1 files changed, 61 insertions, 20 deletions

diff --git a/drivers/usb/misc/chaoskey.c b/drivers/usb/misc/chaoskey.c
index cf5828ce927a..45cff32656c6 100644
--- a/drivers/usb/misc/chaoskey.c
+++ b/drivers/usb/misc/chaoskey.c
@@ -27,6 +27,8 @@ static struct usb_class_driver chaoskey_class;
 static int chaoskey_rng_read(struct hwrng *rng, void *data,
 			     size_t max, bool wait);
 
+static DEFINE_MUTEX(chaoskey_list_lock);
+
 #define usb_dbg(usb_if, format, arg...) \
 	dev_dbg(&(usb_if)->dev, format, ## arg)
 
@@ -98,6 +100,7 @@ static void chaoskey_free(struct chaoskey *dev)
 		usb_free_urb(dev->urb);
 		kfree(dev->name);
 		kfree(dev->buf);
+		usb_put_intf(dev->interface);
 		kfree(dev);
 	}
 }
@@ -145,6 +148,8 @@ static int chaoskey_probe(struct usb_interface *interface,
 	if (dev == NULL)
 		goto out;
 
+	dev->interface = usb_get_intf(interface);
+
 	dev->buf = kmalloc(size, GFP_KERNEL);
 
 	if (dev->buf == NULL)
@@ -174,8 +179,6 @@ static int chaoskey_probe(struct usb_interface *interface,
 			goto out;
 	}
 
-	dev->interface = interface;
-
 	dev->in_ep = in_ep;
 
 	if (le16_to_cpu(udev->descriptor.idVendor) != ALEA_VENDOR_ID)
@@ -199,7 +202,6 @@ static int chaoskey_probe(struct usb_interface *interface,
 
 	dev->hwrng.name = dev->name ? dev->name : chaoskey_driver.name;
 	dev->hwrng.read = chaoskey_rng_read;
-	dev->hwrng.quality = 1024;
 
 	dev->hwrng_registered = (hwrng_register(&dev->hwrng) == 0);
 	if (!dev->hwrng_registered)
@@ -233,6 +235,7 @@ static void chaoskey_disconnect(struct usb_interface *interface)
 	usb_deregister_dev(interface, &chaoskey_class);
 
 	usb_set_intfdata(interface, NULL);
+	mutex_lock(&chaoskey_list_lock);
 	mutex_lock(&dev->lock);
 
 	dev->present = false;
@@ -244,6 +247,7 @@ static void chaoskey_disconnect(struct usb_interface *interface)
 	} else
 		mutex_unlock(&dev->lock);
 
+	mutex_unlock(&chaoskey_list_lock);
 	usb_dbg(interface, "disconnect done");
 }
 
@@ -251,6 +255,7 @@ static int chaoskey_open(struct inode *inode, struct file *file)
 {
 	struct chaoskey *dev;
 	struct usb_interface *interface;
+	int rv = 0;
 
 	/* get the interface from minor number and driver information */
 	interface = usb_find_interface(&chaoskey_driver, iminor(inode));
@@ -266,18 +271,23 @@ static int chaoskey_open(struct inode *inode, struct file *file)
 	}
 
 	file->private_data = dev;
+	mutex_lock(&chaoskey_list_lock);
 	mutex_lock(&dev->lock);
-	++dev->open;
+	if (dev->present)
+		++dev->open;
+	else
+		rv = -ENODEV;
 	mutex_unlock(&dev->lock);
+	mutex_unlock(&chaoskey_list_lock);
 
-	usb_dbg(interface, "open success");
-	return 0;
+	return rv;
 }
 
 static int chaoskey_release(struct inode *inode, struct file *file)
 {
 	struct chaoskey *dev = file->private_data;
 	struct usb_interface *interface;
+	int rv = 0;
 
 	if (dev == NULL)
 		return -ENODEV;
@@ -286,14 +296,15 @@ static int chaoskey_release(struct inode *inode, struct file *file)
 
 	usb_dbg(interface, "release");
 
+	mutex_lock(&chaoskey_list_lock);
 	mutex_lock(&dev->lock);
 
 	usb_dbg(interface, "open count at release is %d", dev->open);
 
 	if (dev->open <= 0) {
 		usb_dbg(interface, "invalid open count (%d)", dev->open);
-		mutex_unlock(&dev->lock);
-		return -ENODEV;
+		rv = -ENODEV;
+		goto bail;
 	}
 
 	--dev->open;
@@ -302,13 +313,15 @@ static int chaoskey_release(struct inode *inode, struct file *file)
 		if (dev->open == 0) {
 			mutex_unlock(&dev->lock);
 			chaoskey_free(dev);
-		} else
-			mutex_unlock(&dev->lock);
-	} else
-		mutex_unlock(&dev->lock);
-
+			goto destruction;
+		}
+	}
+bail:
+	mutex_unlock(&dev->lock);
+destruction:
+	mutex_unlock(&chaoskey_list_lock);
 	usb_dbg(interface, "release success");
-	return 0;
+	return rv;
 }
 
 static void chaos_read_callback(struct urb *urb)
@@ -383,13 +396,17 @@ static int _chaoskey_fill(struct chaoskey *dev)
 		!dev->reading,
 		(started ? NAK_TIMEOUT : ALEA_FIRST_TIMEOUT) );
 
-	if (result < 0)
+	if (result < 0) {
+		usb_kill_urb(dev->urb);
 		goto out;
+	}
 
-	if (result == 0)
+	if (result == 0) {
 		result = -ETIMEDOUT;
-	else
+		usb_kill_urb(dev->urb);
+	} else {
 		result = dev->valid;
+	}
 out:
 	/* Let the device go back to sleep eventually */
 	usb_autopm_put_interface(dev->interface);
@@ -427,9 +444,19 @@ static ssize_t chaoskey_read(struct file *file,
 			goto bail;
 		mutex_unlock(&dev->rng_lock);
 
-		result = mutex_lock_interruptible(&dev->lock);
-		if (result)
-			goto bail;
+		if (file->f_flags & O_NONBLOCK) {
+			result = mutex_trylock(&dev->lock);
+			if (result == 0) {
+				result = -EAGAIN;
+				goto bail;
+			} else {
+				result = 0;
+			}
+		} else {
+			result = mutex_lock_interruptible(&dev->lock);
+			if (result)
+				goto bail;
+		}
 		if (dev->valid == dev->used) {
 			result = _chaoskey_fill(dev);
 			if (result < 0) {
@@ -525,7 +552,21 @@ static int chaoskey_suspend(struct usb_interface *interface,
 
 static int chaoskey_resume(struct usb_interface *interface)
 {
+	struct chaoskey *dev;
+	struct usb_device *udev = interface_to_usbdev(interface);
+
 	usb_dbg(interface, "resume");
+	dev = usb_get_intfdata(interface);
+
+	/*
+	 * We may have lost power.
+	 * In that case the device that needs a long time
+	 * for the first requests needs an extended timeout
+	 * again
+	 */
+	if (le16_to_cpu(udev->descriptor.idVendor) == ALEA_VENDOR_ID)
+		dev->reads_started = false;
+
 	return 0;
 }
 #else