet_disable(&keyboard_tasklet);
 	if (leds != 0xff) {
-		input_event(handle->dev, EV_LED, LED_SCROLLL, !!(leds & 0x01));
-		input_event(handle->dev, EV_LED, LED_NUML,    !!(leds & 0x02));
-		input_event(handle->dev, EV_LED, LED_CAPSL,   !!(leds & 0x04));
-		input_sync(handle->dev);
+		input_inject_event(handle, EV_LED, LED_SCROLLL, !!(leds & 0x01));
+		input_inject_event(handle, EV_LED, LED_NUML,    !!(leds & 0x02));
+		input_inject_event(handle, EV_LED, LED_CAPSL,   !!(leds & 0x04));
+		input_inject_event(handle, EV_SYN, SYN_REPORT, 0);
 	}
 	tasklet_enable(&keyboard_tasklet);
 }
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index 2426a5d8537..4bf48188cc9 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -256,7 +256,7 @@ static ssize_t evdev_write(struct file * file, const char __user * buffer, size_
 
 		if (evdev_event_from_user(buffer + retval, &event))
 			return -EFAULT;
-		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
+		input_inject_event(&list->evdev->handle, event.type, event.code, event.value);
 		retval += evdev_event_size();
 	}
 
@@ -424,8 +424,8 @@ static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
 			if (get_user(v, ip + 1))
 				return -EFAULT;
 
-			input_event(dev, EV_REP, REP_DELAY, u);
-			input_event(dev, EV_REP, REP_PERIOD, v);
+			input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
+			input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
 
 			return 0;
 
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 7aeebb9071c..e2091394292 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -35,6 +35,16 @@ static LIST_HEAD(input_handler_list);
 
 static struct input_handler *input_table[8];
 
+/**
+ * input_event() - report new input event
+ * @handle: device that generated the event
+ * @type: type of the event
+ * @code: event code
+ * @value: value of the event
+ *
+ * This function should be used by drivers implementing various input devices
+ * See also input_inject_event()
+ */
 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
 {
 	struct input_handle *handle;
@@ -183,6 +193,23 @@ void input_event(struct input_dev *dev, unsigned int type, unsigned int code, in
 }
 EXPORT_SYMBOL(input_event);
 
+/**
+ * input_inject_event() - send input event from input handler
+ * @handle: input handle to send event through
+ * @type: type of the event
+ * @code: event code
+ * @value: value of the event
+ *
+ * Similar to input_event() but will ignore event if device is "grabbed" and handle
+ * injecting event is not the one that owns the device.
+ */
+void input_inject_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
+{
+	if (!handle->dev->grab || handle->dev->grab == handle)
+		input_event(handle->dev, type, code, value);
+}
+EXPORT_SYMBOL(input_inject_event);
+
 static void input_repeat_key(unsigned long data)
 {
 	struct input_dev *dev = (void *) data;
diff --git a/include/linux/input.h b/include/linux/input.h
index 55e628e8805..b3253ab72ff 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -1053,6 +1053,7 @@ void input_close_device(struct input_handle *);
 int input_flush_device(struct input_handle* handle, struct file* file);
 
 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value);
+void input_inject_event(struct input_handle *handle, unsigned int type, unsigned int code, int value);
 
 static inline void input_report_key(struct input_dev *dev, unsigned int code, int value)
 {