From f0c89d5463d9d27679ca66b5bb86c161da15a3f7 Mon Sep 17 00:00:00 2001 From: Adrian Alonso Date: Thu, 6 Aug 2015 15:46:03 -0500 Subject: [PATCH] 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 --- drivers/usb/host/ehci-mx6.c | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-) diff --git a/drivers/usb/host/ehci-mx6.c b/drivers/usb/host/ehci-mx6.c index 54f868420d..2666351391 100644 --- 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); -- 2.39.5