USB: EHCI: fix remote-wakeup support for ARC/TDI core

This patch (as1147) fixes the remote-wakeup support for EHCI
controllers using the ARC/TDI "embedded-TT" core.  These controllers
turn off the RESUME bit by themselves when a port resume is complete;
hence we need to keep separate track of which ports are suspended or
in the process of resuming.

The patch also makes a couple of small improvements in ehci_irq(),
replacing reads of the command register with the value already stored
in a local variable.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Thomas Reitmayr <treitmayr@devbase.at>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/ehci-hcd.c

@@ -706,7 +706,7 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
 		pcd_status = status;
 
 		/* resume root hub? */
-		if (!(ehci_readl(ehci, &ehci->regs->command) & CMD_RUN))
+		if (!(cmd & CMD_RUN))
 			usb_hcd_resume_root_hub(hcd);
 
 		while (i--) {
@@ -715,8 +715,11 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
 
 			if (pstatus & PORT_OWNER)
 				continue;
-			if (!(pstatus & PORT_RESUME)
-					|| ehci->reset_done [i] != 0)
+			if (!(test_bit(i, &ehci->suspended_ports) &&
+					((pstatus & PORT_RESUME) ||
+						!(pstatus & PORT_SUSPEND)) &&
+					(pstatus & PORT_PE) &&
+					ehci->reset_done[i] == 0))
 				continue;
 
 			/* start 20 msec resume signaling from this port,
@@ -731,9 +734,8 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
 
 	/* PCI errors [4.15.2.4] */
 	if (unlikely ((status & STS_FATAL) != 0)) {
-		dbg_cmd (ehci, "fatal", ehci_readl(ehci,
-						   &ehci->regs->command));
-		dbg_status (ehci, "fatal", status);
+		dbg_cmd(ehci, "fatal", cmd);
+		dbg_status(ehci, "fatal", status);
 		if (status & STS_HALT) {
 			ehci_err (ehci, "fatal error\n");
 dead:

drivers/usb/host/ehci-hub.c

@@ -236,10 +236,8 @@ static int ehci_bus_resume (struct usb_hcd *hcd)
 		temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
 		temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
 		if (test_bit(i, &ehci->bus_suspended) &&
-				(temp & PORT_SUSPEND)) {
-			ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
+				(temp & PORT_SUSPEND))
 			temp |= PORT_RESUME;
-		}
 		ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
 	}
 	i = HCS_N_PORTS (ehci->hcs_params);
@@ -482,10 +480,9 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
 		 * controller by the user.
 		 */
 
-		if ((temp & mask) != 0
-				|| ((temp & PORT_RESUME) != 0
-					&& time_after_eq(jiffies,
-						ehci->reset_done[i]))) {
+		if ((temp & mask) != 0 || test_bit(i, &ehci->port_c_suspend)
+				|| (ehci->reset_done[i] && time_after_eq(
+					jiffies, ehci->reset_done[i]))) {
 			if (i < 7)
 			    buf [0] |= 1 << (i + 1);
 			else
@@ -688,6 +685,7 @@ static int ehci_hub_control (
 			/* resume completed? */
 			else if (time_after_eq(jiffies,
 					ehci->reset_done[wIndex])) {
+				clear_bit(wIndex, &ehci->suspended_ports);
 				set_bit(wIndex, &ehci->port_c_suspend);
 				ehci->reset_done[wIndex] = 0;
 
@@ -734,6 +732,9 @@ static int ehci_hub_control (
 					ehci_readl(ehci, status_reg));
 		}
 
+		if (!(temp & (PORT_RESUME|PORT_RESET)))
+			ehci->reset_done[wIndex] = 0;
+
 		/* transfer dedicated ports to the companion hc */
 		if ((temp & PORT_CONNECT) &&
 				test_bit(wIndex, &ehci->companion_ports)) {
@@ -757,8 +758,17 @@ static int ehci_hub_control (
 		}
 		if (temp & PORT_PE)
 			status |= 1 << USB_PORT_FEAT_ENABLE;
-		if (temp & (PORT_SUSPEND|PORT_RESUME))
+
+		/* maybe the port was unsuspended without our knowledge */
+		if (temp & (PORT_SUSPEND|PORT_RESUME)) {
 			status |= 1 << USB_PORT_FEAT_SUSPEND;
+		} else if (test_bit(wIndex, &ehci->suspended_ports)) {
+			clear_bit(wIndex, &ehci->suspended_ports);
+			ehci->reset_done[wIndex] = 0;
+			if (temp & PORT_PE)
+				set_bit(wIndex, &ehci->port_c_suspend);
+		}
+
 		if (temp & PORT_OC)
 			status |= 1 << USB_PORT_FEAT_OVER_CURRENT;
 		if (temp & PORT_RESET)
@@ -803,6 +813,7 @@ static int ehci_hub_control (
 					|| (temp & PORT_RESET) != 0)
 				goto error;
 			ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
+			set_bit(wIndex, &ehci->suspended_ports);
 			break;
 		case USB_PORT_FEAT_POWER:
 			if (HCS_PPC (ehci->hcs_params))

drivers/usb/host/ehci.h

@@ -99,6 +99,8 @@ struct ehci_hcd {			/* one per controller */
 			owned by the companion during a bus suspend */
 	unsigned long		port_c_suspend;		/* which ports have
 			the change-suspend feature turned on */
+	unsigned long		suspended_ports;	/* which ports are
+			suspended */
 
 	/* per-HC memory pools (could be per-bus, but ...) */
 	struct dma_pool		*qh_pool;	/* qh per active urb */