[ 011/108] powerpc/usb: fix bug of kernel hang when initializing usb

[Greg KH]

3.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Shengzhou Liu <Shengzhou.Liu@xxxxxxxxxxxxx>

commit 28c56ea1431421dec51b7b229369e991481453df upstream.

If USB UTMI PHY is not enable, writing to portsc register will lead to
kernel hang during boot up.

Signed-off-by: Shengzhou Liu <Shengzhou.Liu@xxxxxxxxxxxxx>
Reported-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/host/ehci-fsl.c |    4 ++++
 drivers/usb/host/ehci-fsl.h |    1 +
 2 files changed, 5 insertions(+)

--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -216,6 +216,8 @@ static void ehci_fsl_setup_phy(struct eh
 			       unsigned int port_offset)
 {
 	u32 portsc;
+	struct usb_hcd *hcd = ehci_to_hcd(ehci);
+	void __iomem *non_ehci = hcd->regs;
 
 	portsc = ehci_readl(ehci, &ehci->regs->port_status[port_offset]);
 	portsc &= ~(PORT_PTS_MSK | PORT_PTS_PTW);
@@ -231,6 +233,8 @@ static void ehci_fsl_setup_phy(struct eh
 		portsc |= PORT_PTS_PTW;
 		/* fall through */
 	case FSL_USB2_PHY_UTMI:
+		/* enable UTMI PHY */
+		setbits32(non_ehci + FSL_SOC_USB_CTRL, CTRL_UTMI_PHY_EN);
 		portsc |= PORT_PTS_UTMI;
 		break;
 	case FSL_USB2_PHY_NONE:
--- a/drivers/usb/host/ehci-fsl.h
+++ b/drivers/usb/host/ehci-fsl.h
@@ -45,5 +45,6 @@
 #define FSL_SOC_USB_PRICTRL	0x40c	/* NOTE: big-endian */
 #define FSL_SOC_USB_SICTRL	0x410	/* NOTE: big-endian */
 #define FSL_SOC_USB_CTRL	0x500	/* NOTE: big-endian */
+#define CTRL_UTMI_PHY_EN	(1<<9)
 #define SNOOP_SIZE_2GB		0x1e
 #endif				/* _EHCI_FSL_H */


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/