From e6f2f6d63e3b0c4e75011f09ecbdbe093d5f2eb1 Mon Sep 17 00:00:00 2001
From: William Wu <william.wu@rock-chips.com>
Date: Wed, 7 Mar 2018 18:13:37 +0800
Subject: [PATCH] usb: dwc2: power on/off phy for otg mode

The commit dc71e5194420 ("usb: dwc2: make otg manage lowlevel
hw on its own") aimed to control the clk and phy power for
otg mode, but it also introduced lost of new problems, so we
revert it.

This patch only controls phy power for otg mode, it can fix
the dwc2 udc start fail issue with the following error log:

dwc2_hsotg_init_fifo: timeout flushing fifos (GRSTCTL=80000430)
dwc2_core_reset() HANG! Soft Reset GRSTCTL=80000001
bound driver configfs-gadget
dwc2_core_reset() HANG! Soft Reset GRSTCTL=80000001

Change-Id: Id6996aecab7f0aaaf12530b7a377144e23ef1667
Signed-off-by: William Wu <william.wu@rock-chips.com>
---
 drivers/usb/dwc2/gadget.c   | 32 ++++++++++++++++++++++++++++++++
 drivers/usb/dwc2/platform.c | 13 +++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 1330ab8e29c2..0c4fa75a1f72 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -26,6 +26,7 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/of_platform.h>
+#include <linux/platform_data/s3c-hsotg.h>
 
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
@@ -3465,6 +3466,24 @@ static int dwc2_hsotg_udc_start(struct usb_gadget *gadget,
 			goto err;
 	}
 
+	if (hsotg->dr_mode == USB_DR_MODE_OTG) {
+		struct platform_device *pdev = to_platform_device(hsotg->dev);
+
+		if (hsotg->uphy) {
+			ret = usb_phy_init(hsotg->uphy);
+		} else if (hsotg->plat && hsotg->plat->phy_init) {
+			ret = hsotg->plat->phy_init(pdev,
+						    hsotg->plat->phy_type);
+		} else {
+			ret = phy_power_on(hsotg->phy);
+			if (ret == 0)
+				ret = phy_init(hsotg->phy);
+		}
+
+		if (ret)
+			goto err;
+	}
+
 	if (!IS_ERR_OR_NULL(hsotg->uphy))
 		otg_set_peripheral(hsotg->uphy->otg, &hsotg->gadget);
 
@@ -3524,6 +3543,19 @@ static int dwc2_hsotg_udc_stop(struct usb_gadget *gadget)
 	if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
 		dwc2_lowlevel_hw_disable(hsotg);
 
+	if (hsotg->dr_mode == USB_DR_MODE_OTG) {
+		struct platform_device *pdev = to_platform_device(hsotg->dev);
+
+		if (hsotg->uphy) {
+			usb_phy_shutdown(hsotg->uphy);
+		} else if (hsotg->plat && hsotg->plat->phy_exit) {
+			hsotg->plat->phy_exit(pdev, hsotg->plat->phy_type);
+		} else {
+			phy_exit(hsotg->phy);
+			phy_power_off(hsotg->phy);
+		}
+	}
+
 	return 0;
 }
 
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index cada275a5f5f..47a1b6dd3a18 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -654,6 +654,19 @@ static int dwc2_driver_probe(struct platform_device *dev)
 	if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
 		dwc2_lowlevel_hw_disable(hsotg);
 
+	if (hsotg->dr_mode == USB_DR_MODE_OTG) {
+		struct platform_device *pdev = to_platform_device(hsotg->dev);
+
+		if (hsotg->uphy) {
+			usb_phy_shutdown(hsotg->uphy);
+		} else if (hsotg->plat && hsotg->plat->phy_exit) {
+			hsotg->plat->phy_exit(pdev, hsotg->plat->phy_type);
+		} else {
+			phy_exit(hsotg->phy);
+			phy_power_off(hsotg->phy);
+		}
+	}
+
 	return 0;
 
 error: