Porting 3.5 Kernel to a new ARM platform: DMA issues

Porting 3.5 Kernel to a new ARM platform: DMA issues

[alberto Villa]

Hello,

I'm working to port 3.5 Kernel to a new platform and I'm trying to be
compliant with the new features of newer Kernel versions (I'm familiar
with 2.6). To be more specific I'm trying to adapt the port to the DMA
engine: I've got the DMA driver and the peripheral's driver which use
the DMA engine.
On older Kernel version one could write for example a dma.c under
linux/arch/arm/mach-<arch> to provide dma's specific alloc/release
functions to take care for example of a MUX between peripherals and DMA.
In release 3.5 I found the function dma_filter called during the
dma_request_channel () that seems to provide the functionality I need to
set a MUX for example during the allocation of the DMA channel, but I
can't find any customizable function called during the
dma_release_channel() to change the configuration of the MUX I set
during the dma_request_channel().
Am I missing something or in new releases this kind of operation isn't
supported?

Thank you

-- 
Dr. Villa Alberto
Sw Engineer

SeleTech srl
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