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=ham 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 3130CC3A5A8 for ; Wed, 4 Sep 2019 18:12:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 089E02341D for ; Wed, 4 Sep 2019 18:12:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620755; bh=dtdFH06IsEHUIClj6Ic3CcPM+EVe3SGjsswJfSGmSVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=D3xJinKbdpEQ+PsD/LRvY3DbShfFjgxNjkhzABJahceMPzfh45aheBme34avqbsbW Epf44t3RB/q0/uSOWg6+xGNpZ6QofpMWmNibUcz0DbJNNy+CKwCokNebTehzAuF4hJ EfJDDTuISH0C2vgVg4d5MdQvbFXu7eUZ1tnZB9U0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389792AbfIDSMe (ORCPT ); Wed, 4 Sep 2019 14:12:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:57006 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733228AbfIDSMd (ORCPT ); Wed, 4 Sep 2019 14:12:33 -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 5A3D022CEA; Wed, 4 Sep 2019 18:12:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620752; bh=dtdFH06IsEHUIClj6Ic3CcPM+EVe3SGjsswJfSGmSVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lw9x+g7IAdkBXOTm1KQNZdlgfXMmUS4g+pryr/ktl13wTKewc0WUF6nyrjXJSdY2N BnBHQpHzs7TanxMd9XCP/jf5MNReX+LX7ITIcTaTqINs3LNRENZL9wTI3GXqSSbfTe Qgo72nBVXSTaQmhhgcSbmUVDMO0fPXzimFbOBoqo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Chen Subject: [PATCH 5.2 082/143] usb: chipidea: udc: dont do hardware access if gadget has stopped Date: Wed, 4 Sep 2019 19:53:45 +0200 Message-Id: <20190904175317.271965485@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904175314.206239922@linuxfoundation.org> References: <20190904175314.206239922@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; } @@ -1303,6 +1303,10 @@ 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 */ @@ -1392,6 +1396,10 @@ 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; @@ -1415,8 +1423,8 @@ 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); @@ -1487,6 +1495,10 @@ 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); @@ -1559,6 +1571,10 @@ 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;