Commit a448e4dc authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

EHCI: keep track of ports being resumed and indicate in hub_status_data 



This patch (as1537) adds a bit-array to ehci-hcd for keeping track of
which ports are undergoing a resume transition.  If any of the bits
are set when ehci_hub_status_data() is called, the routine will return
a nonzero value even if no ports have any status changes pending.
This will allow usbcore to handle races between root-hub suspend and
port wakeup.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
CC: Chen Peter-B29397 <B29397@freescale.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 879d38e6

drivers/usb/host/ehci-hcd.c

+3 −0
Original line number Diff line number Diff line
@@ -347,6 +347,8 @@ static int ehci_reset (struct ehci_hcd *ehci) 
	if (ehci->debug)

		dbgp_external_startup();



	ehci->port_c_suspend = ehci->suspended_ports =

			ehci->resuming_ports = 0;

	return retval;

}
@@ -939,6 +941,7 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd) 
			 * like usb_port_resume() does.

			 */

			ehci->reset_done[i] = jiffies + msecs_to_jiffies(25);

			set_bit(i, &ehci->resuming_ports);

			ehci_dbg (ehci, "port %d remote wakeup\n", i + 1);

			mod_timer(&hcd->rh_timer, ehci->reset_done[i]);

		}

drivers/usb/host/ehci-hub.c

+16 −15
Original line number Diff line number Diff line
@@ -223,17 +223,12 @@ static int ehci_bus_suspend (struct usb_hcd *hcd) 
	 * remote wakeup, we must fail the suspend.

	 */

	if (hcd->self.root_hub->do_remote_wakeup) {

		port = HCS_N_PORTS(ehci->hcs_params);

		while (port--) {

			if (ehci->reset_done[port] != 0) {

		if (ehci->resuming_ports) {

			spin_unlock_irq(&ehci->lock);

				ehci_dbg(ehci, "suspend failed because "

						"port %d is resuming\n",

						port + 1);

			ehci_dbg(ehci, "suspend failed because a port is resuming\n");

			return -EBUSY;

		}

	}

	}



	/* stop schedules, clean any completed work */

	if (ehci->rh_state == EHCI_RH_RUNNING)
@@ -554,16 +549,12 @@ static int 
ehci_hub_status_data (struct usb_hcd *hcd, char *buf)

{

	struct ehci_hcd	*ehci = hcd_to_ehci (hcd);

	u32		temp, status = 0;

	u32		temp, status;

	u32		mask;

	int		ports, i, retval = 1;

	unsigned long	flags;

	u32		ppcd = 0;



	/* if !USB_SUSPEND, root hub timers won't get shut down ... */

	if (ehci->rh_state != EHCI_RH_RUNNING)

		return 0;



	/* init status to no-changes */

	buf [0] = 0;

	ports = HCS_N_PORTS (ehci->hcs_params);
@@ -572,6 +563,11 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf) 
		retval++;

	}



	/* Inform the core about resumes-in-progress by returning

	 * a non-zero value even if there are no status changes.

	 */

	status = ehci->resuming_ports;



	/* Some boards (mostly VIA?) report bogus overcurrent indications,

	 * causing massive log spam unless we completely ignore them.  It

	 * may be relevant that VIA VT8235 controllers, where PORT_POWER is
@@ -846,6 +842,7 @@ static int ehci_hub_control ( 
				ehci_writel(ehci,

					temp & ~(PORT_RWC_BITS | PORT_RESUME),

					status_reg);

				clear_bit(wIndex, &ehci->resuming_ports);

				retval = handshake(ehci, status_reg,

					   PORT_RESUME, 0, 2000 /* 2msec */);

				if (retval != 0) {
@@ -864,6 +861,7 @@ static int ehci_hub_control ( 
					ehci->reset_done[wIndex])) {

			status |= USB_PORT_STAT_C_RESET << 16;

			ehci->reset_done [wIndex] = 0;

			clear_bit(wIndex, &ehci->resuming_ports);



			/* force reset to complete */

			ehci_writel(ehci, temp & ~(PORT_RWC_BITS | PORT_RESET),
@@ -884,8 +882,10 @@ static int ehci_hub_control ( 
					ehci_readl(ehci, status_reg));

		}



		if (!(temp & (PORT_RESUME|PORT_RESET)))

		if (!(temp & (PORT_RESUME|PORT_RESET))) {

			ehci->reset_done[wIndex] = 0;

			clear_bit(wIndex, &ehci->resuming_ports);

		}



		/* transfer dedicated ports to the companion hc */

		if ((temp & PORT_CONNECT) &&
@@ -920,6 +920,7 @@ static int ehci_hub_control ( 
			status |= USB_PORT_STAT_SUSPEND;

		} else if (test_bit(wIndex, &ehci->suspended_ports)) {

			clear_bit(wIndex, &ehci->suspended_ports);

			clear_bit(wIndex, &ehci->resuming_ports);

			ehci->reset_done[wIndex] = 0;

			if (temp & PORT_PE)

				set_bit(wIndex, &ehci->port_c_suspend);

drivers/usb/host/ehci-tegra.c

+2 −0
Original line number Diff line number Diff line
@@ -224,6 +224,7 @@ static int tegra_ehci_hub_control( 
		temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);

		/* start resume signalling */

		ehci_writel(ehci, temp | PORT_RESUME, status_reg);

		set_bit(wIndex-1, &ehci->resuming_ports);



		spin_unlock_irqrestore(&ehci->lock, flags);

		msleep(20);
@@ -236,6 +237,7 @@ static int tegra_ehci_hub_control( 
			pr_err("%s: timeout waiting for SUSPEND\n", __func__);



		ehci->reset_done[wIndex-1] = 0;

		clear_bit(wIndex-1, &ehci->resuming_ports);



		tegra->port_resuming = 1;

		goto done;

drivers/usb/host/ehci.h

+2 −0
Original line number Diff line number Diff line
@@ -117,6 +117,8 @@ struct ehci_hcd { /* one per controller */ 
			the change-suspend feature turned on */

	unsigned long		suspended_ports;	/* which ports are

			suspended */

	unsigned long		resuming_ports;		/* which ports have

			started to resume */



	/* per-HC memory pools (could be per-bus, but ...) */

	struct dma_pool		*qh_pool;	/* qh per active urb */

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