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

From	Mark Brown <broonie@kernel.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH v5 08/10] spi: expose master transfer size limitation.
Date	2015-12-07 21:20 +0100
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On Fri, Dec 04, 2015 at 03:30:50PM +0100, Martin Sperl wrote:
> > On 02.12.2015, at 00:12, Mark Brown <broonie@kernel.org> wrote:

> > Can we change this to return SIZE_MAX instead (ie, the maximum value for
> > a size_t)?  That way callers don't need to worry if there is a limit, if
> > they want to handle it they can just unconditionally assume that a limit
> > will be provided.

> As I just came across: spi_master.max_dma_len, so I wonder how this 
> value would differ from the proposed spi_master.max_transfer_size
> on specific HW?

> For all practical purposes I would assume both are identical.

Yeah, we should probably just remove the DMA specific one in time though
it may be useful for some devices with built in DMA engines if they're
oddly limited I'm not sure how practical their DMA would be if it
differed from the overall transfer length.

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Re: [PATCH v5 08/10] spi: expose master transfer size limitation. Mark Brown <broonie@kernel.org> - 2015-12-02 00:20 +0100
  Re: [PATCH v5 08/10] spi: expose master transfer size limitation. Michal Suchanek <hramrach@gmail.com> - 2015-12-02 10:40 +0100
  Re: [PATCH v5 08/10] spi: expose master transfer size limitation. Martin Sperl <martin@sperl.org> - 2015-12-04 15:40 +0100
    Re: [PATCH v5 08/10] spi: expose master transfer size limitation. Michal Suchanek <hramrach@gmail.com> - 2015-12-04 17:50 +0100
    Re: [PATCH v5 08/10] spi: expose master transfer size limitation. Mark Brown <broonie@kernel.org> - 2015-12-07 21:20 +0100

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