USB: fix autosuspend bug in usb-serial

This patch (as1437) fixes a bug in the usb-serial autosuspend
handling.  Since the usb-serial core now has autosuspend support, it
must set the .supports_autosuspend member in every serial driver it
registers.  Otherwise the usb_autopm_get_interface() call won't work.

This fixes Bugzilla #23012.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: stable@kernel.org
Reported-by: Kevin Smith <thirdwiggin@gmail.com>
Reported-and-tested-by: Simon Gerber <gesimu@gmail.com>
Reported-and-tested-by: Matteo Croce <matteo@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 861223f2af6e..6954de50c0ff 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -51,6 +51,7 @@ static struct usb_driver usb_serial_driver = {
         .suspend =      usb_serial_suspend,
         .resume =       usb_serial_resume,
         .no_dynamic_id =        1,
+        .supports_autosuspend = 1,
 };
 
 /* There is no MODULE_DEVICE_TABLE for usbserial.c.  Instead
@@ -1343,6 +1344,8 @@ int usb_serial_register(struct usb_serial_driver *driver)
                 return -ENODEV;
 
         fixup_generic(driver);
+        if (driver->usb_driver)
+                driver->usb_driver->supports_autosuspend = 1;
 
         if (!driver->description)
                 driver->description = driver->driver.name;