USB: add reset_resume method

This patch (as918) introduces a new USB driver method: reset_resume.
It is called when a device needs to be reset as part of a resume
procedure (whether because of a device quirk or because of the
USB-Persist facility), thereby taking over a role formerly assigned to
the post_reset method.  As a consequence, post_reset no longer needs
an argument indicating whether it is being called as part of a
reset-resume.  This separation of functions makes the code clearer.

In addition, the pre_reset and post_reset method return types are
changed; they now must return an error code.  The return value is
unused at present, but at some later time we may unbind drivers and
re-probe if they encounter an error during reset handling.

The existing pre_reset and post_reset methods in the usbhid,
usb-storage, and hub drivers are updated to match the new
requirements.  For usbhid the post_reset routine is also used for
reset_resume (duplicate method pointers); for the other drivers a new
reset_resume routine is added.  The change to hub.c looks bigger than
it really is, because mark_children_for_reset_resume() gets moved down
next to the new hub_reset_resume() routine.

A minor change to usb-storage makes the usb_stor_report_bus_reset()
routine acquire the host lock instead of requiring the caller to hold
it already.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index e221b0d1f667..b2baeaeba9be 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -1009,20 +1009,22 @@ static int hid_resume(struct usb_interface *intf)
 }
 
 /* Treat USB reset pretty much the same as suspend/resume */
-static void hid_pre_reset(struct usb_interface *intf)
+static int hid_pre_reset(struct usb_interface *intf)
 {
         /* FIXME: What if the interface is already suspended? */
         hid_suspend(intf, PMSG_ON);
+        return 0;
 }
 
-static void hid_post_reset(struct usb_interface *intf, int reset_resume)
+/* Same routine used for post_reset and reset_resume */
+static int hid_post_reset(struct usb_interface *intf)
 {
         struct usb_device *dev = interface_to_usbdev (intf);
 
         hid_set_idle(dev, intf->cur_altsetting->desc.bInterfaceNumber, 0, 0);
         /* FIXME: Any more reinitialization needed? */
 
-        hid_resume(intf);
+        return hid_resume(intf);
 }
 
 static struct usb_device_id hid_usb_ids [] = {
@@ -1039,6 +1041,7 @@ static struct usb_driver hid_driver = {
         .disconnect =   hid_disconnect,
         .suspend =      hid_suspend,
         .resume =       hid_resume,
+        .reset_resume = hid_post_reset,
         .pre_reset =    hid_pre_reset,
         .post_reset =   hid_post_reset,
         .id_table =     hid_usb_ids,