Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756198AbcJMXhy (ORCPT ); Thu, 13 Oct 2016 19:37:54 -0400 Received: from mail-pf0-f180.google.com ([209.85.192.180]:33909 "EHLO mail-pf0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754424AbcJMXhp (ORCPT ); Thu, 13 Oct 2016 19:37:45 -0400 From: John Stultz To: lkml Cc: Chen Yu , Wei Xu , Guodong Xu , Amit Pundir , Rob Herring , Mark Rutland , John Youn , Douglas Anderson , Greg Kroah-Hartman , linux-usb@vger.kernel.org, John Stultz Subject: [RFC][PATCH 1/2] usb: dwc2: Force port resume on switching to device mode Date: Thu, 13 Oct 2016 16:29:56 -0700 Message-Id: <1476401397-26497-2-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1476401397-26497-1-git-send-email-john.stultz@linaro.org> References: <1476401397-26497-1-git-send-email-john.stultz@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1665 Lines: 52 From: Chen Yu We've seen failures when switching between host and gadget mode, which was diagnosed as being caused due to the bus being auto-suspended when we switched. So this patch forces a port resume when switching to device mode if the bus is suspended. Cc: Wei Xu Cc: Guodong Xu Cc: Amit Pundir Cc: Rob Herring Cc: Mark Rutland Cc: John Youn Cc: Douglas Anderson Cc: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org Signed-off-by: Chen Yu Signed-off-by: John Stultz --- drivers/usb/dwc2/hcd.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index df5a065..b374e60 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -54,6 +54,9 @@ #include "core.h" #include "hcd.h" + +static void dwc2_port_resume(struct dwc2_hsotg *hsotg); + /* * ========================================================================= * Host Core Layer Functions @@ -3204,6 +3207,11 @@ static void dwc2_conn_id_status_change(struct work_struct *work) if (gotgctl & GOTGCTL_CONID_B) { /* Wait for switch to device mode */ dev_dbg(hsotg->dev, "connId B\n"); + if (hsotg->bus_suspended) { + dev_info(hsotg->dev, + "Do port resume before switching to device mode\n"); + dwc2_port_resume(hsotg); + } while (!dwc2_is_device_mode(hsotg)) { dev_info(hsotg->dev, "Waiting for Peripheral Mode, Mode=%s\n", -- 2.7.4