usb: phy: mxs: Add sync time after controller clear phcd
authorPeter Chen <peter.chen@freescale.com>
Mon, 24 Feb 2014 02:21:04 +0000 (10:21 +0800)
committerFelipe Balbi <balbi@ti.com>
Wed, 5 Mar 2014 20:40:09 +0000 (14:40 -0600)
After clear portsc.phcd, PHY needs 200us stable time for switch
32K clock to AHB clock.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
drivers/usb/phy/phy-mxs-usb.c

index 31ef59f88901b6918ab5dd202fb0cdb617240121..c42bdf0c4a1f7322eed6ba4f7ce6b058f7c16fd9 100644 (file)
@@ -151,6 +151,15 @@ static inline bool is_imx6sl_phy(struct mxs_phy *mxs_phy)
        return mxs_phy->data == &imx6sl_phy_data;
 }
 
+/*
+ * PHY needs some 32K cycles to switch from 32K clock to
+ * bus (such as AHB/AXI, etc) clock.
+ */
+static void mxs_phy_clock_switch_delay(void)
+{
+       usleep_range(300, 400);
+}
+
 static int mxs_phy_hw_init(struct mxs_phy *mxs_phy)
 {
        int ret;
@@ -261,6 +270,7 @@ static int mxs_phy_init(struct usb_phy *phy)
        int ret;
        struct mxs_phy *mxs_phy = to_mxs_phy(phy);
 
+       mxs_phy_clock_switch_delay();
        ret = clk_prepare_enable(mxs_phy->clk);
        if (ret)
                return ret;
@@ -289,6 +299,7 @@ static int mxs_phy_suspend(struct usb_phy *x, int suspend)
                       x->io_priv + HW_USBPHY_CTRL_SET);
                clk_disable_unprepare(mxs_phy->clk);
        } else {
+               mxs_phy_clock_switch_delay();
                ret = clk_prepare_enable(mxs_phy->clk);
                if (ret)
                        return ret;