On Fri, 10 Nov 2017 08:02:01 +0000 Radu Andrei Alexe <radu.alexe@xxxxxxx> wrote: > On 11/9/2017 6:34 PM, Kim Phillips wrote: > > On Thu, 9 Nov 2017 11:54:13 +0000 > > Radu Andrei Alexe <radu.alexe@xxxxxxx> wrote: > >> The next patch version will create the platform device dynamically at > >> run time. > > > > Why create a new device when that h/w already has one? > > > > Why doesn't the existing crypto driver register dma capabilities with > > the dma driver subsystem? > > > I can think of two reasons: > > 1. The code that this driver introduces has nothing to do with crypto > and everything to do with dma. I would think that at least a crypto "null" algorithm implementation would share code. > Placing the code in the same directory as > the caam subsystem would only create confusion for the reader of an > already complex driver. this different directory argument seems to be identical to your 2 below: > 2. I wanted this driver to be tracked by the dma engine team. They have > the right expertise to provide adequate feedback. If all the code was in > the crypto directory they wouldn't know about this driver or any > subsequent changes to it. dma subsystem bits could still be put in the dma area if deemed necessary but I don't think it is: I see drivers/crypto/ccp/ccp-dmaengine.c calls dma_async_device_register for example. I also don't see how that complicates things much further. What is the rationale for using the crypto h/w as a dma engine anyway? Are there supporting performance figures? Kim
