diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2008-12-31 11:31:33 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-01-07 10:00:13 -0800 |
| commit | 2caf7fcdb8532045680f06b67b9e63f0c9613aaa (patch) | |
| tree | d9faee328532a3badd73d20e175259e8bdea271a /drivers/usb/core/driver.c | |
| parent | df718962bf91c7bd345060aadaa24b03f6140b07 (diff) | |
USB: re-enable interface after driver unbinds
This patch (as1197) fixes an error introduced recently. Since a
significant number of devices can't handle Set-Interface requests, we
no longer call usb_set_interface() when a driver unbinds from an
interface, provided the interface is already in altsetting 0. However
the interface still does get disabled, and the call to
usb_set_interface() was the only thing re-enabling it. Since the
interface doesn't get re-enabled, further attempts to use it fail.
So the patch adds a call to usb_enable_interface() when a driver
unbinds and the interface is in altsetting 0. For this to work
right, the interface's endpoints have to be re-enabled but their
toggles have to be left alone. Therefore an additional argument is
added to usb_enable_endpoint() and usb_enable_interface(), a flag
indicating whether or not the endpoint toggles should be reset.
This is a forward-ported version of a patch which fixes Bugzilla
#12301.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: David Roka <roka@dawid.hu>
Reported-by: Erik Ekman <erik@kryo.se>
Tested-by: Erik Ekman <erik@kryo.se>
Tested-by: Alon Bar-Lev <alon.barlev@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/core/driver.c')
| -rw-r--r-- | drivers/usb/core/driver.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 41c06025506..98760553bc9 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -295,9 +295,12 @@ static int usb_unbind_interface(struct device *dev) * altsetting means creating new endpoint device entries). * When either of these happens, defer the Set-Interface. */ - if (intf->cur_altsetting->desc.bAlternateSetting == 0) - ; /* Already in altsetting 0 so skip Set-Interface */ - else if (!error && intf->dev.power.status == DPM_ON) + if (intf->cur_altsetting->desc.bAlternateSetting == 0) { + /* Already in altsetting 0 so skip Set-Interface. + * Just re-enable it without affecting the endpoint toggles. + */ + usb_enable_interface(udev, intf, false); + } else if (!error && intf->dev.power.status == DPM_ON) usb_set_interface(udev, intf->altsetting[0]. desc.bInterfaceNumber, 0); else |