From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Szyprowski Subject: Re: [PATCH 3/9] usb: dwc2/gadget: fix support for soft_connect udc framework feature Date: Fri, 17 Oct 2014 12:43:48 +0200 Message-ID: <5440F2E4.3030901@samsung.com> References: <1413464285-24172-1-git-send-email-m.szyprowski@samsung.com> <1413464285-24172-4-git-send-email-m.szyprowski@samsung.com> <20141016133610.GH3480@saruman> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mailout3.w1.samsung.com ([210.118.77.13]:34661 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751632AbaJQKnv (ORCPT ); Fri, 17 Oct 2014 06:43:51 -0400 In-reply-to: <20141016133610.GH3480@saruman> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: balbi@ti.com Cc: linux-usb@vger.kernel.org, linux-samsung-soc@vger.kernel.org, Kyungmin Park , Robert Baldyga , Paul Zimmerman , Krzysztof Kozlowski Hello, On 2014-10-16 15:36, Felipe Balbi wrote: > On Thu, Oct 16, 2014 at 02:57:59PM +0200, Marek Szyprowski wrote: >> Enabling and disabling usb gadget by writing to >> /sys/class/udc/*hsotg/soft_connect results in calling udc_start/udc_stop >> functions with the same usb gadget driver, so the driver should not WARN >> about such case. >> >> Signed-off-by: Marek Szyprowski >> --- >> drivers/usb/dwc2/gadget.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c >> index 8870e38c1d82..37fda4c03397 100644 >> --- a/drivers/usb/dwc2/gadget.c >> +++ b/drivers/usb/dwc2/gadget.c >> @@ -2892,7 +2892,7 @@ static int s3c_hsotg_udc_start(struct usb_gadget *gadget, >> return -EINVAL; >> } >> >> - WARN_ON(hsotg->driver); >> + WARN_ON(hsotg->driver && hsotg->driver != driver); > the bug is in your ->udc_stop(). You should clear hsotg->driver to NULL > there. Ok, I will change udc_stop() to always zero hsotg->driver, like other udc drivers. I was a bit confused by the fact that udc core passes driver to udc_stop(), when called from soft_connect and NULL on gadget removal. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland