X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Finput%2Fevdev.c;h=f4897c8c15005ed943686e12ca3f022f24396933;hb=1474c71bcf2df2d45296aa936e7437998bd4785c;hp=c122dd2adc22bd16985cfea673132a4bff5b5c4c;hpb=244df97e7a9f8a3919c8684c061c565fe0f55f1d;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index c122dd2adc22..f4897c8c1500 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -26,6 +26,7 @@
 #include <linux/major.h>
 #include <linux/device.h>
 #include <linux/cdev.h>
+#include <linux/wakelock.h>
 #include "input-compat.h"
 
 struct evdev {
@@ -46,6 +47,9 @@ struct evdev_client {
 	unsigned int tail;
 	unsigned int packet_head; /* [future] position of the first element of next packet */
 	spinlock_t buffer_lock; /* protects access to buffer, head and tail */
+	struct wake_lock wake_lock;
+	bool use_wake_lock;
+	char name[28];
 	struct fasync_struct *fasync;
 	struct evdev *evdev;
 	struct list_head node;
@@ -73,10 +77,14 @@ static void __pass_event(struct evdev_client *client,
 		client->buffer[client->tail].value = 0;
 
 		client->packet_head = client->tail;
+		if (client->use_wake_lock)
+			wake_unlock(&client->wake_lock);
 	}
 
 	if (event->type == EV_SYN && event->code == SYN_REPORT) {
 		client->packet_head = client->head;
+		if (client->use_wake_lock)
+			wake_lock(&client->wake_lock);
 		kill_fasync(&client->fasync, SIGIO, POLL_IN);
 	}
 }
@@ -291,6 +299,8 @@ static int evdev_release(struct inode *inode, struct file *file)
 	mutex_unlock(&evdev->mutex);
 
 	evdev_detach_client(evdev, client);
+	if (client->use_wake_lock)
+		wake_lock_destroy(&client->wake_lock);
 
 	if (is_vmalloc_addr(client))
 		vfree(client);
@@ -328,6 +338,8 @@ static int evdev_open(struct inode *inode, struct file *file)
 
 	client->bufsize = bufsize;
 	spin_lock_init(&client->buffer_lock);
+	snprintf(client->name, sizeof(client->name), "%s-%d",
+			dev_name(&evdev->dev), task_tgid_vnr(current));
 	client->evdev = evdev;
 	evdev_attach_client(evdev, client);
 
@@ -394,6 +406,9 @@ static int evdev_fetch_next_event(struct evdev_client *client,
 	if (have_event) {
 		*event = client->buffer[client->tail++];
 		client->tail &= client->bufsize - 1;
+		if (client->use_wake_lock &&
+		    client->packet_head == client->tail)
+			wake_unlock(&client->wake_lock);
 	}
 
 	spin_unlock_irq(&client->buffer_lock);
@@ -682,6 +697,35 @@ static int evdev_handle_mt_request(struct input_dev *dev,
 	return 0;
 }
 
+static int evdev_enable_suspend_block(struct evdev *evdev,
+				      struct evdev_client *client)
+{
+	if (client->use_wake_lock)
+		return 0;
+
+	spin_lock_irq(&client->buffer_lock);
+	wake_lock_init(&client->wake_lock, WAKE_LOCK_SUSPEND, client->name);
+	client->use_wake_lock = true;
+	if (client->packet_head != client->tail)
+		wake_lock(&client->wake_lock);
+	spin_unlock_irq(&client->buffer_lock);
+	return 0;
+}
+
+static int evdev_disable_suspend_block(struct evdev *evdev,
+				       struct evdev_client *client)
+{
+	if (!client->use_wake_lock)
+		return 0;
+
+	spin_lock_irq(&client->buffer_lock);
+	client->use_wake_lock = false;
+	wake_lock_destroy(&client->wake_lock);
+	spin_unlock_irq(&client->buffer_lock);
+
+	return 0;
+}
+
 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
 			   void __user *p, int compat_mode)
 {
@@ -763,6 +807,15 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
 
 	case EVIOCSKEYCODE_V2:
 		return evdev_handle_set_keycode_v2(dev, p);
+
+	case EVIOCGSUSPENDBLOCK:
+		return put_user(client->use_wake_lock, ip);
+
+	case EVIOCSSUSPENDBLOCK:
+		if (p)
+			return evdev_enable_suspend_block(evdev, client);
+		else
+			return evdev_disable_suspend_block(evdev, client);
 	}
 
 	size = _IOC_SIZE(cmd);