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USB: move bus_suspend and bus_resume method calls

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This patch (as885) moves the root-hub bus_suspend() and bus_resume()
method calls from the hub driver's suspend and resume methods into the
usb_generic driver methods, where they make just as much sense.

Their old locations were not fully correct.  For example, in a kernel
compiled without CONFIG_USB_SUSPEND, if one were to do:

	echo -n 1-0:1.0 >/sys/bus/usb/drivers/hub/unbind

to unbind the hub driver from a root hub, there would then be no way
to suspend that root hub.  Attempts to put the system to sleep would
fail; the USB controller driver would refuse to suspend because the
root hub was still active.

The patch also makes a very slight change in the way devices with no
driver are handled during suspend.  Rather than doing a standard USB
port-suspend directly, now the suspend routine in usb_generic is
called.  In practice this should never affect anyone.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern
2007-05-04 11:51:54 -04:00
committed by Greg Kroah-Hartman
parent 4d461095ef
commit b6f6436da0
3 changed files with 43 additions and 39 deletions
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39
drivers/usb/core/generic.c
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@@ -19,6 +19,7 @@
#include <linux/usb.h>
#include "usb.h"
#include "hcd.h"
static inline const char *plural(int n)
{
@@ -193,12 +194,46 @@ static void generic_disconnect(struct usb_device *udev)
static int generic_suspend(struct usb_device *udev, pm_message_t msg)
{
return usb_port_suspend(udev);
int rc;
rc = usb_port_suspend(udev);
/* Root hubs don't have upstream ports to suspend,
* so the line above won't do much for them. We have to
* shut down their downstream HC-to-USB interfaces manually,
* by doing a bus (or "global") suspend.
*/
if (rc == 0 && !udev->parent) {
rc = hcd_bus_suspend(udev->bus);
if (rc) {
dev_dbg(&udev->dev, "'global' suspend %d\n", rc);
usb_port_resume(udev);
}
}
return rc;
}
static int generic_resume(struct usb_device *udev)
{
return usb_port_resume(udev);
int rc;
rc = usb_port_resume(udev);
/* Root hubs don't have upstream ports to resume or reset,
* so the line above won't do much for them. We have to
* start up their downstream HC-to-USB interfaces manually,
* by doing a bus (or "global") resume.
*/
if (rc == 0 && !udev->parent) {
rc = hcd_bus_resume(udev->bus);
if (rc)
dev_dbg(&udev->dev, "'global' resume %d\n", rc);
else {
/* TRSMRCY = 10 msec */
msleep(10);
}
}
return rc;
}
#endif /* CONFIG_PM */