Subject: USB support on i.MX27

From: [email-masked] (Valentin Longchamp)
Date: Wed, 02 Dec 2009 09:43:03 +0100

Hi Daniel and Alan,

Alan Carvalho de Assis wrote:
> Hi Daniel,
> 
> On 12/1/09, Daniel Mack <[email-masked]> wrote:
>> Hmm, I don't follow. You added some debug output and it started working,
>> is that what you say? Do we possibly need memory barriers somewhere?
>>
> 
> Basically it, but I will do more tests to isolate the issue.
> 
> In fact there is a board where the issue remain, but using old kernel
> (2.6.22) both work.

I am also investigating this issue. The same happens sometimes with my 
USB host with ULPI-ISP1504, but it never happens with the USB slave with 
the exact same hardware ULPI-ISP1504, that's why I have the feeling that 
it's a purely software issue.

I also had the feeling that it was a timing issue (maybe with a clock 
not ready at the right time) and what I read from Alan comforts me with 
this feeling. But I haven't been able to isolate this either.

Best Regards

Val

-- 
Valentin Longchamp, PhD Student, EPFL-STI-LSRO1
valentin.longchamp at epfl.ch, Phone: +41216937827
http://people.epfl.ch/valentin.longchamp
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