On Tue, Apr 22, 2014 at 05:39:28PM -0700, Dmitry Torokhov wrote:

On Tue, Apr 22, 2014 at 10:18:21PM +0100, Mark Brown wrote:

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Remove the bitrotted comment, though in actual fact the use case mentioned is a great use for spi_async() since it would cut down on latency handling the interrupt by saving us a context switch before we start SPI.

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This was previously implemented, it was removed in commit b534422b2d11 (Input: ad7877 - switch to using threaded IRQ) for code complexity reasons. It may be better to revert that commit instead.

Hmm, maybe.. although I think original would cause device 'stuck' if call to spi_async() fails, so probably not a straight revert...

Probably best just to apply this, then - someone can always reimplement if they need to.