Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed,  3 May 2023 00:31:44 +0000
Mime-Version: 1.0
Message-ID: <20230503003144.3782774-1-royluo@google.com>
Subject: [PATCH v1] usb: dwc3: Add error logs for unknown endpoint events
From:   Roy Luo <royluo@google.com>
To:     Thinh Nguyen <Thinh.Nguyen@synopsys.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        badhri@google.com, Roy Luo <royluo@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

In cases where the controller somehow fails to write to event buffer
memory (e.g. due to incorrect MMU config), the driver would receive
all-zero dwc3 events. However, the abnormal event is silently dropped
as a regular ep0out event.
Add error logs when an unknown endpoint event is received to highlight
the anamoly.

Signed-off-by: Roy Luo <royluo@google.com>
---
 drivers/usb/dwc3/ep0.c    | 2 ++
 drivers/usb/dwc3/gadget.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 953b752a5052..8c9560a9999e 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -1207,5 +1207,7 @@ void dwc3_ep0_interrupt(struct dwc3 *dwc,
 			dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
 		}
 		break;
+	default:
+		dev_err(dwc->dev, "unknown endpoint event %d\n", event->endpoint_event);
 	}
 }
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index c0ca4d12f95d..054f6f297e17 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3803,6 +3803,8 @@ static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
 		break;
 	case DWC3_DEPEVT_RXTXFIFOEVT:
 		break;
+	default:
+		dev_err(dwc->dev, "unknown endpoint event %d\n", event->endpoint_event);
 	}
 }
 

base-commit: c8c655c34e33544aec9d64b660872ab33c29b5f1
-- 
2.40.1.495.gc816e09b53d-goog