[U-Boot] [PATCH v7] USB: Add generic ULPI layer and a viewport

[Igor Grinberg]

Hi Marek,

On 12/07/11 19:27, Marek Vasut wrote:
>> On 12/07/11 03:42, Simon Glass wrote:
>>> Hi Igor,
>>>
>>> Looks good - a few comments from me.
>>>
>>> On Mon, Dec 5, 2011 at 1:07 AM, Igor Grinberg <grinberg at compulab.co.il> 
> wrote:
>>>> From: Jana Rapava <fermata7 at gmail.com>
>>>>
>>>> Add partial ULPI specification implementation that should be enough to
>>>> interface the ULPI PHYs in the boot loader context.
>>>> Add a viewport implementation for Chipidea/ARC based controllers.
>>>>
>>>> Signed-off-by: Jana Rapava <fermata7 at gmail.com>
>>>> Signed-off-by: Igor Grinberg <grinberg at compulab.co.il>
>>>> Cc: Remy Bohmer <linux at bohmer.net>
>>>> Cc: Stefano Babic <sbabic at denx.de>
>>>> Cc: Wolfgang Grandegger <wg at denx.de>
>>>> Cc: Simon Glass <sjg at chromium.org>
>>>> ---

[...]

>>> Just out of interest, is it possible to test this? How would I plumb it
>>> in?
>>
>> Well, from my experience with ULPI hardware,
>> I think the controller specific glue looks like the right place
>> for putting the ULPI layer calls in.
>>
>> In general, the controller code knows which PHYs it supports
>> and board code knows which PHY is assembled on the board,
>> so it is not that straight simple to find the right place.
>>
>> I think, Marek has patches that supposed to use this framework on efikamx
>> board.
> 
> I tried using the interface, but the design seems completely wrong :-( Jana was 
> supposed to design it mainly for the efikamx board, but this interface is 
> unusable there.

May I ask you why?
Isn't it because of that nasty VBUS bug efikamx has?
You can't say the design is wrong if it is more generic then you want...

> I had to fall back to basic ulpi_read()/ulpi_write() calls :-( 

That's too bad.
Because ulpi_{read|write}() is only a viewport implementation and
it is not following the ULPI spec.

> I'm afraid we won't make it for .12 release window with this patches ... very 
> bad :-( I'll try talking to WD if he can push the release window to allow this 

Good.

> (or redesigned version) in, but I don't know if that's a good idea.

I don't think it should be redesigned.
Currently, it is generic and abstracts the ULPI specification nicely.
It can be used on any architecture.
I have already stated in the cover letter,
what IMO is missing to improve usability, but that will not be a problem.

Do you have the efikamx patches somewhere I can look at?


-- 
Regards,
Igor.