The phy needs some delay to output the stable status from low
power mode. And for OTGSC, the status inputs are debounced
using a 1 ms time constant, so, delay 2ms for controller to get
the stable status(like vbus and id) when the phy leaves low power.

Signed-off-by: Peter Chen <peter.c...@freescale.com>
---
 drivers/usb/chipidea/core.c |   17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index 69003d0..6cbfeb5 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -189,6 +189,17 @@ u8 hw_port_test_get(struct ci_hdrc *ci)
        return hw_read(ci, OP_PORTSC, PORTSC_PTC) >> __ffs(PORTSC_PTC);
 }
 
+static void hw_wait_phy_stable(void)
+{
+       /*
+        * The phy needs some delay to output the stable status from low
+        * power mode. And for OTGSC, the status inputs are debounced
+        * using a 1 ms time constant, so, delay 2ms for controller to get
+        * the stable status, like vbus and id when the phy leaves low power.
+        */
+       usleep_range(2000, 2500);
+}
+
 /* The PHY enters/leaves low power mode */
 static void ci_hdrc_enter_lpm(struct ci_hdrc *ci, bool enable)
 {
@@ -307,7 +318,9 @@ static int ci_usb_phy_init(struct ci_hdrc *ci)
        case USBPHY_INTERFACE_MODE_UTMIW:
        case USBPHY_INTERFACE_MODE_HSIC:
                ret = usb_phy_init(ci->transceiver);
-               if (ret)
+               if (!ret)
+                       hw_wait_phy_stable();
+               else
                        return ret;
                hw_phymode_configure(ci);
                break;
@@ -320,6 +333,8 @@ static int ci_usb_phy_init(struct ci_hdrc *ci)
                break;
        default:
                ret = usb_phy_init(ci->transceiver);
+               if (!ret)
+                       hw_wait_phy_stable();
        }
 
        return ret;
-- 
1.7.9.5

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