Commit 1f9fc882 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

OHCI: make autostop conditional on CONFIG_PM 



Unlike UHCI, OHCI does not exert any DMA load on the system when no
devices are connected.  Consequently there is no advantage to doing
an autostop other than the power savings, so we shouldn't compile the
necessary code unless CONFIG_PM is enabled.

This patch (as820) makes the root-hub suspend and resume routines
conditional on CONFIG_PM.  It also prevents autostop from activating
if the device_may_wakeup flag isn't set; some people use this flag to
alert the driver about Resume-Detect bugs in the hardware.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 40f122f3

drivers/usb/host/ohci-hub.c

+79 −54
Original line number Diff line number Diff line
@@ -56,7 +56,6 @@ static void finish_unlinks (struct ohci_hcd *, u16); 


#ifdef	CONFIG_PM

static int ohci_restart(struct ohci_hcd *ohci);

#endif



static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)

__releases(ohci->lock)
@@ -187,7 +186,6 @@ __acquires(ohci->lock) 
		ohci_dbg (ohci, "lost power\n");

		status = -EBUSY;

	}

#ifdef	CONFIG_PM

	if (status == -EBUSY) {

		if (!autostopped) {

			spin_unlock_irq (&ohci->lock);
@@ -197,7 +195,6 @@ __acquires(ohci->lock) 
		}

		return status;

	}

#endif

	if (status != -EINPROGRESS)

		return status;

	if (autostopped)
@@ -291,8 +288,6 @@ skip_resume: 
	return 0;

}



#ifdef	CONFIG_PM



static int ohci_bus_suspend (struct usb_hcd *hcd)

{

	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
@@ -330,6 +325,83 @@ static int ohci_bus_resume (struct usb_hcd *hcd) 
	return rc;

}



/* Carry out polling-, autostop-, and autoresume-related state changes */

static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,

		int any_connected)

{

	int	poll_rh = 1;



	switch (ohci->hc_control & OHCI_CTRL_HCFS) {



	case OHCI_USB_OPER:

		/* keep on polling until we know a device is connected

		 * and RHSC is enabled */

		if (!ohci->autostop) {

			if (any_connected ||

					!device_may_wakeup(&ohci_to_hcd(ohci)

						->self.root_hub->dev)) {

				if (ohci_readl(ohci, &ohci->regs->intrenable) &

						OHCI_INTR_RHSC)

					poll_rh = 0;

			} else {

				ohci->autostop = 1;

				ohci->next_statechange = jiffies + HZ;

			}



		/* if no devices have been attached for one second, autostop */

		} else {

			if (changed || any_connected) {

				ohci->autostop = 0;

				ohci->next_statechange = jiffies +

						STATECHANGE_DELAY;

			} else if (time_after_eq(jiffies,

						ohci->next_statechange)

					&& !ohci->ed_rm_list

					&& !(ohci->hc_control &

						OHCI_SCHED_ENABLES)) {

				ohci_rh_suspend(ohci, 1);

			}

		}

		break;



	/* if there is a port change, autostart or ask to be resumed */

	case OHCI_USB_SUSPEND:

	case OHCI_USB_RESUME:

		if (changed) {

			if (ohci->autostop)

				ohci_rh_resume(ohci);

			else

				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));

		} else {

			/* everything is idle, no need for polling */

			poll_rh = 0;

		}

		break;

	}

	return poll_rh;

}



#else	/* CONFIG_PM */



static inline int ohci_rh_resume(struct ohci_hcd *ohci)

{

	return 0;

}



/* Carry out polling-related state changes.

 * autostop isn't used when CONFIG_PM is turned off.

 */

static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,

		int any_connected)

{

	int	poll_rh = 1;



	/* keep on polling until RHSC is enabled */

	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)

		poll_rh = 0;

	return poll_rh;

}



#endif	/* CONFIG_PM */



/*-------------------------------------------------------------------------*/
@@ -382,55 +454,8 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf) 
		}

	}



	hcd->poll_rh = 1;



	/* carry out appropriate state changes */

	switch (ohci->hc_control & OHCI_CTRL_HCFS) {



	case OHCI_USB_OPER:

		/* keep on polling until we know a device is connected

		 * and RHSC is enabled */

		if (!ohci->autostop) {

			if (any_connected) {

				if (ohci_readl(ohci, &ohci->regs->intrenable) &

						OHCI_INTR_RHSC)

					hcd->poll_rh = 0;

			} else {

				ohci->autostop = 1;

				ohci->next_statechange = jiffies + HZ;

			}



		/* if no devices have been attached for one second, autostop */

		} else {

			if (changed || any_connected) {

				ohci->autostop = 0;

				ohci->next_statechange = jiffies +

						STATECHANGE_DELAY;

			} else if (device_may_wakeup(&hcd->self.root_hub->dev)

					&& time_after_eq(jiffies,

						ohci->next_statechange)

					&& !ohci->ed_rm_list

					&& !(ohci->hc_control &

						OHCI_SCHED_ENABLES)) {

				ohci_rh_suspend (ohci, 1);

			}

		}

		break;



	/* if there is a port change, autostart or ask to be resumed */

	case OHCI_USB_SUSPEND:

	case OHCI_USB_RESUME:

		if (changed) {

			if (ohci->autostop)

				ohci_rh_resume (ohci);

			else

				usb_hcd_resume_root_hub (hcd);

		} else {

			/* everything is idle, no need for polling */

			hcd->poll_rh = 0;

		}

		break;

	}

	hcd->poll_rh = ohci_root_hub_state_changes(ohci, changed,

			any_connected);



done:

	spin_unlock_irqrestore (&ohci->lock, flags);

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