From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751323AbbJTGKU (ORCPT ); Tue, 20 Oct 2015 02:10:20 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:63133 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750787AbbJTGKS (ORCPT ); Tue, 20 Oct 2015 02:10:18 -0400 Message-ID: <5625DA7E.8000601@mentor.com> Date: Tue, 20 Oct 2015 15:09:02 +0900 From: Jiada Wang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Peter Chen CC: , , Subject: Re: [PATCH] usb: chipidea: udc: clear vbus_active flag in udc_stop References: <1445308158-23100-1-git-send-email-jiada_wang@mentor.com> <20151020060107.GA27364@shlinux2> In-Reply-To: <20151020060107.GA27364@shlinux2> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi On 10/20/2015 03:01 PM, Peter Chen wrote: > On Tue, Oct 20, 2015 at 11:29:18AM +0900, Jiada Wang wrote: >> Currently in udc_stop, if vbus_active flag is true, all USB activities >> will be stopped, but vbus_active flag is still left to be true, >> this causes issue, when afterwards driver tries to connect gadget >> device to host, But due to the uncleared vbus_active, some necessary >> setup steps are skipped. >> >> This patch clears vbus_active flag in udc_stop callback. >> >> Signed-off-by: Jiada Wang >> --- >> drivers/usb/chipidea/udc.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c >> index 8223fe7..b9ac228 100644 >> --- a/drivers/usb/chipidea/udc.c >> +++ b/drivers/usb/chipidea/udc.c >> @@ -1762,6 +1762,7 @@ static int ci_udc_stop(struct usb_gadget *gadget) >> spin_lock_irqsave(&ci->lock, flags); >> >> if (ci->vbus_active) { >> + ci->vbus_active = 0; >> hw_device_state(ci, 0); >> if (ci->platdata->notify_event) >> ci->platdata->notify_event(ci, >> -- >> 2.4.5 >> > > This flag will be handled by vbus interrupt, would you please explain > more what problem you have met? the actual issue I had is, build kernel with USB_OTG_FSM enabled, keep usb cable plugged, load/unload USB gadget module (for example I tried g_zero or g_serial), after unload gadget module once, then the status of vbus_active is not correct, this causes host machine failed to detect gadget device when later gadget device module is loaded again. Thanks, Jiada >