From: Oliver Neukum <oliver@neukum.org>
Date: Wed, 25 Jun 2008 11:32:49 +0000 (+0200)
Subject: USB: fix usb serial pm counter decrement for disconnected interfaces
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=62ad296b6ca78bd123864c138814c0a597873693;p=openwrt%2Fstaging%2Fblogic.git

USB: fix usb serial pm counter decrement for disconnected interfaces

usb serial decrements the pm counter even if an interface has been
disconnected. If it was a logical disconnect the interface may belong
already to another driver. This patch introduces a check for disconnected
interfaces.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Cc: Stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 3bcf33466587..353798631903 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -283,7 +283,10 @@ static void serial_close(struct tty_struct *tty, struct file * filp)
 	}
 
 	if (port->open_count == 0) {
-		usb_autopm_put_interface(port->serial->interface);
+		mutex_lock(&port->serial->disc_mutex);
+		if (!port->serial->disconnected)
+			usb_autopm_put_interface(port->serial->interface);
+		mutex_unlock(&port->serial->disc_mutex);
 		module_put(port->serial->type->driver.owner);
 	}