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From: EJ Hsu <>
To: <>
Cc: <>, EJ Hsu <>
Subject: [PATCH v3] usb: gadget: fix wrong endpoint desc
Date: Tue, 3 Dec 2019 23:34:56 -0800
Message-ID: <> (raw)

Gadget driver should always use config_ep_by_speed() to initialize
usb_ep struct according to usb device's operating speed. Otherwise,
usb_ep struct may be wrong if usb devcie's operating speed is changed.

The key point in this patch is that we want to make sure the desc pointer
in usb_ep struct will be set to NULL when gadget is disconnected.
This will force it to call config_ep_by_speed() to correctly initialize
usb_ep struct based on the new operating speed when gadget is
re-connected later.

Signed-off-by: EJ Hsu <>
v2: fix the coding style
v3: fix the typo
 drivers/usb/gadget/function/f_ecm.c   | 6 +++++-
 drivers/usb/gadget/function/f_rndis.c | 1 +
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/f_ecm.c b/drivers/usb/gadget/function/f_ecm.c
index 6ce044008cf6..460d5d7c984f 100644
--- a/drivers/usb/gadget/function/f_ecm.c
+++ b/drivers/usb/gadget/function/f_ecm.c
@@ -621,8 +621,12 @@ static void ecm_disable(struct usb_function *f)
 	DBG(cdev, "ecm deactivated\n");
-	if (ecm->port.in_ep->enabled)
+	if (ecm->port.in_ep->enabled) {
+	} else {
+		ecm->port.in_ep->desc = NULL;
+		ecm->port.out_ep->desc = NULL;
+	}
 	ecm->notify->desc = NULL;
diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
index d48df36622b7..0d8e4a364ca6 100644
--- a/drivers/usb/gadget/function/f_rndis.c
+++ b/drivers/usb/gadget/function/f_rndis.c
@@ -618,6 +618,7 @@ static void rndis_disable(struct usb_function *f)
+	rndis->notify->desc = NULL;

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Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-12-04  7:34 EJ Hsu [this message]
2019-12-06  2:49 ` EJ Hsu

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