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>
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 6c62a6d..3cd9af2 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -915,21 +915,37 @@
}
driver = to_usb_driver(intf->dev.driver);
- if (reset_resume && driver->post_reset)
- driver->post_reset(intf, reset_resume);
- else if (driver->resume) {
- status = driver->resume(intf);
- if (status)
- dev_err(&intf->dev, "%s error %d\n",
- "resume", status);
- } else
- dev_warn(&intf->dev, "no resume for driver %s?\n",
- driver->name);
+ if (reset_resume) {
+ if (driver->reset_resume) {
+ status = driver->reset_resume(intf);
+ if (status)
+ dev_err(&intf->dev, "%s error %d\n",
+ "reset_resume", status);
+ } else {
+ // status = -EOPNOTSUPP;
+ dev_warn(&intf->dev, "no %s for driver %s?\n",
+ "reset_resume", driver->name);
+ }
+ } else {
+ if (driver->resume) {
+ status = driver->resume(intf);
+ if (status)
+ dev_err(&intf->dev, "%s error %d\n",
+ "resume", status);
+ } else {
+ // status = -EOPNOTSUPP;
+ dev_warn(&intf->dev, "no %s for driver %s?\n",
+ "resume", driver->name);
+ }
+ }
done:
dev_vdbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
if (status == 0)
mark_active(intf);
+
+ /* FIXME: Unbind the driver and reprobe if the resume failed
+ * (not possible if auto_pm is set) */
return status;
}
@@ -966,6 +982,18 @@
"for autosuspend\n");
return -EOPNOTSUPP;
}
+
+ /* Don't allow autosuspend if the device will need
+ * a reset-resume and any of its interface drivers
+ * doesn't include support.
+ */
+ if (udev->quirks & USB_QUIRK_RESET_RESUME) {
+ struct usb_driver *driver;
+
+ driver = to_usb_driver(intf->dev.driver);
+ if (!driver->reset_resume)
+ return -EOPNOTSUPP;
+ }
}
}
@@ -1146,7 +1174,8 @@
status = usb_autoresume_device(parent);
if (status == 0) {
status = usb_resume_device(udev);
- if (status) {
+ if (status || udev->state ==
+ USB_STATE_NOTATTACHED) {
usb_autosuspend_device(parent);
/* It's possible usb_resume_device()