imx: usb: ehci-mx6: wait_for_bit to check reg status

Add wait_for_bit to check reg bit status and replace unbounded
loops to check usb command status

Signed-off-by: Adrian Alonso <aalonso@freescale.com>

diff --git a/drivers/usb/host/ehci-mx6.c b/drivers/usb/host/ehci-mx6.c
index 54f868420d55af335df8341a74c9b9a42942fb9e..2666351391431e091a761fb92f7879777bde2625 100644 (file)
--- a/drivers/usb/host/ehci-mx6.c
+++ b/drivers/usb/host/ehci-mx6.c
@@ -117,12 +117,39 @@ static void usb_power_config(int index)
                     pll_480_ctrl_set);
 }
 
+static int wait_for_bit(u32 *reg, const u32 mask, bool set)
+{
+       u32 val;
+       const unsigned int timeout = 10000;
+       unsigned long start = get_timer(0);
+
+       while(1) {
+               val = readl(reg);
+               if (!set)
+                       val = ~val;
+
+               if ((val & mask) == mask)
+                       return 0;
+
+               if (get_timer(start) > timeout)
+                       break;
+
+               udelay(1);
+       }
+
+       debug("%s: Timeout (reg=%p mask=%08x wait_set=%i)\n",
+                       __func__, reg, mask, set);
+
+       return -ETIMEDOUT;
+}
+
 /* Return 0 : host node, <>0 : device mode */
 static int usb_phy_enable(int index, struct usb_ehci *ehci)
 {
        void __iomem *phy_reg;
        void __iomem *phy_ctrl;
        void __iomem *usb_cmd;
+       int ret;
 
        if (index >= ARRAY_SIZE(phy_bases))
                return 0;
@@ -133,12 +160,14 @@ static int usb_phy_enable(int index, struct usb_ehci *ehci)
 
        /* Stop then Reset */
        clrbits_le32(usb_cmd, UCMD_RUN_STOP);
-       while (readl(usb_cmd) & UCMD_RUN_STOP)
-               ;
+       ret = wait_for_bit(usb_cmd, UCMD_RUN_STOP, 0);
+       if (ret)
+               return ret;
 
        setbits_le32(usb_cmd, UCMD_RESET);
-       while (readl(usb_cmd) & UCMD_RESET)
-               ;
+       ret = wait_for_bit(usb_cmd, UCMD_RESET, 0);
+       if (ret)
+               return ret;
 
        /* Reset USBPHY module */
        setbits_le32(phy_ctrl, USBPHY_CTRL_SFTRST);