[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <5099a06b-b0b9-348d-4043-141d96c55bb7@synopsys.com>
Date: Tue, 25 Oct 2016 15:14:01 -0700
From: John Youn <John.Youn@...opsys.com>
To: John Stultz <john.stultz@...aro.org>,
John Youn <John.Youn@...opsys.com>
CC: lkml <linux-kernel@...r.kernel.org>, Wei Xu <xuwei5@...ilicon.com>,
Guodong Xu <guodong.xu@...aro.org>,
Chen Yu <chenyu56@...wei.com>,
"Amit Pundir" <amit.pundir@...aro.org>,
Rob Herring <robh+dt@...nel.org>,
"Mark Rutland" <mark.rutland@....com>,
Douglas Anderson <dianders@...omium.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
"linux-usb@...r.kernel.org" <linux-usb@...r.kernel.org>
Subject: Re: [RFC][PATCH] usb: dwc2: Make sure we disconnect the gadget state
on reset
On 10/25/2016 2:56 PM, John Stultz wrote:
> On Tue, Oct 25, 2016 at 2:29 PM, John Youn <John.Youn@...opsys.com> wrote:
>> On 10/19/2016 11:00 PM, John Stultz wrote:
>>> I had seen some odd behavior with HiKey's usb-gadget interface
>>> that I finally seemed to have chased down. Basically every other
>>> time I pluged in the OTG port, the gadget interface would
>>> properly initialize. The other times, I'd get a big WARN_ON
>>> in dwc2_hsotg_init_fifo() about the fifo_map not being clear.
>>>
>>> Ends up If we don't disconnect the gadget state on reset, the
>>> fifo-map doesn't get cleared properly, which causes WARN_ON
>>> messages and also results in the device not properly being
>>> setup as a gadget every other time the OTG port is connected.
>>>
>>> So this patch adds a call to dwc2_hsotg_disconnect() in the
>>> reset path so the state is properly cleared.
>>>
>>> With it, the gadget interface initializes properly on every
>>> plug in.
>>>
>>> I don't know if this is actually the right fix, but it seems
>>> to work well. Feedback would be greatly appreciated!
>>>
>>> Cc: Wei Xu <xuwei5@...ilicon.com>
>>> Cc: Guodong Xu <guodong.xu@...aro.org>
>>> Cc: Chen Yu <chenyu56@...wei.com>
>>> Cc: Amit Pundir <amit.pundir@...aro.org>
>>> Cc: Rob Herring <robh+dt@...nel.org>
>>> Cc: Mark Rutland <mark.rutland@....com>
>>> Cc: John Youn <johnyoun@...opsys.com>
>>> Cc: Douglas Anderson <dianders@...omium.org>
>>> Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
>>> Cc: linux-usb@...r.kernel.org
>>> Signed-off-by: John Stultz <john.stultz@...aro.org>
>>> ---
>>> drivers/usb/dwc2/gadget.c | 2 ++
>>> 1 file changed, 2 insertions(+)
>>>
>>> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
>>> index 24fbebc..5505001 100644
>>> --- a/drivers/usb/dwc2/gadget.c
>>> +++ b/drivers/usb/dwc2/gadget.c
>>> @@ -2519,6 +2519,8 @@ void dwc2_hsotg_core_init_disconnected(struct dwc2_hsotg *hsotg,
>>>
>>> /* Kill any ep0 requests as controller will be reinitialized */
>>> kill_all_requests(hsotg, hsotg->eps_out[0], -ECONNRESET);
>>> + /* Make sure everything is disconnected */
>>> + dwc2_hsotg_disconnect(hsotg);
>>>
>>> if (!is_usb_reset)
>>> if (dwc2_core_reset(hsotg))
>>>
>>
>> Seems fine with our testing.
>>
>> Acked-by: John Youn <johnyoun@...opsys.com>
>
> Awesome! Thanks so much for the review and testing!
>
> I'm curious, did you happen to have any thoughts or objections on the
> "dwc2: Force port resume on switching to device mode" patch
> (https://patchwork.kernel.org/patch/9375965/ ) as well?
Sorry, must have missed that one. We'll take a look.
Regards,
John
Powered by blists - more mailing lists