From d418b9a1df7e92e22646f72fd2f3b7515b4316ea Mon Sep 17 00:00:00 2001
From: Ajay Agarwal <ajaya@codeaurora.org>
Date: Fri, 30 Aug 2019 14:11:00 +0530
Subject: [PATCH] usb: dwc3-msm: Try core reset and reinit if PHY PLL lock
 fails

Add support for retrying core reset and re-initialization in host
mode if the PHY PLL lock failure is seen. Also, increase the lock
timeout to 50 msec.

Change-Id: I8c8db60dcd73b7cf05598538d0c519b1b1e2417f
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>
---
 drivers/usb/dwc3/dwc3-msm.c    | 22 +++++++++++++++++++++-
 drivers/usb/phy/phy-msm-qusb.c |  3 ++-
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-msm.c b/drivers/usb/dwc3/dwc3-msm.c
index 0650f0b69de7..7fec7b8e4dd9 100644
--- a/drivers/usb/dwc3/dwc3-msm.c
+++ b/drivers/usb/dwc3/dwc3-msm.c
@@ -276,6 +276,8 @@ struct dwc3_msm {
 	struct mutex suspend_resume_mutex;
 
 	enum usb_device_speed override_usb_speed;
+
+	bool core_init_failed;
 };
 
 #define USB_HSPHY_3P3_VOL_MIN		3050000 /* uV */
@@ -1953,12 +1955,20 @@ static void dwc3_msm_power_collapse_por(struct dwc3_msm *mdwc)
 		ret = dwc3_core_pre_init(dwc);
 		if (ret) {
 			dev_err(mdwc->dev, "dwc3_core_pre_init failed\n");
+			mdwc->core_init_failed = true;
 			return;
 		}
 		mdwc->init = true;
 	}
 
-	dwc3_core_init(dwc);
+	ret = dwc3_core_init(dwc);
+	if (ret) {
+		dev_err(mdwc->dev, "dwc3_core_init failed\n");
+		mdwc->core_init_failed = true;
+		return;
+	}
+
+	mdwc->core_init_failed = false;
 	/* Re-configure event buffers */
 	dwc3_event_buffers_setup(dwc);
 
@@ -3602,6 +3612,12 @@ static int dwc3_otg_start_host(struct dwc3_msm *mdwc, int on)
 		dev_dbg(mdwc->dev, "%s: turn on host\n", __func__);
 
 		pm_runtime_get_sync(mdwc->dev);
+		if (mdwc->core_init_failed) {
+			dev_err(mdwc->dev, "%s: Core init failed\n", __func__);
+			pm_runtime_put_sync_suspend(mdwc->dev);
+			return -EAGAIN;
+		}
+
 		mdwc->hs_phy->flags |= PHY_HOST_MODE;
 		if (dwc->maximum_speed == USB_SPEED_SUPER) {
 			mdwc->ss_phy->flags |= PHY_HOST_MODE;
@@ -4076,6 +4092,10 @@ static void dwc3_otg_sm_work(struct work_struct *w)
 				delay = VBUS_REG_CHECK_DELAY;
 				work = 1;
 				mdwc->vbus_retry_count++;
+			} else if (ret == -EAGAIN) {
+				mdwc->drd_state = DRD_STATE_HOST_IDLE;
+				dev_dbg(mdwc->dev, "Core init failed. Retrying...\n");
+				work = 1;
 			} else if (ret) {
 				dev_err(mdwc->dev, "unable to start host\n");
 				mdwc->drd_state = DRD_STATE_HOST_IDLE;
diff --git a/drivers/usb/phy/phy-msm-qusb.c b/drivers/usb/phy/phy-msm-qusb.c
index ae72ec6b3d19..1b09c028d098 100644
--- a/drivers/usb/phy/phy-msm-qusb.c
+++ b/drivers/usb/phy/phy-msm-qusb.c
@@ -862,7 +862,7 @@ static int qusb_phy_init(struct usb_phy *phy)
 		wmb();
 
 		/* Required to get PHY PLL lock successfully */
-		usleep_range(100, 110);
+		usleep_range(50000, 51000);
 	}
 
 	if (qphy->major_rev < 2) {
@@ -881,6 +881,7 @@ static int qusb_phy_init(struct usb_phy *phy)
 	if (pll_lock_fail) {
 		dev_err(phy->dev, "QUSB PHY PLL LOCK fails:%x\n", reg);
 		WARN_ON(1);
+		return -ETIMEDOUT;
 	}
 
 	return 0;