4 files changed, 111 insertions, 2 deletions

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 38650707dfe0..97a53a48a3d8 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -434,8 +434,15 @@ static int check_reset_complete (
 		port_status &= ~PORT_RWC_BITS;
 		ehci_writel(ehci, port_status, status_reg);
 
-	} else
+		/* ensure 440EPX ohci controller state is operational */
+		if (ehci->has_amcc_usb23)
+			set_ohci_hcfs(ehci, 1);
+	} else {
 		ehci_dbg (ehci, "port %d high speed\n", index + 1);
+		/* ensure 440EPx ohci controller state is suspended */
+		if (ehci->has_amcc_usb23)
+			set_ohci_hcfs(ehci, 0);
+	}
 
 	return port_status;
 }
diff --git a/drivers/usb/host/ehci-ppc-of.c b/drivers/usb/host/ehci-ppc-of.c
index b018deed2e8f..ef732b704f53 100644
--- a/drivers/usb/host/ehci-ppc-of.c
+++ b/drivers/usb/host/ehci-ppc-of.c
@@ -107,11 +107,13 @@ ehci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
 {
 	struct device_node *dn = op->node;
 	struct usb_hcd *hcd;
-	struct ehci_hcd	*ehci;
+	struct ehci_hcd	*ehci = NULL;
 	struct resource res;
 	int irq;
 	int rv;
 
+	struct device_node *np;
+
 	if (usb_disabled())
 		return -ENODEV;
 
@@ -149,6 +151,20 @@ ehci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
 	}
 
 	ehci = hcd_to_ehci(hcd);
+	np = of_find_compatible_node(NULL, NULL, "ibm,usb-ohci-440epx");
+	if (np != NULL) {
+		/* claim we really affected by usb23 erratum */
+		if (!of_address_to_resource(np, 0, &res))
+			ehci->ohci_hcctrl_reg = ioremap(res.start +
+					OHCI_HCCTRL_OFFSET, OHCI_HCCTRL_LEN);
+		else
+			pr_debug(__FILE__ ": no ohci offset in fdt\n");
+		if (!ehci->ohci_hcctrl_reg) {
+			pr_debug(__FILE__ ": ioremap for ohci hcctrl failed\n");
+		} else {
+			ehci->has_amcc_usb23 = 1;
+		}
+	}
 
 	if (of_get_property(dn, "big-endian", NULL)) {
 		ehci->big_endian_mmio = 1;
@@ -181,6 +197,9 @@ err_ioremap:
 	irq_dispose_mapping(irq);
 err_irq:
 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
+
+	if (ehci->has_amcc_usb23)
+		iounmap(ehci->ohci_hcctrl_reg);
 err_rmr:
 	usb_put_hcd(hcd);
 
@@ -191,6 +210,11 @@ err_rmr:
 static int ehci_hcd_ppc_of_remove(struct of_device *op)
 {
 	struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
+	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+
+	struct device_node *np;
+	struct resource res;
+
 	dev_set_drvdata(&op->dev, NULL);
 
 	dev_dbg(&op->dev, "stopping PPC-OF USB Controller\n");
@@ -201,6 +225,25 @@ static int ehci_hcd_ppc_of_remove(struct of_device *op)
 	irq_dispose_mapping(hcd->irq);
 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 
+	/* use request_mem_region to test if the ohci driver is loaded.  if so
+	 * ensure the ohci core is operational.
+	 */
+	if (ehci->has_amcc_usb23) {
+		np = of_find_compatible_node(NULL, NULL, "ibm,usb-ohci-440epx");
+		if (np != NULL) {
+			if (!of_address_to_resource(np, 0, &res))
+				if (!request_mem_region(res.start,
+							    0x4, hcd_name))
+					set_ohci_hcfs(ehci, 1);
+				else
+					release_mem_region(res.start, 0x4);
+			else
+				pr_debug(__FILE__ ": no ohci offset in fdt\n");
+			of_node_put(np);
+		}
+
+		iounmap(ehci->ohci_hcctrl_reg);
+	}
 	usb_put_hcd(hcd);
 
 	return 0;
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index c7d4b5a06bdb..fb7054ccf4fc 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -120,6 +120,16 @@ struct ehci_hcd {			/* one per controller */
 	unsigned		has_fsl_port_bug:1; /* FreeScale */
 	unsigned		big_endian_mmio:1;
 	unsigned		big_endian_desc:1;
+	unsigned		has_amcc_usb23:1;
+
+	/* required for usb32 quirk */
+	#define OHCI_CTRL_HCFS          (3 << 6)
+	#define OHCI_USB_OPER           (2 << 6)
+	#define OHCI_USB_SUSPEND        (3 << 6)
+
+	#define OHCI_HCCTRL_OFFSET      0x4
+	#define OHCI_HCCTRL_LEN         0x4
+	__hc32			*ohci_hcctrl_reg;
 
 	u8			sbrn;		/* packed release number */
 
@@ -636,6 +646,30 @@ static inline void ehci_writel(const struct ehci_hcd *ehci,
 #endif
 }
 
+/*
+ * On certain ppc-44x SoC there is a HW issue, that could only worked around with
+ * explicit suspend/operate of OHCI. This function hereby makes sense only on that arch.
+ * Other common bits are dependant on has_amcc_usb23 quirk flag.
+ */
+#ifdef CONFIG_44x
+static inline void set_ohci_hcfs(struct ehci_hcd *ehci, int operational)
+{
+	u32 hc_control;
+
+	hc_control = (readl_be(ehci->ohci_hcctrl_reg) & ~OHCI_CTRL_HCFS);
+	if (operational)
+		hc_control |= OHCI_USB_OPER;
+	else
+		hc_control |= OHCI_USB_SUSPEND;
+
+	writel_be(hc_control, ehci->ohci_hcctrl_reg);
+	(void) readl_be(ehci->ohci_hcctrl_reg);
+}
+#else
+static inline void set_ohci_hcfs(struct ehci_hcd *ehci, int operational)
+{ }
+#endif
+
 /*-------------------------------------------------------------------------*/
 
 /*
diff --git a/drivers/usb/host/ohci-ppc-of.c b/drivers/usb/host/ohci-ppc-of.c
index 7ac53264ead3..68a301710297 100644
--- a/drivers/usb/host/ohci-ppc-of.c
+++ b/drivers/usb/host/ohci-ppc-of.c
@@ -91,6 +91,7 @@ ohci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
 
 	int rv;
 	int is_bigendian;
+	struct device_node *np;
 
 	if (usb_disabled())
 		return -ENODEV;
@@ -147,6 +148,30 @@ ohci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
 	if (rv == 0)
 		return 0;
 
+	/* by now, 440epx is known to show usb_23 erratum */
+	np = of_find_compatible_node(NULL, NULL, "ibm,usb-ehci-440epx");
+
+	/* Work around - At this point ohci_run has executed, the
+	* controller is running, everything, the root ports, etc., is
+	* set up.  If the ehci driver is loaded, put the ohci core in
+	* the suspended state.  The ehci driver will bring it out of
+	* suspended state when / if a non-high speed USB device is
+	* attached to the USB Host port.  If the ehci driver is not
+	* loaded, do nothing. request_mem_region is used to test if
+	* the ehci driver is loaded.
+	*/
+	if (np !=  NULL) {
+		if (!of_address_to_resource(np, 0, &res)) {
+			if (!request_mem_region(res.start, 0x4, hcd_name)) {
+				writel_be((readl_be(&ohci->regs->control) |
+					OHCI_USB_SUSPEND), &ohci->regs->control);
+					(void) readl_be(&ohci->regs->control);
+			} else
+				release_mem_region(res.start, 0x4);
+		} else
+		    pr_debug(__FILE__ ": cannot get ehci offset from fdt\n");
+	}
+
 	iounmap(hcd->regs);
 err_ioremap:
 	irq_dispose_mapping(irq);