Linux-libre 4.6.2-gnu

1 files changed, 25 insertions, 23 deletions

diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
index 1042fa331..4e9bbe735 100644
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -13,6 +13,7 @@
  */
 
 #include <media/rc-core.h>
+#include <linux/atomic.h>
 #include <linux/spinlock.h>
 #include <linux/delay.h>
 #include <linux/input.h>
@@ -723,6 +724,7 @@ int rc_open(struct rc_dev *rdev)
 		return -EINVAL;
 
 	mutex_lock(&rdev->lock);
+
 	if (!rdev->users++ && rdev->open != NULL)
 		rval = rdev->open(rdev);
 
@@ -873,6 +875,9 @@ static ssize_t show_protocols(struct device *device,
 	if (!dev)
 		return -EINVAL;
 
+	if (!atomic_read(&dev->initialized))
+		return -ERESTARTSYS;
+
 	mutex_lock(&dev->lock);
 
 	if (fattr->type == RC_FILTER_NORMAL) {
@@ -1054,6 +1059,9 @@ static ssize_t store_protocols(struct device *device,
 	if (!dev)
 		return -EINVAL;
 
+	if (!atomic_read(&dev->initialized))
+		return -ERESTARTSYS;
+
 	if (fattr->type == RC_FILTER_NORMAL) {
 		IR_dprintk(1, "Normal protocol change requested\n");
 		current_protocols = &dev->enabled_protocols;
@@ -1154,12 +1162,16 @@ static ssize_t show_filter(struct device *device,
 	if (!dev)
 		return -EINVAL;
 
+	if (!atomic_read(&dev->initialized))
+		return -ERESTARTSYS;
+
+	mutex_lock(&dev->lock);
+
 	if (fattr->type == RC_FILTER_NORMAL)
 		filter = &dev->scancode_filter;
 	else
 		filter = &dev->scancode_wakeup_filter;
 
-	mutex_lock(&dev->lock);
 	if (fattr->mask)
 		val = filter->mask;
 	else
@@ -1204,6 +1216,9 @@ static ssize_t store_filter(struct device *device,
 	if (!dev)
 		return -EINVAL;
 
+	if (!atomic_read(&dev->initialized))
+		return -ERESTARTSYS;
+
 	ret = kstrtoul(buf, 0, &val);
 	if (ret < 0)
 		return ret;
@@ -1408,6 +1423,7 @@ int rc_register_device(struct rc_dev *dev)
 	dev->minor = minor;
 	dev_set_name(&dev->dev, "rc%u", dev->minor);
 	dev_set_drvdata(&dev->dev, dev);
+	atomic_set(&dev->initialized, 0);
 
 	dev->dev.groups = dev->sysfs_groups;
 	dev->sysfs_groups[attr++] = &rc_dev_protocol_attr_grp;
@@ -1419,14 +1435,6 @@ int rc_register_device(struct rc_dev *dev)
 		dev->sysfs_groups[attr++] = &rc_dev_wakeup_protocol_attr_grp;
 	dev->sysfs_groups[attr++] = NULL;
 
-	/*
-	 * Take the lock here, as the device sysfs node will appear
-	 * when device_add() is called, which may trigger an ir-keytable udev
-	 * rule, which will in turn call show_protocols and access
-	 * dev->enabled_protocols before it has been initialized.
-	 */
-	mutex_lock(&dev->lock);
-
 	rc = device_add(&dev->dev);
 	if (rc)
 		goto out_unlock;
@@ -1440,16 +1448,6 @@ int rc_register_device(struct rc_dev *dev)
 	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;
-
 	/*
 	 * Default delay of 250ms is too short for some protocols, especially
 	 * since the timeout is currently set to 250ms. Increase it to 500ms,
@@ -1465,6 +1463,11 @@ int rc_register_device(struct rc_dev *dev)
 	 */
 	dev->input_dev->rep[REP_PERIOD] = 125;
 
+	/* rc_open will be called here */
+	rc = input_register_device(dev->input_dev);
+	if (rc)
+		goto out_table;
+
 	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
 	dev_info(&dev->dev, "%s as %s\n",
 		dev->input_name ?: "Unspecified device", path ?: "N/A");
@@ -1475,10 +1478,7 @@ int rc_register_device(struct rc_dev *dev)
 			request_module_nowait("ir-lirc-codec");
 			raw_init = true;
 		}
-		/* calls ir_register_device so unlock mutex here*/
-		mutex_unlock(&dev->lock);
 		rc = ir_raw_event_register(dev);
-		mutex_lock(&dev->lock);
 		if (rc < 0)
 			goto out_input;
 	}
@@ -1491,6 +1491,9 @@ int rc_register_device(struct rc_dev *dev)
 		dev->enabled_protocols = rc_type;
 	}
 
+	/* Allow the RC sysfs nodes to be accessible */
+	mutex_lock(&dev->lock);
+	atomic_set(&dev->initialized, 1);
 	mutex_unlock(&dev->lock);
 
 	IR_dprintk(1, "Registered rc%u (driver: %s, remote: %s, mode %s)\n",
@@ -1512,7 +1515,6 @@ out_table:
 out_dev:
 	device_del(&dev->dev);
 out_unlock:
-	mutex_unlock(&dev->lock);
 	ida_simple_remove(&rc_ida, minor);
 	return rc;
 }