Messages in this thread | | | Subject | Re: [PATCH 5/7 v2] dma: sh: use an integer slave ID to improve API compatibility | From | Vinod Koul <> | Date | Mon, 16 Jul 2012 13:58:25 +0530 |
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On Mon, 2012-07-16 at 09:13 +0200, Guennadi Liakhovetski wrote: > > > They tell the driver how the channel has to be configured to > support this > > > specific client. They are values of two specific registers. In > fact, CHCR > > > means exactly that - CHannel Control Register. > > what exactly does the channel control register do in shdma? Should > shdma > > driver deduce this value rather than client giving it? > > Same question for mid_rid? > > See, e.g., > arch/arm/mach-shmobile/setup-sh7372.c::sh7372_dmae_slaves[]. > Platforms are supplying these values with shdma driver platform data, > together with slave IDs. Them when slaves request channels and supply > their slave IDs, the driver searches the above array, looking for the > matching slave ID, then it uses the rest of the information in those > structs to configure the channel for this client. Again, this is > nothing > new, this is how the driver has been functioning since a long time, > this > driver is not modifying anything there. Any changes to this > procedure, > like providing all thig information from clients themselves instead > of > keeping it with DMACs, requires these patches to be committed first. That wasn't my question.
I want to know what does ccr and mid_rid mean to dmac here?
-- ~Vinod
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