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Date:   Thu,  4 May 2023 00:01:29 +0000
Mime-Version: 1.0
Message-ID: <20230504000129.728316-1-royluo@google.com>
Subject: [PATCH v2] 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 anomaly.

Signed-off-by: Roy Luo <royluo@google.com>
---
 drivers/usb/dwc3/ep0.c    | 3 +++
 drivers/usb/dwc3/gadget.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 953b752a5052..b94243237293 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -1207,5 +1207,8 @@ 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);
+		break;
 	}
 }
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index c0ca4d12f95d..7163d5d0eea0 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3803,6 +3803,9 @@ 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);
+		break;
 	}
 }
 

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