Commit b6f6436d authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

USB: move bus_suspend and bus_resume method calls 



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: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 4d461095

drivers/usb/core/driver.c

+5 −6
Original line number Diff line number Diff line
@@ -802,14 +802,13 @@ static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) 
			udev->state == USB_STATE_SUSPENDED)

		goto done;



	/* For devices that don't have a driver, we do a standard suspend. */

	if (udev->dev.driver == NULL) {

	/* For devices that don't have a driver, we do a generic suspend. */

	if (udev->dev.driver)

		udriver = to_usb_device_driver(udev->dev.driver);

	else {

		udev->do_remote_wakeup = 0;

		status = usb_port_suspend(udev);

		goto done;

		udriver = &usb_generic_driver;

	}



	udriver = to_usb_device_driver(udev->dev.driver);

	status = udriver->suspend(udev, msg);



done:

drivers/usb/core/generic.c

+37 −2
Original line number Diff line number Diff line
@@ -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 */

drivers/usb/core/hub.c

+1 −31
Original line number Diff line number Diff line
@@ -1916,7 +1916,6 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg) 
	struct usb_hub		*hub = usb_get_intfdata (intf);

	struct usb_device	*hdev = hub->hdev;

	unsigned		port1;

	int			status = 0;



	/* fail if children aren't already suspended */

	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
@@ -1942,44 +1941,15 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg) 


	/* stop khubd and related activity */

	hub_quiesce(hub);



	/* "global suspend" of the downstream HC-to-USB interface */

	if (!hdev->parent) {

		status = hcd_bus_suspend(hdev->bus);

		if (status != 0) {

			dev_dbg(&hdev->dev, "'global' suspend %d\n", status);

			hub_activate(hub);

		}

	}

	return status;

	return 0;

}



static int hub_resume(struct usb_interface *intf)

{

	struct usb_hub		*hub = usb_get_intfdata (intf);

	struct usb_device	*hdev = hub->hdev;

	int			status;



	dev_dbg(&intf->dev, "%s\n", __FUNCTION__);



	/* "global resume" of the downstream HC-to-USB interface */

	if (!hdev->parent) {

		struct usb_bus	*bus = hdev->bus;

		if (bus) {

			status = hcd_bus_resume (bus);

			if (status) {

				dev_dbg(&intf->dev, "'global' resume %d\n",

					status);

				return status;

			}

		} else

			return -EOPNOTSUPP;

		if (status == 0) {

			/* TRSMRCY = 10 msec */

			msleep(10);

		}

	}



	/* tell khubd to look for changes on this hub */

	hub_activate(hub);

	return 0;

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