Commit 5c54fcac authored by Heikki Krogerus's avatar Heikki Krogerus Committed by Greg Kroah-Hartman

usb: roles: Take care of driver module reference counting

This fixes potential "BUG: unable to handle kernel paging
request at ..." from happening.

Fixes: fde0aa6c ("usb: common: Small class for USB role switches")
Cc: <stable@vger.kernel.org>
Acked-by: default avatarHans de Goede <hdegoede@redhat.com>
Tested-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c9a4cb20
...@@ -109,8 +109,15 @@ static void *usb_role_switch_match(struct device_connection *con, int ep, ...@@ -109,8 +109,15 @@ static void *usb_role_switch_match(struct device_connection *con, int ep,
*/ */
struct usb_role_switch *usb_role_switch_get(struct device *dev) struct usb_role_switch *usb_role_switch_get(struct device *dev)
{ {
return device_connection_find_match(dev, "usb-role-switch", NULL, struct usb_role_switch *sw;
sw = device_connection_find_match(dev, "usb-role-switch", NULL,
usb_role_switch_match); usb_role_switch_match);
if (!IS_ERR_OR_NULL(sw))
WARN_ON(!try_module_get(sw->dev.parent->driver->owner));
return sw;
} }
EXPORT_SYMBOL_GPL(usb_role_switch_get); EXPORT_SYMBOL_GPL(usb_role_switch_get);
...@@ -122,8 +129,10 @@ EXPORT_SYMBOL_GPL(usb_role_switch_get); ...@@ -122,8 +129,10 @@ EXPORT_SYMBOL_GPL(usb_role_switch_get);
*/ */
void usb_role_switch_put(struct usb_role_switch *sw) void usb_role_switch_put(struct usb_role_switch *sw)
{ {
if (!IS_ERR_OR_NULL(sw)) if (!IS_ERR_OR_NULL(sw)) {
put_device(&sw->dev); put_device(&sw->dev);
module_put(sw->dev.parent->driver->owner);
}
} }
EXPORT_SYMBOL_GPL(usb_role_switch_put); EXPORT_SYMBOL_GPL(usb_role_switch_put);
......
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