Re: [PATCH] usb: gadget: udc-core: call udc_stop() before gadget unbind

[Felipe Balbi]

On Mon, Dec 29, 2014 at 08:30:04AM +0100, Robert Baldyga wrote:
> Hi Felipe,
> 
> On 12/23/2014 07:31 PM, Felipe Balbi wrote:
> > On Tue, Dec 23, 2014 at 07:34:15AM +0100, Robert Baldyga wrote:
> >> On 12/22/2014 05:34 PM, Felipe Balbi wrote:
> >>> On Mon, Dec 15, 2014 at 11:05:22AM +0100, Robert Baldyga wrote:
> >>>> On 12/15/2014 06:13 AM, Peter Chen wrote:
> >>>>> On Fri, Dec 12, 2014 at 02:17:28PM +0100, Robert Baldyga wrote:
> >>>>>> As usb function drivers assumes that all usb request will be completed
> >>>>>> before function unbind call, we should supply such behavior. In some
> >>>>>> cases ep_disable() won't kill all request effectively, because some
> >>>>>> IN requests can be in running state. In such situation it's possible
> >>>>>> to have unbind function called before last request completion, which
> >>>>>> can cause problems.
> >>>>>
> >>>>> Doesn't the function's disable/unbind should call usb_ep_dequeue to make
> >>>>> sure the transfer has ended?
> >>>>
> >>>> USB function drivers like ECM or HID surely doesn't. It looks like
> >>>> there's assumption that all requests will be completed by UDC driver.
> >>>
> >>> that's a bug on those drivers :-)
> >>
> >> So we can't make assumptions that requests will be completed in
> >> ep_disable()?
> > 
> > oh, no you can. I misread it.
> > 
> >>>> Function ep_disable() should complete requests in hardware driver, but
> >>>> at least in DWC2 driver not all requests are completed at this stage
> >>>
> >>> and that's a bug on dwc2 :-)
> >>
> >> I have already found that out. Another UDC drivers simply kill all
> >> request without waiting for currently running, so I did the same in
> >> DWC2. Here is my patch:
> >> http://www.spinics.net/lists/linux-usb/msg118698.html
> > 
> > should be in my pull request already.
> 
> It looks like you applied wrong patch. I meant patch titled "drivers:
> usb: dwc2: remove 'force' parameter from kill_all_requests()" is the
> latest and complete fix. The patch you have applied named "usb: dwc2:
> gadget: kill requests with 'force' in s3c_hsotg_udc_stop()" do not solve
> problem completely without changes in udc-core, which we concluded are
> not acceptable.
> 
> Sorry for the mess. I understand that titles of both patches are
> confusing similar.

Can you send a patch on top fixing things up ? Either that or a revert
followed by correct patch.

-- 
balbi

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