[PATCH 4.19 042/131] usb: dwc2: Postponed gadget registration to the udc class driver

[Sasha Levin]

From: Minas Harutyunyan <minas.harutyun...@synopsys.com>

commit 207324a321a866401b098cadf19e4a2dd6584622 upstream.

During dwc2 driver probe, after gadget registration to the udc class
driver, if exist any builtin function driver it immediately bound to
dwc2 and after init host side (dwc2_hcd_init()) stucked in host mode.
Patch postpone gadget registration after host side initialization done.

Fixes: 117777b2c3bb9 ("usb: dwc2: Move gadget probe function into platform 
code")
Reported-by: kbuild test robot <l...@intel.com>
Tested-by: Marek Vasut <ma...@denx.de>
Cc: stable <sta...@vger.kernel.org>
Signed-off-by: Minas Harutyunyan <hmi...@synopsys.com>
Link: 
https://lore.kernel.org/r/f21cb38fecc72a230b86155d94c7e60c9cb66f58.1591690938.git.hmi...@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/usb/dwc2/gadget.c   |  6 ------
 drivers/usb/dwc2/platform.c | 11 +++++++++++
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index d8424834902db..f18aa3f59e519 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -4759,12 +4759,6 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg)
                                          epnum, 0);
        }
 
-       ret = usb_add_gadget_udc(dev, &hsotg->gadget);
-       if (ret) {
-               dwc2_hsotg_ep_free_request(&hsotg->eps_out[0]->ep,
-                                          hsotg->ctrl_req);
-               return ret;
-       }
        dwc2_hsotg_dump(hsotg);
 
        return 0;
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 577642895b57d..c3383f30b37a4 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -492,6 +492,17 @@ static int dwc2_driver_probe(struct platform_device *dev)
        if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
                dwc2_lowlevel_hw_disable(hsotg);
 
+#if IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL) || \
+       IS_ENABLED(CONFIG_USB_DWC2_DUAL_ROLE)
+       /* Postponed adding a new gadget to the udc class driver list */
+       if (hsotg->gadget_enabled) {
+               retval = usb_add_gadget_udc(hsotg->dev, &hsotg->gadget);
+               if (retval) {
+                       dwc2_hsotg_remove(hsotg);
+                       goto error;
+               }
+       }
+#endif /* CONFIG_USB_DWC2_PERIPHERAL || CONFIG_USB_DWC2_DUAL_ROLE */
        return 0;
 
 error:
-- 
2.25.1