Re: [PATCH v5 08/10] spi: expose master transfer size limitation.

[Heiner Kallweit]

Am 01.12.2015 um 20:58 schrieb Mark Brown:
> 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?
> 
Sure .. Just one inquiry:
When you say "the naming here" you refer to Michal's or my version?

Actually I like in Michal's hook that it directly takes a struct spi_device.
This saves the caller one level of indirection as the caller usually will
deal with a spi_device and not a spi_master.

If you're fine with Michal's version then this is also fine with me,
especially as the functionality is the same.

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