Re: [PATCH v3.5] dw_dmac: return proper residue value

[Andy Shevchenko]

On Fri, Jan 25, 2013 at 11:30 AM, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
> On Fri, Jan 25, 2013 at 2:49 PM, Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> wrote:
>> On Fri, Jan 25, 2013 at 11:07 AM, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
>>> Who is going to right on ctlhi/lo?
>
> Ahh, my English :( (/s/right/write)
>
>> dwc_do_single_block()
>>
>>> we write to ctlhi/lo only when we program new
>>> transfer. and that is not going to happen while we are in middle of a transfer.
>>
>> We have got a tasklet running inside tx_status call. Isn't possible?
>> tasklet runs scan_descriptors, that continues transfer in soft LLP mode.
>
> But we have just executed scan_descriptor() before this function and it doesn't
> look possible that transfer wasn't over then and inbetween these calls we got an
> interrupt, scheduled an tasklet and called dwc_do_single_block() :)

Yeah, the keyword is "look". 1 per million cases it could be true. I
think this discussion is going to the dead end.
Anyone else would like to argue for one or the other opinion?

I might obey your way with the commentary that with quite lower
possibility we could have an issue there.

-- 
With Best Regards,
Andy Shevchenko
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