From patchwork Wed Dec 6 20:18:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 752478 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="ESVOeUxW" Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68CC512F; Wed, 6 Dec 2023 12:22:08 -0800 (PST) Received: from pps.filterd (m0279872.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3B6KFAIB010863; Wed, 6 Dec 2023 20:22:06 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=qcppdkim1; bh=sRFsmyZ5qCKqzCrtUBDojqShJ00B0aVgG3aZXs2KlE4=; b=ESVOeUxWTe6/3ftOvnw6+zTd3QKLab5VKiNWeeKoyuC0T/jvSRech3W4Fv9YddMUj8zL 7/N+9JzA/t44EFIh6dzSXC7Z//Q5pRwvQnLm8vFlNphxZy4vP6SkiPoaxZBAe4XngedH qoqxQxOXm2LQkapvVheSUYP5OPAGIG2046xTq0fGQycWM9P70ChWXpctwW2bkXRXuBoB 5rHDHmtF9kyj91zc93kFGy6tA/edaIUeTlNEGeTP4QgGW/VUue6e7XjS3rzntE6vzhzb gG1eIMUc9retXWF3tsuYCJpN3mrUCi/bwvSz5yvywmOCoEorOfHeR+pNyp3lFFxKcbLl jQ== Received: from nalasppmta05.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3ute972sxq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 Dec 2023 20:22:05 +0000 Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA05.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 3B6KM4qm020081 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 6 Dec 2023 20:22:04 GMT Received: from hu-wcheng-lv.qualcomm.com (10.49.16.6) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Wed, 6 Dec 2023 12:18:23 -0800 From: Wesley Cheng To: , CC: , , Wesley Cheng Subject: [PATCH v2] usb: dwc3: gadget: Handle EP0 request dequeuing properly Date: Wed, 6 Dec 2023 12:18:14 -0800 Message-ID: <20231206201814.32664-1-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nalasex01b.na.qualcomm.com (10.47.209.197) To nalasex01b.na.qualcomm.com (10.47.209.197) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: PNCx_rXno8R_zFuD3BpWwxveGnampAtT X-Proofpoint-ORIG-GUID: PNCx_rXno8R_zFuD3BpWwxveGnampAtT X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-06_16,2023-12-06_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 priorityscore=1501 adultscore=0 impostorscore=0 suspectscore=0 mlxscore=0 malwarescore=0 phishscore=0 bulkscore=0 lowpriorityscore=0 spamscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000 definitions=main-2312060140 Current EP0 dequeue path will share the same as other EPs. However, there are some special considerations that need to be made for EP0 transfers: - EP0 transfers never transition into the started_list - EP0 only has one active request at a time In case there is a vendor specific control message for a function over USB FFS, then there is no guarantee on the timeline which the DATA/STATUS stage is responded to. While this occurs, any attempt to end transfers on non-control EPs will end up having the DWC3_EP_DELAY_STOP flag set, and defer issuing of the end transfer command. If the USB FFS application decides to timeout the control transfer, or if USB FFS AIO path exits, the USB FFS driver will issue a call to usb_ep_dequeue() for the ep0 request. In case of the AIO exit path, the AIO FS blocks until all pending USB requests utilizing the AIO path is completed. However, since the dequeue of ep0 req does not happen properly, all non-control EPs with the DWC3_EP_DELAY_STOP flag set will not be handled, and the AIO exit path will be stuck waiting for the USB FFS data endpoints to receive a completion callback. Fix is to utilize dwc3_ep0_reset_state() in the dequeue API to ensure EP0 is brought back to the SETUP state, and ensures that any deferred end transfer commands are handled. This also will end any active transfers on EP0, compared to the previous implementation which directly called giveback only. Fixes: fcd2def66392 ("usb: dwc3: gadget: Refactor dwc3_gadget_ep_dequeue") Signed-off-by: Wesley Cheng Acked-by: Thinh Nguyen --- Changes from v1: - Added fixes tag drivers/usb/dwc3/gadget.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 858fe4c299b7..88d8d589f014 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2103,7 +2103,17 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep, list_for_each_entry(r, &dep->pending_list, list) { if (r == req) { - dwc3_gadget_giveback(dep, req, -ECONNRESET); + /* + * Explicitly check for EP0/1 as dequeue for those + * EPs need to be handled differently. Control EP + * only deals with one USB req, and giveback will + * occur during dwc3_ep0_stall_and_restart(). EP0 + * requests are never added to started_list. + */ + if (dep->number > 1) + dwc3_gadget_giveback(dep, req, -ECONNRESET); + else + dwc3_ep0_reset_state(dwc); goto out; } }