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Date: Thu, 28 Nov 2013 16:38:27 +0530
From: Sourav Poddar <sourav.poddar@ti.com>
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To: Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH 12/17] spi/qspi: convert driver to enable/disable memory
 mapped.
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On Thursday 28 November 2013 04:19 PM, Mark Brown wrote:
> On Thu, Nov 28, 2013 at 10:54:12AM +0530, Sourav Poddar wrote:
>
>> At the beginning of this api, I am doing a "disable memory mapped",
>> as becuase of
>> the code implemntation, if the control has reaches this api, memory
>> mapped is not
>> the desired operation. Then, at the end of this api after
>> "spi_finalize_current_message(master)", which indicated the current
>> transfer complete, I
>> issue a end of transfer command. Only after which, I enable memory
>> mapped mode again.
>> So, will the condition you mention above will hit.? Please help me
>> understand if i am
>> missing something?
> Removing the mapping isn't going to stop another context which has
> obtained a handle on the map trying to look at the mapping.
hmm..so the  'memcpy' part should be made atomic.(if possible?).