From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05AFBC3A5A8 for ; Wed, 4 Sep 2019 18:24:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0CF220882 for ; Wed, 4 Sep 2019 18:24:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567621468; bh=HmqFCPFCKaJpoZao2sHYtfAsKC5MuJ2xbU/4FCfXwvU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kfGOKHIzPzcIPFQcRzgaR1sWx4RTk9Jsc5AJ7a8EnZyAMFvD+KMb3Uj9VIFK1SfWt sVt4GMHf07xQMSeQSasRvT/IEAZDCIohHONu3CzCY7KuMZr5E/NP0PSowGoSBad1Db qpyT46xkZpizt2UdvxeTa1eumAPHifyjMoLXfJ/0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732587AbfIDSB2 (ORCPT ); Wed, 4 Sep 2019 14:01:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:41008 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387984AbfIDSB1 (ORCPT ); Wed, 4 Sep 2019 14:01:27 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8B9D42341E; Wed, 4 Sep 2019 18:01:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620087; bh=HmqFCPFCKaJpoZao2sHYtfAsKC5MuJ2xbU/4FCfXwvU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MP9ulvXZfFe7dYsRF4f2NMP8K28FubBVo9cUIOGS9T0bdMMAti/dCjtEBAyHLZKlR UyIpQzAZ3nI6Tu6ccK89vvzMT3xUqJ+T0Qxr5nZ3L0X9Np7gCZz1pT/acs2GUbr0id J9C0oSQI8SyFNjM/ih5ukfC6wv1ogrGM6DU6n+C8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Chen Subject: [PATCH 4.9 67/83] usb: chipidea: udc: dont do hardware access if gadget has stopped Date: Wed, 4 Sep 2019 19:53:59 +0200 Message-Id: <20190904175309.517424909@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904175303.488266791@linuxfoundation.org> References: <20190904175303.488266791@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peter Chen commit cbe85c88ce80fb92956a0793518d415864dcead8 upstream. After _gadget_stop_activity is executed, we can consider the hardware operation for gadget has finished, and the udc can be stopped and enter low power mode. So, any later hardware operations (from usb_ep_ops APIs or usb_gadget_ops APIs) should be considered invalid, any deinitializatons has been covered at _gadget_stop_activity. I meet this problem when I plug out usb cable from PC using mass_storage gadget, my callstack like: vbus interrupt->.vbus_session-> composite_disconnect ->pm_runtime_put_sync(&_gadget->dev), the composite_disconnect will call fsg_disable, but fsg_disable calls usb_ep_disable using async way, there are register accesses for usb_ep_disable. So sometimes, I get system hang due to visit register without clock, sometimes not. The Linux Kernel USB maintainer Alan Stern suggests this kinds of solution. See: http://marc.info/?l=linux-usb&m=138541769810983&w=2. Cc: #v4.9+ Signed-off-by: Peter Chen Link: https://lore.kernel.org/r/20190820020503.27080-2-peter.chen@nxp.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/chipidea/udc.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -709,12 +709,6 @@ static int _gadget_stop_activity(struct struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget); unsigned long flags; - spin_lock_irqsave(&ci->lock, flags); - ci->gadget.speed = USB_SPEED_UNKNOWN; - ci->remote_wakeup = 0; - ci->suspended = 0; - spin_unlock_irqrestore(&ci->lock, flags); - /* flush all endpoints */ gadget_for_each_ep(ep, gadget) { usb_ep_fifo_flush(ep); @@ -732,6 +726,12 @@ static int _gadget_stop_activity(struct ci->status = NULL; } + spin_lock_irqsave(&ci->lock, flags); + ci->gadget.speed = USB_SPEED_UNKNOWN; + ci->remote_wakeup = 0; + ci->suspended = 0; + spin_unlock_irqrestore(&ci->lock, flags); + return 0; } @@ -1306,6 +1306,10 @@ static int ep_disable(struct usb_ep *ep) return -EBUSY; spin_lock_irqsave(hwep->lock, flags); + if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) { + spin_unlock_irqrestore(hwep->lock, flags); + return 0; + } /* only internal SW should disable ctrl endpts */ @@ -1395,6 +1399,10 @@ static int ep_queue(struct usb_ep *ep, s return -EINVAL; spin_lock_irqsave(hwep->lock, flags); + if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) { + spin_unlock_irqrestore(hwep->lock, flags); + return 0; + } retval = _ep_queue(ep, req, gfp_flags); spin_unlock_irqrestore(hwep->lock, flags); return retval; @@ -1418,8 +1426,8 @@ static int ep_dequeue(struct usb_ep *ep, return -EINVAL; spin_lock_irqsave(hwep->lock, flags); - - hw_ep_flush(hwep->ci, hwep->num, hwep->dir); + if (hwep->ci->gadget.speed != USB_SPEED_UNKNOWN) + hw_ep_flush(hwep->ci, hwep->num, hwep->dir); list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) { dma_pool_free(hwep->td_pool, node->ptr, node->dma); @@ -1490,6 +1498,10 @@ static void ep_fifo_flush(struct usb_ep } spin_lock_irqsave(hwep->lock, flags); + if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) { + spin_unlock_irqrestore(hwep->lock, flags); + return; + } hw_ep_flush(hwep->ci, hwep->num, hwep->dir); @@ -1558,6 +1570,10 @@ static int ci_udc_wakeup(struct usb_gadg int ret = 0; spin_lock_irqsave(&ci->lock, flags); + if (ci->gadget.speed == USB_SPEED_UNKNOWN) { + spin_unlock_irqrestore(&ci->lock, flags); + return 0; + } if (!ci->remote_wakeup) { ret = -EOPNOTSUPP; goto out;