[U-Boot] Query on the ci_udc driver for USB client implementation

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

Hi Sanchayan,

> On Tuesday 04 November 2014 10:25 AM, Marek Vasut wrote:
> > On Monday, November 03, 2014 at 04:46:48 PM, Fabio Estevam wrote:
> >> On Mon, Nov 3, 2014 at 3:33 AM, Sanchayan Maity
> >>
> >> <maitysanchayan@gmail.com> wrote:
> >>> Hello,
> >>>
> >>> Any pointers?
> >>
> >> Adding Marek and Stefan on Cc in case they can provide some help.
> >>
> >> Regards,
> >>
> >> Fabio Estevam
> >>
> >>> Thanks & Regards,
> >>> Sanchayan Maity.
> >>>
> >>> On Thursday 30 October 2014 11:14 AM, Sanchayan Maity wrote:
> >>>> Hello,
> >>>>
> >>>> I am currently implementing USB Host and client support for
> >>>> Freescale Vybrid platform in u-boot. I managed to get the host
> >>>> implementation working.
> >>>>
> >>>> For the host side, usb start calls usb_init(), which in turns
> >>>> call, usb_lowlevel_init(), from there into the ehic_hcd_init()
> >>>> of my implementation. So, setting up the necessary clocks and
> >>>> plls for USB in my implementation and then setting up the
> >>>> usb_ehci, ehci_hccr and echi_hcor structures was all. The flow
> >>>> and setup required i was able to trace.
> >>>>
> >>>> The USB client part is not clear to me. I was thinking i can use
> >>>> the ci_udc driver somehow to implement the client part. How can
> >>>> i use the ci_udc driver to implement client functionality?. From
> >>>> what i could see, the usb_gadget_driver_register() is suppose to
> >>>> be the first call. But, i couldn't trace from where this gets
> >>>> called or the flow and setup is suppose to be. OR Is a separate
> >>>> client driver required and nothing generic can be used akin to
> >>>> how it could be done for host?
> > 
> > See include/configs/sansa_fuze_plus.h , you need the gadget driver
> > for the function you want to implement , in this case it's ethernet
> > for example (selected via CONFIG_USB_ETH_CDC ).
> > 
> > An example of DFU/UMS can be found in
> > include/configs/exynos4-common.h and to activate those, you need to
> > use the 'dfu' or 'ums' commands.
> 
> Thank you Marek. I had enabled usb ether options already and was
> trying to test USB client functionality with RNDIS. For some reason
> it was not working and i was not able to trace the issue and
> subsequently was not sure about the client part. Your inputs cleared
> my doubts. I tried UMS and DFU. UMS is working just fine and i can
> download the respective images through DFU. Though this DFU is not
> working full proof, but, i can figure that out now i feel. 

I'm very happy that UMS is working seamlessly. What kind of trouble do
you have with DFU?

> 
> Thanks again for your inputs. Cheers!
> 
> Best Regards,
> Sanchayan.
> 
> > 
> >>>> Sorry if i am asking this question in the wrong place. I
> >>>> couldn't find anyone in the u-boot IRC channel nor find
> >>>> something similar to the kernel-newbies mailing list.
> > 
> > There isn't any, so ask away ;-)
> > 
> >>>> Hope i am asking the right questions.
> > [...]
> > 
> > Best regards,
> > Marek Vasut
> > 



-- 
Best regards,

Lukasz Majewski

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