Re: [RESEND x2][PATCH 0/3] dwc2 fixes for edge cases on hikey

From: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
To: John Stultz <john.stultz@linaro.org>,
	Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Cc: John Youn <John.Youn@synopsys.com>,
	lkml <linux-kernel@vger.kernel.org>,
	Wei Xu <xuwei5@hisilicon.com>, Guodong Xu <guodong.xu@linaro.org>,
	"Amit Pundir" <amit.pundir@linaro.org>,
	YongQin Liu <yongqin.liu@linaro.org>,
	Douglas Anderson <dianders@chromium.org>,
	Chen Yu <chenyu56@huawei.com>,
	Felipe Balbi <felipe.balbi@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>
Subject: Re: [RESEND x2][PATCH 0/3] dwc2 fixes for edge cases on hikey
Date: Tue, 17 Oct 2017 08:41:08 +0000	[thread overview]
Message-ID: <410670D7E743164D87FA6160E7907A560113A2ECC2@am04wembxa.internal.synopsys.com> (raw)
In-Reply-To: CALAqxLV71UvLtZU=MYwgVmuGU-hV+hs5jFy09AgvihJWQBEkmA@mail.gmail.com

On 10/17/2017 1:34 AM, John Stultz wrote:
> On Mon, Oct 16, 2017 at 1:36 AM, Minas Harutyunyan
> <Minas.Harutyunyan@synopsys.com> wrote:
>> On b-plug disconnect should asserted GOTGINT.SesEndDet interrupt.
>> According previously sent by you register dump (GHWCFG2 = 0x23affc70)
>> your core OTG_MODE=0.
>> Bellow fragment from programming guide on Device disconnect:
>>
>> "7.3Device Disconnection
>> The device session ends when the USB cable is disconnected or if the
>> VBUS is switched off by the Host. The
>> device disconnect flow varies depending on the value of the OTG_MODE
>> configuration parameter.
>>
>> When OTG_MODE = 0,1, or 3
>> When OTG_MODE is set to 0,1, or 3, the device disconnect flow is as follows:
>> 1. When the USB cable is unplugged or when the VBUS is switched off by
>> the Host, the Device core
>> trigger GINTSTS.OTGInt [bit 2] interrupt bit.
>> 2. When the device application detects GINTSTS.OTGInt interrupt, it
>> checks that the
>> GOTGINT.SesEndDet (Session End Detected) bit is set to 1’b1."
>>
>> So, you should receive and handle "Session End Detected". In function
>> dwc2_handle_otg_intr() on this interrupt (in device mode) calling
>> dwc2_hsotg_disconnect() function. By adding your patch "[PATCH 3/3] usb:
>> dwc2: Fix UDC state tracking" state changed to not attached as required.
> 
> 
> So, on the HiKey board (using 4.14-rc5 + Vardan's patch), I'm not
> seeing the GOTGINT_SES_END_DET in dwc2_handle_otg_intr() when I remove
> the USB OTG cable.
> 
> In fact, I'm not seeing any calls to dwc2_handle_otg_intr()... which
> seems... odd maybe?  Any clues as to what might be going wrong then?
> 
> thanks
> -john
> 
Hi John Stultz,
So, on Hikey board on unplug B connector GOTGINT.SesEndDet interrupt not 
asserted, instead asserted GINTSTS_CONIDSTSCHNG. Please, confirm.

In this case without your patch "[PATCH 1/3] usb: dwc2: Improve gadget 
state disconnection handling" but by applying your patch "[PATCH 3/3] 
usb: dwc2: Fix UDC state tracking":
1. On B plug connect UDC state will be set to "configured"
2. On B plug disconnect - "not attached".
Is it Ok for you?

Meantime, I'll check with HW team why GOTGINT.SesEndDet interrupt not 
asserted on unplug B connector.

Thanks,
Minas