ehci-hub.c

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/*
 * 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_USB_PERSIST

static int ehci_hub_control(
	struct usb_hcd	*hcd,
	u16		typeReq,
	u16		wValue,
	u16		wIndex,
	char		*buf,
	u16		wLength
);

/* After a power loss, ports that were owned by the companion must be
 * reset so that the companion can still own them.
 */
static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
{
	u32 __iomem	*reg;
	u32		status;
	int		port;
	__le32		buf;
	struct usb_hcd	*hcd = ehci_to_hcd(ehci);

	if (!ehci->owned_ports)
		return;

	/* Give the connections some time to appear */
	msleep(20);

	port = HCS_N_PORTS(ehci->hcs_params);
	while (port--) {
		if (test_bit(port, &ehci->owned_ports)) {
			reg = &ehci->regs->port_status[port];
			status = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;

			/* Port already owned by companion? */
			if (status & PORT_OWNER)
				clear_bit(port, &ehci->owned_ports);
			else if (test_bit(port, &ehci->companion_ports))
				ehci_writel(ehci, status & ~PORT_PE, reg);
			else
				ehci_hub_control(hcd, SetPortFeature,
						USB_PORT_FEAT_RESET, port + 1,
						NULL, 0);
		}
	}

	if (!ehci->owned_ports)
		return;
	msleep(90);		/* Wait for resets to complete */

	port = HCS_N_PORTS(ehci->hcs_params);
	while (port--) {
		if (test_bit(port, &ehci->owned_ports)) {
			ehci_hub_control(hcd, GetPortStatus,
					0, port + 1,
					(char *) &buf, sizeof(buf));

			/* The companion should now own the port,
			 * but if something went wrong the port must not
			 * remain enabled.
			 */
			reg = &ehci->regs->port_status[port];
			status = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
			if (status & PORT_OWNER)
				ehci_writel(ehci, status | PORT_CSC, reg);
			else {
				ehci_dbg(ehci, "failed handover port %d: %x\n",
						port + 1, status);
				ehci_writel(ehci, status & ~PORT_PE, reg);
			}
		}
	}

	ehci->owned_ports = 0;
}

#else	/* CONFIG_USB_PERSIST */

static inline void ehci_handover_companion_ports(struct ehci_hcd *ehci)
{ }

#endif

#ifdef	CONFIG_PM

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

	ehci_dbg(ehci, "suspend root hub\n");

	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 = ehci_readl(ehci, &ehci->regs->command);
	if (ehci->reclaim)
		ehci->reclaim_ready = 1;
	ehci_work(ehci);

	/* Unlike other USB host controller types, EHCI doesn't have
	 * any notion of "global" or bus-wide suspend.  The driver has
	 * to manually suspend all the active unsuspended ports, and
	 * then manually resume them in the bus_resume() routine.
	 */
	ehci->bus_suspended = 0;
	ehci->owned_ports = 0;
	while (port--) {
		u32 __iomem	*reg = &ehci->regs->port_status [port];
		u32		t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
		u32		t2 = t1;

		/* keep track of which ports we suspend */
		if (t1 & PORT_OWNER)
			set_bit(port, &ehci->owned_ports);
		else if ((t1 & PORT_PE) && !(t1 & PORT_SUSPEND)) {
			t2 |= PORT_SUSPEND;
			set_bit(port, &ehci->bus_suspended);
		}

		/* enable remote wakeup on all ports */
		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);
			ehci_writel(ehci, t2, reg);
		}
	}

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

	/* allow remote wakeup */
	mask = INTR_MASK;
	if (!device_may_wakeup(&hcd->self.root_hub->dev))
		mask &= ~STS_PCD;
	ehci_writel(ehci, mask, &ehci->regs->intr_enable);
	ehci_readl(ehci, &ehci->regs->intr_enable);

	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;
	u32			power_okay;
	int			i;

	if (time_before (jiffies, ehci->next_statechange))
		msleep(5);
	spin_lock_irq (&ehci->lock);
	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
		spin_unlock_irq(&ehci->lock);
		return -ESHUTDOWN;
	}

	/* 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.
	 */
	power_okay = ehci_readl(ehci, &ehci->regs->intr_enable);
	ehci_dbg(ehci, "resume root hub%s\n",
			power_okay ? "" : " after power loss");

	/* at least some APM implementations will try to deliver
	 * IRQs right away, so delay them until we're ready.
	 */
	ehci_writel(ehci, 0, &ehci->regs->intr_enable);

	/* re-init operational registers */
	ehci_writel(ehci, 0, &ehci->regs->segment);
	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
	ehci_writel(ehci, (u32) ehci->async->qh_dma, &ehci->regs->async_next);

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

	/* Some controller/firmware combinations need a delay during which
	 * they set up the port statuses.  See Bugzilla #8190. */
	mdelay(8);

	/* manually resume the ports we suspended during bus_suspend() */
	i = HCS_N_PORTS (ehci->hcs_params);
	while (i--) {
		temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
		temp &= ~(PORT_RWC_BITS
			| PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E);
		if (test_bit(i, &ehci->bus_suspended) &&
				(temp & PORT_SUSPEND)) {
			ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
			temp |= PORT_RESUME;
		}
		ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
	}
	i = HCS_N_PORTS (ehci->hcs_params);
	mdelay (20);
	while (i--) {
		temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
		if (test_bit(i, &ehci->bus_suspended) &&
				(temp & PORT_SUSPEND)) {
			temp &= ~(PORT_RWC_BITS | PORT_RESUME);
			ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
			ehci_vdbg (ehci, "resumed port %d\n", i + 1);
		}
	}
	(void) ehci_readl(ehci, &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;
		ehci_writel(ehci, 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 */
	ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);

	spin_unlock_irq (&ehci->lock);

	if (!power_okay)
		ehci_handover_companion_ports(ehci);
	return 0;
}

#else

#define ehci_bus_suspend	NULL
#define ehci_bus_resume		NULL

#endif	/* CONFIG_PM */

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

/* Display the ports dedicated to the companion controller */
static ssize_t show_companion(struct class_device *class_dev, char *buf)
{
	struct ehci_hcd		*ehci;
	int			nports, index, n;
	int			count = PAGE_SIZE;
	char			*ptr = buf;

	ehci = hcd_to_ehci(bus_to_hcd(class_get_devdata(class_dev)));
	nports = HCS_N_PORTS(ehci->hcs_params);

	for (index = 0; index < nports; ++index) {
		if (test_bit(index, &ehci->companion_ports)) {
			n = scnprintf(ptr, count, "%d\n", index + 1);
			ptr += n;
			count -= n;
		}
	}
	return ptr - buf;
}

/*
 * Dedicate or undedicate a port to the companion controller.
 * Syntax is "[-]portnum", where a leading '-' sign means
 * return control of the port to the EHCI controller.
 */
static ssize_t store_companion(struct class_device *class_dev,
		const char *buf, size_t count)
{
	struct ehci_hcd		*ehci;
	int			portnum, new_owner, try;
	u32 __iomem		*status_reg;
	u32			port_status;

	ehci = hcd_to_ehci(bus_to_hcd(class_get_devdata(class_dev)));
	new_owner = PORT_OWNER;		/* Owned by companion */
	if (sscanf(buf, "%d", &portnum) != 1)
		return -EINVAL;
	if (portnum < 0) {
		portnum = - portnum;
		new_owner = 0;		/* Owned by EHCI */
	}
	if (portnum <= 0 || portnum > HCS_N_PORTS(ehci->hcs_params))
		return -ENOENT;
	status_reg = &ehci->regs->port_status[--portnum];
	if (new_owner)
		set_bit(portnum, &ehci->companion_ports);
	else
		clear_bit(portnum, &ehci->companion_ports);

	/*
	 * The controller won't set the OWNER bit if the port is
	 * enabled, so this loop will sometimes require at least two
	 * iterations: one to disable the port and one to set OWNER.
	 */

	for (try = 4; try > 0; --try) {
		spin_lock_irq(&ehci->lock);
		port_status = ehci_readl(ehci, status_reg);
		if ((port_status & PORT_OWNER) == new_owner
				|| (port_status & (PORT_OWNER | PORT_CONNECT))
					== 0)
			try = 0;
		else {
			port_status ^= PORT_OWNER;
			port_status &= ~(PORT_PE | PORT_RWC_BITS);
			ehci_writel(ehci, port_status, status_reg);
		}
		spin_unlock_irq(&ehci->lock);
		if (try > 1)
			msleep(5);
	}
	return count;
}
static CLASS_DEVICE_ATTR(companion, 0644, show_companion, store_companion);

static inline void create_companion_file(struct ehci_hcd *ehci)
{
	int	i;

	/* with integrated TT there is no companion! */
	if (!ehci_is_TDI(ehci))
		i = class_device_create_file(ehci_to_hcd(ehci)->self.class_dev,
				&class_device_attr_companion);
}

static inline void remove_companion_file(struct ehci_hcd *ehci)
{
	/* with integrated TT there is no companion! */
	if (!ehci_is_TDI(ehci))
		class_device_remove_file(ehci_to_hcd(ehci)->self.class_dev,
				&class_device_attr_companion);
}


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

static int check_reset_complete (
	struct ehci_hcd	*ehci,
	int		index,
	u32 __iomem	*status_reg,
	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;
		ehci_writel(ehci, port_status, status_reg);

	} 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);