tegra: usb: host: Fix remote wakeup issues on UTMI

Add WAR to fix 2LS voilation during usb remote resume.

Bug 880538

Reviewed-on: http://git-master/r/75845

Change-Id: I552c9e657776f67c263ef750a7786c796dc785cb
Signed-off-by: Venkat Moganty <vmoganty@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Reviewed-on: http://git-master/r/76822
Reviewed-by: Automatic_Commit_Validation_User

3 files changed, 58 insertions, 8 deletions

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index ab94b512e0ea..1a534c70ea6e 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -906,6 +906,9 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
 			ehci->reset_done[i] = jiffies + msecs_to_jiffies(25);
 			ehci_dbg (ehci, "port %d remote wakeup\n", i + 1);
 			mod_timer(&hcd->rh_timer, ehci->reset_done[i]);
+#ifdef CONFIG_USB_EHCI_TEGRA
+			ehci->controller_remote_wakeup = true;
+#endif
 		}
 	}
 
diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index 917796c20d8a..1dbfc4aa1981 100644
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -167,11 +167,14 @@ static irqreturn_t tegra_ehci_irq (struct usb_hcd *hcd)
 	struct ehci_regs __iomem *hw = ehci->regs;
 	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);
 	u32 val;
+	irqreturn_t irq_status;
+	bool pmc_remote_wakeup = false;
 
 	if ((tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_UTMIP) &&
 		(tegra->ehci->has_hostpc)) {
 		/* check if there is any remote wake event */
 		if (tegra_usb_phy_is_remotewake_detected(tegra->phy)) {
+			pmc_remote_wakeup = true;
 			spin_lock (&ehci->lock);
 			usb_hcd_resume_root_hub(hcd);
 			spin_unlock (&ehci->lock);
@@ -196,7 +199,21 @@ static irqreturn_t tegra_ehci_irq (struct usb_hcd *hcd)
 		}
 		spin_unlock(&ehci->lock);
 	}
-	return ehci_irq(hcd);
+
+	irq_status = ehci_irq(hcd);
+
+	if (pmc_remote_wakeup) {
+		ehci->controller_remote_wakeup = false;
+	}
+
+	if (ehci->controller_remote_wakeup) {
+		ehci->controller_remote_wakeup = false;
+		/* disable interrupts */
+		ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+		tegra_usb_phy_preresume(tegra->phy, true);
+		tegra->port_resuming = 1;
+	}
+	return irq_status;
 }
 
 static int tegra_ehci_hub_control(
@@ -219,6 +236,7 @@ static int tegra_ehci_hub_control(
 	unsigned	selector;
 	struct		tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);
 	bool		hsic = false;
+	bool do_post_resume = false;
 
 	if (!tegra->host_resumed) {
 		if (buf)
@@ -244,13 +262,18 @@ static int tegra_ehci_hub_control(
 	} else if (typeReq == GetPortStatus) {
 		temp = ehci_readl(ehci, status_reg);
 		if (tegra->port_resuming && !(temp & PORT_SUSPEND) &&
-		    time_after_eq(jiffies, ehci->reset_done[wIndex-1])) {
-			/* Resume completed, re-enable disconnect detection */
-			tegra->port_resuming = 0;
+			time_after_eq(jiffies, ehci->reset_done[wIndex-1])) {
 			clear_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
 			ehci->reset_done[wIndex-1] = 0;
+			do_post_resume = true;
+		} else if (tegra->port_resuming && (temp & PORT_RESUME) &&
+			time_after_eq(jiffies, ehci->reset_done[wIndex-1]) ) {
+			do_post_resume = true;
+		}
+
+		if (do_post_resume) {
+			tegra->port_resuming = 0;
 			tegra_usb_phy_postresume(tegra->phy, false);
-#ifndef CONFIG_ARCH_TEGRA_2x_SOC
 			if (tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_UTMIP) {
 				ehci->command |= CMD_RUN;
 				/*
@@ -259,9 +282,11 @@ static int tegra_ehci_hub_control(
 				 */
 				ehci_writel(ehci, ehci->command,
 					&ehci->regs->command);
+				/* Now we can safely re-enable irqs */
+				ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);
 			}
-#endif
 		}
+
 	} else if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) {
 		temp = ehci_readl(ehci, status_reg);
 		if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) {
@@ -286,6 +311,13 @@ static int tegra_ehci_hub_control(
 
 		set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
 
+		if (tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_UTMIP) {
+			/* Disable RUN bit. */
+			ehci->command &= ~CMD_RUN;
+			ehci_writel(ehci, ehci->command,
+				&ehci->regs->command);
+		}
+
 		tegra_usb_phy_postsuspend(tegra->phy, false);
 
 		goto done;
@@ -318,6 +350,15 @@ static int tegra_ehci_hub_control(
 
 		tegra->port_resuming = 1;
 
+		if (tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_UTMIP) {
+			/* disable interrupts */
+			ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+			/* Disable RUN bit. */
+			ehci->command &= ~CMD_RUN;
+			ehci_writel(ehci, ehci->command,
+				&ehci->regs->command);
+		}
+
 		/* Disable disconnect detection during port resume */
 		tegra_usb_phy_preresume(tegra->phy, false);
 #ifndef CONFIG_ARCH_TEGRA_2x_SOC
@@ -509,6 +550,7 @@ static int tegra_usb_resume(struct usb_hcd *hcd, bool is_dpd)
 	unsigned long val;
 	bool hsic;
 	bool null_ulpi;
+	bool utmip_remote_wakeup = false;
 
 	null_ulpi = (tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_NULL_ULPI);
 	hsic = (tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_HSIC);
@@ -547,8 +589,7 @@ static int tegra_usb_resume(struct usb_hcd *hcd, bool is_dpd)
 
 	if ((tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_UTMIP) &&
 		(tegra->ehci->has_hostpc) && (tegra->phy->remote_wakeup)) {
-		ehci->command |= CMD_RUN;
-		ehci_writel(ehci, ehci->command, &ehci->regs->command);
+		utmip_remote_wakeup = true;
 	}
 
 	/* Check if the phy resume from LP0. When the phy resume from LP0
@@ -611,6 +652,10 @@ static int tegra_usb_resume(struct usb_hcd *hcd, bool is_dpd)
 	}
 
 	tegra_ehci_phy_restore_end(tegra->phy);
+	if (utmip_remote_wakeup) {
+		ehci->command |= CMD_RUN;
+		ehci_writel(ehci, ehci->command, &ehci->regs->command);
+	}
 	return 0;
 
 restart:
@@ -709,6 +754,7 @@ static int tegra_ehci_setup(struct usb_hcd *hcd)
 		return retval;
 
 	ehci->sbrn = 0x20;
+	ehci->controller_remote_wakeup = false;
 
 	if (tegra->phy->usb_phy_type == TEGRA_USB_PHY_TYPE_NULL_ULPI) {
 		tegra_ehci_pre_reset(tegra->phy, false);
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 7f0e828631ed..e897262c6a60 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -142,6 +142,7 @@ struct ehci_hcd {			/* one per controller */
 	unsigned		frame_index_bug:1; /* MosChip (AKA NetMos) */
 #ifdef CONFIG_USB_EHCI_TEGRA
 	unsigned		controller_resets_phy:1;
+	unsigned		controller_remote_wakeup:1;
 #endif
 
 	/* required for usb32 quirk */