From: Mike Lockwood <lockwood@android.com>
Date: Fri, 25 Mar 2011 19:22:22 +0000 (-0700)
Subject: USB: gadget: f_mtp: Don't block waiting for online state in read()
X-Git-Tag: firefly_0821_release~9834^2~32
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=89f57cb6b93c3ac3a3b46480574054e603c47c36;p=firefly-linux-kernel-4.4.55.git

USB: gadget: f_mtp: Don't block waiting for online state in read()

Return -ENODEV instead if USB is not connected.

Signed-off-by: Mike Lockwood <lockwood@android.com>
---

diff --git a/drivers/usb/gadget/f_mtp.c b/drivers/usb/gadget/f_mtp.c
index 92dd89b340bc..df6539fced25 100644
--- a/drivers/usb/gadget/f_mtp.c
+++ b/drivers/usb/gadget/f_mtp.c
@@ -469,15 +469,11 @@ static ssize_t mtp_read(struct file *fp, char __user *buf,
 	if (count > BULK_BUFFER_SIZE)
 		return -EINVAL;
 
-	/* we will block until we're online */
-	DBG(cdev, "mtp_read: waiting for online state\n");
-	ret = wait_event_interruptible(dev->read_wq,
-		dev->state != STATE_OFFLINE);
-	if (ret < 0) {
-		r = ret;
-		goto done;
-	}
 	spin_lock_irq(&dev->lock);
+	if (dev->state == STATE_OFFLINE) {
+		spin_unlock_irq(&dev->lock);
+		return -ENODEV;
+	}
 	if (dev->state == STATE_CANCELED) {
 		/* report cancelation to userspace */
 		dev->state = STATE_READY;