From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B508F21773D; Tue, 8 Jul 2025 16:36:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751992575; cv=none; b=G8T38ytBAdK054B8/4z2oNZHTvhfBsKJx7KTeTyksNmozXPSOEEURUEoZ0oCsHSYf9FM27owWYy7RYrp7q0sSnGYW0bLEDqaYzvoxTJelBs5o+VGU2QtyMHOd2ZX/fIO/yDibYNhFreSbzIKpVwEqMEnt/pYm2dNvIyBcd4no4Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751992575; c=relaxed/simple; bh=MvuQDNH0mc5mOoyR6j6P0tZwFdfbN2cVyha1il82h70=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cP/wvX6ruCudRTF+aCLS1/c/YRs7KVzbRLYo1wmtIs0CXw6GYbV5tZbRzK1cpIFksh5IDAobNQsmg72lH2cTGnSNhGwKAkBAoPDE6Uqj6Q8Jet3NOGCnRmbHMQXcXp1r4cpRQi79HE4QfLnY1Lz0yhXDoKG5ydAGIujK39em14I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=X9toLzj9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="X9toLzj9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B2ECC4CEED; Tue, 8 Jul 2025 16:36:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1751992575; bh=MvuQDNH0mc5mOoyR6j6P0tZwFdfbN2cVyha1il82h70=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X9toLzj987FYR00nsaBLGll7JZEb1lQxLaYJerOQeNF5mHqVId8qRYks1pZV5GxcE Hmazo3EYUurtboQj7CTN4HOWE5t7ni6FX84fwEuGu/tKZkZOOiZdURSrCIW/vh7+OF LcVNCncmsPtW9rzJLWaiFTEF8jaTMOzQjWyT0Gzo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shawn Guo , John Ernberg , stable , Jun Li , Xu Yang , Peter Chen Subject: [PATCH 6.6 116/132] usb: chipidea: udc: disconnect/reconnect from host when do suspend/resume Date: Tue, 8 Jul 2025 18:23:47 +0200 Message-ID: <20250708162233.952456341@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250708162230.765762963@linuxfoundation.org> References: <20250708162230.765762963@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xu Yang commit 31a6afbe86e8e9deba9ab53876ec49eafc7fd901 upstream. Shawn and John reported a hang issue during system suspend as below: - USB gadget is enabled as Ethernet - There is data transfer over USB Ethernet (scp a big file between host and device) - Device is going in/out suspend (echo mem > /sys/power/state) The root cause is the USB device controller is suspended but the USB bus is still active which caused the USB host continues to transfer data with device and the device continues to queue USB requests (in this case, a delayed TCP ACK packet trigger the issue) after controller is suspended, however the USB controller clock is already gated off. Then if udc driver access registers after that point, the system will hang. The correct way to avoid such issue is to disconnect device from host when the USB bus is not at suspend state. Then the host will receive disconnect event and stop data transfer in time. To continue make USB gadget device work after system resume, this will reconnect device automatically. To make usb wakeup work if USB bus is already at suspend state, this will keep connection for it only when USB device controller has enabled wakeup capability. Reported-by: Shawn Guo Reported-by: John Ernberg Closes: https://lore.kernel.org/linux-usb/aEZxmlHmjeWcXiF3@dragon/ Tested-by: John Ernberg # iMX8QXP Fixes: 235ffc17d014 ("usb: chipidea: udc: add suspend/resume support for device controller") Cc: stable Reviewed-by: Jun Li Signed-off-by: Xu Yang Acked-by: Peter Chen Link: https://lore.kernel.org/r/20250614124914.207540-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/chipidea/udc.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -2213,6 +2213,10 @@ static void udc_suspend(struct ci_hdrc * */ if (hw_read(ci, OP_ENDPTLISTADDR, ~0) == 0) hw_write(ci, OP_ENDPTLISTADDR, ~0, ~0); + + if (ci->gadget.connected && + (!ci->suspended || !device_may_wakeup(ci->dev))) + usb_gadget_disconnect(&ci->gadget); } static void udc_resume(struct ci_hdrc *ci, bool power_lost) @@ -2223,6 +2227,9 @@ static void udc_resume(struct ci_hdrc *c OTGSC_BSVIS | OTGSC_BSVIE); if (ci->vbus_active) usb_gadget_vbus_disconnect(&ci->gadget); + } else if (ci->vbus_active && ci->driver && + !ci->gadget.connected) { + usb_gadget_connect(&ci->gadget); } /* Restore value 0 if it was set for power lost check */