ehci-hub.c

usb driver for 2.6.17

/*
 * Copyright (C) 2001-2004 by David Brownell
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* this file is part of ehci-hcd.c */

/*-------------------------------------------------------------------------*/

/*
 * EHCI Root Hub ... the nonsharable stuff
 *
 * Registers don't need cpu_to_le32, that happens transparently
 */

/*-------------------------------------------------------------------------*/

#ifdef	CONFIG_PM

static int ehci_bus_suspend (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	int			port;

	if (time_before (jiffies, ehci->next_statechange))
		msleep(5);

	port = HCS_N_PORTS (ehci->hcs_params);
	spin_lock_irq (&ehci->lock);

	/* stop schedules, clean any completed work */
	if (HC_IS_RUNNING(hcd->state)) {
		ehci_quiesce (ehci);
		hcd->state = HC_STATE_QUIESCING;
	}
	ehci->command = readl (&ehci->regs->command);
	if (ehci->reclaim)
		ehci->reclaim_ready = 1;
	ehci_work(ehci, NULL);

	/* suspend any active/unsuspended ports, maybe allow wakeup */
	while (port--) {
		u32 __iomem	*reg = &ehci->regs->port_status [port];
		u32		t1 = readl (reg) & ~PORT_RWC_BITS;
		u32		t2 = t1;

		if ((t1 & PORT_PE) && !(t1 & PORT_OWNER))
			t2 |= PORT_SUSPEND;
		if (device_may_wakeup(&hcd->self.root_hub->dev))
			t2 |= PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E;
		else
			t2 &= ~(PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E);

		if (t1 != t2) {
			ehci_vdbg (ehci, "port %d, %08x -> %08x\n",
				port + 1, t1, t2);
			writel (t2, reg);
		}
	}

	/* turn off now-idle HC */
	del_timer_sync (&ehci->watchdog);
	ehci_halt (ehci);
	hcd->state = HC_STATE_SUSPENDED;

	ehci->next_statechange = jiffies + msecs_to_jiffies(10);
	spin_unlock_irq (&ehci->lock);
	return 0;
}


/* caller has locked the root hub, and should reset/reinit on error */
static int ehci_bus_resume (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	u32			temp;
	int			i;
	int			intr_enable;

	if (time_before (jiffies, ehci->next_statechange))
		msleep(5);
	spin_lock_irq (&ehci->lock);

	/* Ideally and we've got a real resume here, and no port's power
	 * was lost.  (For PCI, that means Vaux was maintained.)  But we
	 * could instead be restoring a swsusp snapshot -- so that BIOS was
	 * the last user of the controller, not reset/pm hardware keeping
	 * state we gave to it.
	 */

	/* re-init operational registers in case we lost power */
	if (readl (&ehci->regs->intr_enable) == 0) {
 		/* at least some APM implementations will try to deliver
		 * IRQs right away, so delay them until we're ready.
 		 */
 		intr_enable = 1;
		writel (0, &ehci->regs->segment);
		writel (ehci->periodic_dma, &ehci->regs->frame_list);
		writel ((u32)ehci->async->qh_dma, &ehci->regs->async_next);
	} else
		intr_enable = 0;
	ehci_dbg(ehci, "resume root hub%s\n",
			intr_enable ? " after power loss" : "");

	/* restore CMD_RUN, framelist size, and irq threshold */
	writel (ehci->command, &ehci->regs->command);

	/* take ports out of suspend */
	i = HCS_N_PORTS (ehci->hcs_params);
	while (i--) {
		temp = readl (&ehci->regs->port_status [i]);
		temp &= ~(PORT_RWC_BITS
			| PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E);
		if (temp & PORT_SUSPEND) {
			ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
			temp |= PORT_RESUME;
		}
		writel (temp, &ehci->regs->port_status [i]);
	}
	i = HCS_N_PORTS (ehci->hcs_params);
	mdelay (20);
	while (i--) {
		temp = readl (&ehci->regs->port_status [i]);
		if ((temp & PORT_SUSPEND) == 0)
			continue;
		temp &= ~(PORT_RWC_BITS | PORT_RESUME);
		writel (temp, &ehci->regs->port_status [i]);
		ehci_vdbg (ehci, "resumed port %d\n", i + 1);
	}
	(void) readl (&ehci->regs->command);

	/* maybe re-activate the schedule(s) */
	temp = 0;
	if (ehci->async->qh_next.qh)
		temp |= CMD_ASE;
	if (ehci->periodic_sched)
		temp |= CMD_PSE;
	if (temp) {
		ehci->command |= temp;
		writel (ehci->command, &ehci->regs->command);
	}

	ehci->next_statechange = jiffies + msecs_to_jiffies(5);
	hcd->state = HC_STATE_RUNNING;

	/* Now we can safely re-enable irqs */
	if (intr_enable)
		writel (INTR_MASK, &ehci->regs->intr_enable);

	spin_unlock_irq (&ehci->lock);
	return 0;
}

#else

#define ehci_bus_suspend	NULL
#define ehci_bus_resume		NULL

#endif	/* CONFIG_PM */

/*-------------------------------------------------------------------------*/

static int check_reset_complete (
	struct ehci_hcd	*ehci,
	int		index,
	int		port_status
) {
	if (!(port_status & PORT_CONNECT)) {
		ehci->reset_done [index] = 0;
		return port_status;
	}

	/* if reset finished and it's still not enabled -- handoff */
	if (!(port_status & PORT_PE)) {

		/* with integrated TT, there's nobody to hand it to! */
		if (ehci_is_TDI(ehci)) {
			ehci_dbg (ehci,
				"Failed to enable port %d on root hub TT\n",
				index+1);
			return port_status;
		}

		ehci_dbg (ehci, "port %d full speed --> companion\n",
			index + 1);

		// what happens if HCS_N_CC(params) == 0 ?
		port_status |= PORT_OWNER;
		port_status &= ~PORT_RWC_BITS;
		writel (port_status, &ehci->regs->port_status [index]);

	} else
		ehci_dbg (ehci, "port %d high speed\n", index + 1);

	return port_status;
}

/*-------------------------------------------------------------------------*/


/* build "status change" packet (one or two bytes) from HC registers */

static int
ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
{
	struct ehci_hcd	*ehci = hcd_to_ehci (hcd);
	u32		temp, status = 0;
	int		ports, i, retval = 1;
	unsigned long	flags;

	/* if !USB_SUSPEND, root hub timers won't get shut down ... */
	if (!HC_IS_RUNNING(hcd->state))
		return 0;

	/* init status to no-changes */
	buf [0] = 0;
	ports = HCS_N_PORTS (ehci->hcs_params);
	if (ports > 7) {
		buf [1] = 0;
		retval++;
	}
	
	/* no hub change reports (bit 0) for now (power, ...) */

	/* port N changes (bit N)? */
	spin_lock_irqsave (&ehci->lock, flags);
	for (i = 0; i < ports; i++) {
		temp = readl (&ehci->regs->port_status [i]);
		if (temp & PORT_OWNER) {
			/* don't report this in GetPortStatus */
			if (temp & PORT_CSC) {
				temp &= ~PORT_RWC_BITS;
				temp |= PORT_CSC;
				writel (temp, &ehci->regs->port_status [i]);
			}
			continue;
		}
		if (!(temp & PORT_CONNECT))
			ehci->reset_done [i] = 0;
		if ((temp & (PORT_CSC | PORT_PEC | PORT_OCC)) != 0
				// PORT_STAT_C_SUSPEND?
				|| ((temp & PORT_RESUME) != 0
					&& time_after (jiffies,
						ehci->reset_done [i]))) {
			if (i < 7)
			    buf [0] |= 1 << (i + 1);
			else
			    buf [1] |= 1 << (i - 7);
			status = STS_PCD;
		}
	}
	/* FIXME autosuspend idle root hubs */
	spin_unlock_irqrestore (&ehci->lock, flags);
	return status ? retval : 0;
}

/*-------------------------------------------------------------------------*/

static void
ehci_hub_descriptor (
	struct ehci_hcd			*ehci,
	struct usb_hub_descriptor	*desc
) {
	int		ports = HCS_N_PORTS (ehci->hcs_params);
	u16		temp;

	desc->bDescriptorType = 0x29;
	desc->bPwrOn2PwrGood = 10;	/* ehci 1.0, 2.3.9 says 20ms max */
	desc->bHubContrCurrent = 0;

	desc->bNbrPorts = ports;
	temp = 1 + (ports / 8);
	desc->bDescLength = 7 + 2 * temp;

	/* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */