From patchwork Thu May 11 17:48:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elson Roy Serrao X-Patchwork-Id: 13238269 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 913E5C77B7C for ; Thu, 11 May 2023 17:48:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238516AbjEKRsq (ORCPT ); Thu, 11 May 2023 13:48:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238737AbjEKRsn (ORCPT ); Thu, 11 May 2023 13:48:43 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A3D381BEF; Thu, 11 May 2023 10:48:40 -0700 (PDT) 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 34BHlIfM007140; Thu, 11 May 2023 17:48:38 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=qcppdkim1; bh=0B5rEBl/+9BBL3AeebRXovzIGZ5bGGS24lRvyUenUOw=; b=jg6dgJeGO4ZIYaz5LXEBgUfprGF2tx7ecDY/a9LRwGPbB7PlvChxoWIX6LIR05NArfUF 40YtucJKVFauJsT8BiDw+IIVaA9HjkcVnhQAgBu2w3elELnk8Al/3TlcCoY19eAwhos+ 1OglBJTyuALiy/ECi57W8lsqzeth6WE2k1RXOZHnEq1FMQY4YhyhUdJ2XcXsn9ZLl+Po ura0dLdp1qYdeJVyIKU8ezS6/JBubEaGi39/3Q6G1PhA2iRqnSAIkjPFyR2JAgrSJ8Mi JApUhh6QEGSsO6HK4Hcjgtu19jpmiFD9Gp4WAYFTNvuycnIoUntmU5+hoPdKY2lsNzi+ 3g== Received: from nalasppmta01.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3qged2k0uf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 11 May 2023 17:48:37 +0000 Received: from pps.filterd (NALASPPMTA01.qualcomm.com [127.0.0.1]) by NALASPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTP id 34BHma1D023156; Thu, 11 May 2023 17:48:36 GMT Received: from pps.reinject (localhost [127.0.0.1]) by NALASPPMTA01.qualcomm.com (PPS) with ESMTP id 3qdfymgtqq-1; Thu, 11 May 2023 17:48:36 +0000 Received: from NALASPPMTA01.qualcomm.com (NALASPPMTA01.qualcomm.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 34BHma1T023005; Thu, 11 May 2023 17:48:36 GMT Received: from hu-devc-lv-c.qualcomm.com (hu-eserrao-lv.qualcomm.com [10.47.235.164]) by NALASPPMTA01.qualcomm.com (PPS) with ESMTP id 34BHmaCZ022857; Thu, 11 May 2023 17:48:36 +0000 Received: by hu-devc-lv-c.qualcomm.com (Postfix, from userid 464172) id 20D892036B; Thu, 11 May 2023 10:48:36 -0700 (PDT) From: Elson Roy Serrao To: gregkh@linuxfoundation.org, Thinh.Nguyen@synopsys.com Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, quic_wcheng@quicinc.com, quic_jackp@quicinc.com, Elson Roy Serrao Subject: [PATCH 1/2] usb: function: u_ether: Handle rx requests during suspend/resume Date: Thu, 11 May 2023 10:48:30 -0700 Message-Id: <1683827311-1462-2-git-send-email-quic_eserrao@quicinc.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1683827311-1462-1-git-send-email-quic_eserrao@quicinc.com> References: <1683827311-1462-1-git-send-email-quic_eserrao@quicinc.com> X-QCInternal: smtphost X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: PeLGhVnCV3a6YRRNbLllggYdkLmCHL8N X-Proofpoint-GUID: PeLGhVnCV3a6YRRNbLllggYdkLmCHL8N X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-05-11_14,2023-05-05_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 clxscore=1015 impostorscore=0 bulkscore=0 mlxscore=0 lowpriorityscore=0 phishscore=0 spamscore=0 malwarescore=0 mlxlogscore=999 adultscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000 definitions=main-2305110153 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Some UDCs might have a vote against runtime suspend if there is any request queued by the function driver. This would block the UDC driver to enter runtime suspend state when the host sends bus suspend notification. While tx requests get dequeued after completion, rx requests always remain queued for the next OUT data to be handled. Since during bus suspend scenario there are no active OUT transfers we can dequeue these requests when the function driver suspend callback gets called and queue them back during resume callback. Implement this mechanism by adding a new list for queued requests. Also move the gether_wakeup_host API to work queue context to better align with the remote wakeup op's synchronous operation. Signed-off-by: Elson Roy Serrao --- drivers/usb/gadget/function/u_ether.c | 47 +++++++++++++++++++++++++++-------- 1 file changed, 37 insertions(+), 10 deletions(-) diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c index 6956ad8..ce0a6a7 100644 --- a/drivers/usb/gadget/function/u_ether.c +++ b/drivers/usb/gadget/function/u_ether.c @@ -61,7 +61,7 @@ struct eth_dev { struct usb_gadget *gadget; spinlock_t req_lock; /* guard {rx,tx}_reqs */ - struct list_head tx_reqs, rx_reqs; + struct list_head tx_reqs, rx_reqs, rx_queued_reqs; atomic_t tx_qlen; struct sk_buff_head rx_frames; @@ -74,7 +74,7 @@ struct eth_dev { struct sk_buff *skb, struct sk_buff_head *list); - struct work_struct work; + struct work_struct work, wakeup_work; unsigned long todo; #define WORK_RX_MEMORY 0 @@ -212,7 +212,7 @@ rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags) if (skb) dev_kfree_skb_any(skb); spin_lock_irqsave(&dev->req_lock, flags); - list_add(&req->list, &dev->rx_reqs); + list_move_tail(&req->list, &dev->rx_reqs); spin_unlock_irqrestore(&dev->req_lock, flags); } return retval; @@ -302,7 +302,7 @@ static void rx_complete(struct usb_ep *ep, struct usb_request *req) if (!netif_running(dev->net)) { clean: spin_lock(&dev->req_lock); - list_add(&req->list, &dev->rx_reqs); + list_move_tail(&req->list, &dev->rx_reqs); spin_unlock(&dev->req_lock); req = NULL; } @@ -377,7 +377,7 @@ static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags) spin_lock_irqsave(&dev->req_lock, flags); while (!list_empty(&dev->rx_reqs)) { req = list_first_entry(&dev->rx_reqs, struct usb_request, list); - list_del_init(&req->list); + list_move_tail(&req->list, &dev->rx_queued_reqs); spin_unlock_irqrestore(&dev->req_lock, flags); if (rx_submit(dev, req, gfp_flags) < 0) { @@ -437,9 +437,11 @@ static inline int is_promisc(u16 cdc_filter) return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS; } -static int ether_wakeup_host(struct gether *port) +static void ether_wakeup_work(struct work_struct *w) { int ret; + struct eth_dev *dev = container_of(w, struct eth_dev, wakeup_work); + struct gether *port = dev->port_usb; struct usb_function *func = &port->func; struct usb_gadget *gadget = func->config->cdev->gadget; @@ -447,8 +449,6 @@ static int ether_wakeup_host(struct gether *port) ret = usb_func_wakeup(func); else ret = usb_gadget_wakeup(gadget); - - return ret; } static netdev_tx_t eth_start_xmit(struct sk_buff *skb, @@ -475,7 +475,7 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, DBG(dev, "Port suspended. Triggering wakeup\n"); netif_stop_queue(net); spin_unlock_irqrestore(&dev->lock, flags); - ether_wakeup_host(dev->port_usb); + schedule_work(&dev->wakeup_work); return NETDEV_TX_BUSY; } @@ -753,8 +753,10 @@ struct eth_dev *gether_setup_name(struct usb_gadget *g, spin_lock_init(&dev->lock); spin_lock_init(&dev->req_lock); INIT_WORK(&dev->work, eth_work); + INIT_WORK(&dev->wakeup_work, ether_wakeup_work); INIT_LIST_HEAD(&dev->tx_reqs); INIT_LIST_HEAD(&dev->rx_reqs); + INIT_LIST_HEAD(&dev->rx_queued_reqs); skb_queue_head_init(&dev->rx_frames); @@ -824,8 +826,10 @@ struct net_device *gether_setup_name_default(const char *netname) spin_lock_init(&dev->lock); spin_lock_init(&dev->req_lock); INIT_WORK(&dev->work, eth_work); + INIT_WORK(&dev->wakeup_work, ether_wakeup_work); INIT_LIST_HEAD(&dev->tx_reqs); INIT_LIST_HEAD(&dev->rx_reqs); + INIT_LIST_HEAD(&dev->rx_queued_reqs); skb_queue_head_init(&dev->rx_frames); @@ -1040,7 +1044,9 @@ EXPORT_SYMBOL_GPL(gether_set_ifname); void gether_suspend(struct gether *link) { struct eth_dev *dev = link->ioport; + struct usb_request *req; unsigned long flags; + int status; if (!dev) return; @@ -1050,9 +1056,20 @@ void gether_suspend(struct gether *link) * There is a transfer in progress. So we trigger a remote * wakeup to inform the host. */ - ether_wakeup_host(dev->port_usb); + schedule_work(&dev->wakeup_work); return; } + /* Dequeue the submitted requests. */ + spin_lock(&dev->req_lock); + while (!list_empty(&dev->rx_queued_reqs)) { + req = list_last_entry(&dev->rx_queued_reqs, struct usb_request, list); + list_move_tail(&req->list, &dev->rx_reqs); + spin_unlock(&dev->req_lock); + status = usb_ep_dequeue(dev->port_usb->out_ep, req); + spin_lock(&dev->req_lock); + } + spin_unlock(&dev->req_lock); + spin_lock_irqsave(&dev->lock, flags); link->is_suspend = true; spin_unlock_irqrestore(&dev->lock, flags); @@ -1067,6 +1084,7 @@ void gether_resume(struct gether *link) if (!dev) return; + defer_kevent(dev, WORK_RX_MEMORY); if (netif_queue_stopped(dev->net)) netif_start_queue(dev->net); @@ -1228,6 +1246,15 @@ void gether_disconnect(struct gether *link) usb_ep_free_request(link->out_ep, req); spin_lock(&dev->req_lock); } + + while (!list_empty(&dev->rx_queued_reqs)) { + req = list_first_entry(&dev->rx_queued_reqs, struct usb_request, list); + list_del(&req->list); + + spin_unlock(&dev->req_lock); + usb_ep_free_request(link->out_ep, req); + spin_lock(&dev->req_lock); + } spin_unlock(&dev->req_lock); link->out_ep->desc = NULL;