USB hub: simplify remote-wakeup handling

This patch (as817) simplifies the remote-wakeup processing in the hub
driver.  Now instead of using a specialized code path, it relies on
the standard USB resume routines.  The hub_port_resume() function does
an initial get_port_status() to see whether the port has already
resumed itself (as it does when a remote-wakeup request is sent).
This will slow down handling of other resume events slightly, but not
enough to matter.

The patch also changes the hub_port_status() routine, making it return
an error if a short reply is received.

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 2006-11-20 11:14:30 -05:00 committed by Greg Kroah-Hartman
parent ce3615879a
commit d25450c687

View file

@ -1409,10 +1409,12 @@ static int hub_port_status(struct usb_hub *hub, int port1,
int ret;
ret = get_port_status(hub->hdev, port1, &hub->status->port);
if (ret < 0)
if (ret < 4) {
dev_err (hub->intfdev,
"%s failed (err = %d)\n", __FUNCTION__, ret);
else {
if (ret >= 0)
ret = -EIO;
} else {
*status = le16_to_cpu(hub->status->port.wPortStatus);
*change = le16_to_cpu(hub->status->port.wPortChange);
ret = 0;
@ -1760,6 +1762,12 @@ static int
hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
{
int status;
u16 portchange, portstatus;
/* Skip the initial Clear-Suspend step for a remote wakeup */
status = hub_port_status(hub, port1, &portstatus, &portchange);
if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
goto SuspendCleared;
// dev_dbg(hub->intfdev, "resume port %d\n", port1);
@ -1773,9 +1781,6 @@ hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
"can't resume port %d, status %d\n",
port1, status);
} else {
u16 devstatus;
u16 portchange;
/* drive resume for at least 20 msec */
if (udev)
dev_dbg(&udev->dev, "usb %sresume\n",
@ -1790,16 +1795,15 @@ hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
* stop resume signaling. Then finish the resume
* sequence.
*/
devstatus = portchange = 0;
status = hub_port_status(hub, port1,
&devstatus, &portchange);
status = hub_port_status(hub, port1, &portstatus, &portchange);
SuspendCleared:
if (status < 0
|| (devstatus & LIVE_FLAGS) != LIVE_FLAGS
|| (devstatus & USB_PORT_STAT_SUSPEND) != 0
|| (portstatus & LIVE_FLAGS) != LIVE_FLAGS
|| (portstatus & USB_PORT_STAT_SUSPEND) != 0
) {
dev_dbg(hub->intfdev,
"port %d status %04x.%04x after resume, %d\n",
port1, portchange, devstatus, status);
port1, portchange, portstatus, status);
if (status >= 0)
status = -ENODEV;
} else {
@ -1860,23 +1864,16 @@ static int remote_wakeup(struct usb_device *udev)
{
int status = 0;
/* All this just to avoid sending a port-resume message
* to the parent hub! */
usb_lock_device(udev);
usb_pm_lock(udev);
if (udev->state == USB_STATE_SUSPENDED) {
dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
/* TRSMRCY = 10 msec */
msleep(10);
status = finish_port_resume(udev);
if (status == 0)
udev->dev.power.power_state.event = PM_EVENT_ON;
}
usb_pm_unlock(udev);
status = usb_autoresume_device(udev, 1);
if (status == 0)
usb_autoresume_device(udev, 0);
/* Give the interface drivers a chance to do something,
* then autosuspend the device again. */
if (status == 0)
usb_autosuspend_device(udev, 1);
}
usb_unlock_device(udev);
return status;
}