Commit 383975d7 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

USB: EHCI, OHCI: handover changes 



This patch (as887) changes the way ehci-hcd and ohci-hcd handle a loss
of VBUS power during suspend.  In order for the USB-persist facility
to work correctly, it is necessary for low- and full-speed devices
attached to a high-speed port to be handed back to the companion
controller during resume processing.

This entails three changes: adding code to ehci-hcd to perform the
handover, removing code from ohci-hcd to turn off ports during
root-hub reinit, and adding code to ohci-hcd to turn on ports during
PCI controller resume.  (Other bus glue resume methods for platforms
supporting high-speed controllers would need a similar change, if any
existed.)

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 0458d5b4

drivers/usb/host/ehci-hcd.c

+2 −0
Original line number Diff line number Diff line
@@ -399,6 +399,8 @@ static void ehci_port_power (struct ehci_hcd *ehci, int is_on) 
				is_on ? SetPortFeature : ClearPortFeature,

				USB_PORT_FEAT_POWER,

				port--, NULL, 0);

	/* Flush those writes */

	ehci_readl(ehci, &ehci->regs->command);

	msleep(20);

}

drivers/usb/host/ehci-hub.c

+94 −5
Original line number Diff line number Diff line
@@ -28,6 +28,87 @@ 


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



#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 already owned by companion? */

			if (status & PORT_OWNER)

				clear_bit(port, &ehci->owned_ports);

			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)
@@ -60,14 +141,16 @@ static int ehci_bus_suspend (struct usb_hcd *hcd) 
	 * 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_PE) && !(t1 & PORT_OWNER) &&

				!(t1 & PORT_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);

		}
@@ -108,6 +191,7 @@ 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))
@@ -120,8 +204,9 @@ static int ehci_bus_resume (struct usb_hcd *hcd) 
	 * the last user of the controller, not reset/pm hardware keeping

	 * state we gave to it.

	 */

	temp = ehci_readl(ehci, &ehci->regs->intr_enable);

	ehci_dbg(ehci, "resume root hub%s\n", temp ? "" : " after power loss");

	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.
@@ -184,6 +269,9 @@ static int ehci_bus_resume (struct usb_hcd *hcd) 
	ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);



	spin_unlock_irq (&ehci->lock);



	if (!power_okay)

		ehci_handover_companion_ports(ehci);

	return 0;

}
@@ -448,7 +536,8 @@ static int ehci_hub_control ( 
) {

	struct ehci_hcd	*ehci = hcd_to_ehci (hcd);

	int		ports = HCS_N_PORTS (ehci->hcs_params);

	u32 __iomem	*status_reg = &ehci->regs->port_status[wIndex - 1];

	u32 __iomem	*status_reg = &ehci->regs->port_status[

				(wIndex & 0xff) - 1];

	u32		temp, status;

	unsigned long	flags;

	int		retval = 0;

drivers/usb/host/ehci-pci.c

+4 −3
Original line number Diff line number Diff line
@@ -312,13 +312,14 @@ static int ehci_pci_resume(struct usb_hcd *hcd) 
	ehci_work(ehci);

	spin_unlock_irq(&ehci->lock);



	/* here we "know" root ports should always stay powered */

	ehci_port_power(ehci, 1);



	ehci_writel(ehci, ehci->command, &ehci->regs->command);

	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);

	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */



	/* here we "know" root ports should always stay powered */

	ehci_port_power(ehci, 1);

	ehci_handover_companion_ports(ehci);



	hcd->state = HC_STATE_SUSPENDED;

	return 0;

}

drivers/usb/host/ehci.h

+3 −0
Original line number Diff line number Diff line
@@ -96,11 +96,14 @@ struct ehci_hcd { /* one per controller */ 


	/* per root hub port */

	unsigned long		reset_done [EHCI_MAX_ROOT_PORTS];



	/* bit vectors (one bit per port) */

	unsigned long		bus_suspended;		/* which ports were

			already suspended at the start of a bus suspend */

	unsigned long		companion_ports;	/* which ports are

			dedicated to the companion controller */

	unsigned long		owned_ports;		/* which ports are

			owned by the companion during a bus suspend */



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

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

drivers/usb/host/ohci-hcd.c

+2 −19
Original line number Diff line number Diff line
@@ -510,15 +510,7 @@ static int ohci_run (struct ohci_hcd *ohci) 
	// flush the writes

	(void) ohci_readl (ohci, &ohci->regs->control);

	msleep(temp);

	temp = roothub_a (ohci);

	if (!(temp & RH_A_NPS)) {

		/* power down each port */

		for (temp = 0; temp < ohci->num_ports; temp++)

			ohci_writel (ohci, RH_PS_LSDA,

				&ohci->regs->roothub.portstatus [temp]);

	}

	// flush those writes

	(void) ohci_readl (ohci, &ohci->regs->control);



	memset (ohci->hcca, 0, sizeof (struct ohci_hcca));



	/* 2msec timelimit here means no irqs/preempt */
@@ -826,17 +818,8 @@ static int ohci_restart (struct ohci_hcd *ohci) 
	if ((temp = ohci_run (ohci)) < 0) {

		ohci_err (ohci, "can't restart, %d\n", temp);

		return temp;

	} else {

		/* here we "know" root ports should always stay powered,

		 * and that if we try to turn them back on the root hub

		 * will respond to CSC processing.

		 */

		i = ohci->num_ports;

		while (i--)

			ohci_writel (ohci, RH_PS_PSS,

				&ohci->regs->roothub.portstatus [i]);

		ohci_dbg (ohci, "restart complete\n");

	}

	ohci_dbg(ohci, "restart complete\n");

	return 0;

}

#endif

CRA Git | Maintained and supported by SUSTech CRA and CCSE