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

[John Stultz]

On Tue, Oct 17, 2017 at 1:41 AM, Minas Harutyunyan
<Minas.Harutyunyan@xxxxxxxxxxxx> wrote:
> On 10/17/2017 1:34 AM, John Stultz wrote:
>> On Mon, Oct 16, 2017 at 1:36 AM, Minas Harutyunyan
>> <Minas.Harutyunyan@xxxxxxxxxxxx> 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 1âb1."
>>>
>>> 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.

Correct. On B unplug, I see:
dwc2_handle_conn_id_status_change_intr: ++Connector ID Status Change
Interrupt++  (Host)

And I never see any calls to dwc2_handle_otg_intr().

> 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?

So this is what I expect, but I don't see it. Since without my patch,
nothing seems to call disconenct when the B plug is disconnected, I
still see:
  # cat /sys/class/udc/f72c0000.usb/state
  configured

thanks
-john