Re: [patch]bug in error path in new autosuspend code
Alan Stern <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
On Mon, 19 Feb 2007, Oliver Neukum wrote: > Hi Alan, > > if probe() fails, you fail to restore the old pm count. If the driver > supports autosuspend, but doesn't bind, the interface, though unbound, > will not suspend again. > > Regards > Oliver > > Signed-off-by: Oliver Neukum <[email protected]> > ------ > > --- a/drivers/usb/core/driver.c 2007-02-19 14:27:11.000000000 +0100 > +++ b/drivers/usb/core/driver.c 2007-02-19 14:32:13.000000000 +0100 > @@ -189,6 +189,7 @@ > struct usb_interface *intf; > struct usb_device *udev; > const struct usb_device_id *id; > + int old_usage_count; > int error = -ENODEV; > > dev_dbg(dev, "%s\n", __FUNCTION__); > @@ -219,12 +220,14 @@ > /* The interface should always appear to be in use > * unless the driver suports autosuspend. > */ > + old_usage_count = intf->pm_usage_cnt; > intf->pm_usage_cnt = !(driver->supports_autosuspend); > > error = driver->probe(intf, id); > if (error) { > mark_quiesced(intf); > intf->needs_remote_wakeup = 0; > + intf->pm_usage_cnt = old_usage_count; > intf->condition = USB_INTERFACE_UNBOUND; > } else > intf->condition = USB_INTERFACE_BOUND; This change isn't needed. The fact that mark_quiesced() is called for the interface means that the pm_usage_cnt won't be used for anything -- until another driver is probed. After all, if no driver is bound to the interface then the pm_usage_cnt value is meaningless. By definition, the interface cannot be in use. Alan Stern ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel