[U-Boot] [PATCH] usb: gadget: composite: Correct recovery path for register

[Lukasz Majewski <l.majewski@samsung.com>]

Hi Marek,

> On 02/29/2016 11:11 AM, Lukasz Majewski wrote:
> > Hi Marek,
> > 
> >> On 02/26/2016 08:43 PM, Sam Protsenko wrote:
> >>> On Fri, Feb 19, 2016 at 9:34 PM, Sam Protsenko
> >>> <semen.protsenko@linaro.org> wrote:
> >>>> + Praneeth Bajjuri
> >>>> + Tom Rini
> >>>> + Rob Herring
> >>>>
> >>>> On Tue, Feb 16, 2016 at 7:59 PM, Semen Protsenko
> >>>> <semen.protsenko@linaro.org> wrote:
> >>>>> From: Sam Protsenko <semen.protsenko@linaro.org>
> >>>>>
> >>>>> In case when usb_composite_register() failed once (for whatever
> >>>>> reason), it will fail further even if all conditions are
> >>>>> correct. Example:
> >>>>>
> >>>>>     => fastboot 2
> >>>>>     Invalid Controller Index
> >>>>>     couldn't find an available UDC
> >>>>>     g_dnl_register: failed!, error: -19
> >>>>>     exit not allowed from main input shell.
> >>>>>
> >>>>>     => fastboot 0
> >>>>>     g_dnl_register: failed!, error: -22
> >>>>>     exit not allowed from main input shell.
> >>>>>
> >>>>> Despite that 0 is correct index for USB controller, "fastboot 0"
> >>>>> command will fail, because "composite" structure wasn't cleared
> >>>>> properly on previous fail (on "fastboot 2" command).
> >>>>>
> >>>>> This patch fixes that erroneous behavior, allowing us to use
> >>>>> composite even after previous failure.
> >>>>>
> >>>>> Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
> >>>>> ---
> >>>>>  drivers/usb/gadget/composite.c | 8 +++++++-
> >>>>>  1 file changed, 7 insertions(+), 1 deletion(-)
> >>>>>
> >>>>> diff --git a/drivers/usb/gadget/composite.c
> >>>>> b/drivers/usb/gadget/composite.c index 60f9272..d0ee784 100644
> >>>>> --- a/drivers/usb/gadget/composite.c
> >>>>> +++ b/drivers/usb/gadget/composite.c
> >>>>> @@ -1077,6 +1077,8 @@ static struct usb_gadget_driver
> >>>>> composite_driver = { */
> >>>>>  int usb_composite_register(struct usb_composite_driver *driver)
> >>>>>  {
> >>>>> +       int res;
> >>>>> +
> >>>>>         if (!driver || !driver->dev || !driver->bind ||
> >>>>> composite) return -EINVAL;
> >>>>>
> >>>>> @@ -1084,7 +1086,11 @@ int usb_composite_register(struct
> >>>>> usb_composite_driver *driver) driver->name = "composite";
> >>>>>         composite = driver;
> >>>>>
> >>>>> -       return usb_gadget_register_driver(&composite_driver);
> >>>>> +       res = usb_gadget_register_driver(&composite_driver);
> >>>>> +       if (res != 0)
> >>>>> +               composite = NULL;
> >>>>> +
> >>>>> +       return res;
> >>>>>  }
> >>>>>
> >>>>>  /**
> >>>>> --
> >>>>> 2.7.0
> >>>>>
> >>>
> >>> bump
> >>>
> >>
> >> Looks fine. Lukasz, shall I pick this myself ?
> >>
> >> btw if this isn't applied in a week, please ping me and I will
> >> pick it nonetheless.
> >>
> > 
> > I will add this to my tree. And test it afterwards. 

This patch seems correct - no regression found.

Tested-by: Lukasz Majewski "<l.majewski@samsung.com>"
Acked-by: Lukasz Majewski "<l.majewski@samsung.com>"

> > 
> > I will send new PR with some other patches.

Patches which I thought that you didn't pull are already in u-boot-usb
tree, so there is no point to prepare PR for this single patch.

Hence, Marek, please apply it directly to -usb tree.

> > 
> 
> Roger, thanks!
> 



-- 
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group