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From: Michal Suchanek <hramrach@gmail.com>
Date: Wed, 2 Dec 2015 10:55:16 +0100
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Subject: Re: [PATCH v5 08/10] spi: expose master transfer size limitation.
To: Mark Brown <broonie@kernel.org>
Cc: Heiner Kallweit <hkallweit1@gmail.com>,
        David Woodhouse <dwmw2@infradead.org>,
        Brian Norris <computersforpeace@gmail.com>,
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On 1 December 2015 at 20:58, Mark Brown <broonie@kernel.org> wrote:
> On Tue, Dec 01, 2015 at 04:51:06PM -0000, Michal Suchanek wrote:
>> On some SPI controllers it is not feasible to transfer arbitrary amount
>> of data at once.
>>
>> When the limit on transfer size is a few kilobytes at least it makes
>> sense to use the SPI hardware rather than reverting to gpio driver.
>
>> +     /*
>> +      * on some hardware transfer size may be constrained
>> +      * the limit may depend on device transfer settings
>> +      */
>> +     size_t (*max_transfer_size)(struct spi_device *spi);
>
> Heiner submitted a *very* similar patch just now with a straight
> variable plus accessor instead of a function and using a name with _msg.
> I'm ambivalent on the implementation but prefer the naming here since
> that's more the limitation we're trying to express I think (some
> hardware does have limiations about multple transfers too).  Can the two
> of you come up with something that works for both of you?

Sorry, missed there is a patch because it shows in the middle of the
discussion for me.

I don't really care which one it is so long as I can get the last
patch in this series based on it.

Thanks

Michal