[PATCH 4.4 095/135] 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 842c1ae7a2911..e5ad717cba22f 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3656,12 +3656,6 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg, int irq)
                                                                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 39c1cbf0e75d9..5e554b1d5a8f9 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -452,6 +452,17 @@ 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