powerpc/usb: fix bug of kernel hang when initializing usb

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@freescale.com>
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index b556a72..da487fd 100644 (file)
--- 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 ehci_hcd *ehci,
                               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 ehci_hcd *ehci,
                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:

diff --git a/drivers/usb/host/ehci-fsl.h b/drivers/usb/host/ehci-fsl.h
index 4918062..bea5013 100644 (file)
--- 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 */