[PATCH V2 4/4] DMA: PL330: Modify pl330 filter based on new generic dma dt bindings.

Padma Venkat padma.kvr at gmail.com
Mon Feb 4 00:21:29 EST 2013

On Sat, Feb 2, 2013 at 8:39 PM, Arnd Bergmann <arnd at arndb.de> wrote:
> On Saturday 02 February 2013 08:00:54 Padma Venkat wrote:
>> > The result of this looks good, but I fear that changing the filter function
>> > like this wil break all drivers that currently use the plat-samsung/dma-ops.c
>> > code. For migration purposes, I think the best way is to change
>> > samsung_dmadev_request() to match the new filter_param format.
>> >
>> > After that is done, you can migrate all the drivers using samsung_dma_get_ops
>> > over to the new dma_request_slave_channel interface without breaking
>> > anything when only part of the series is applied.
>> >
>> >         Arnd
>> Please check the below link where I made the dma request compatible to
>> both DT and non-DT
>> http://git.kernel.org/?p=linux/kernel/git/broonie/sound.git;a=commit;h=e7ba5f1d0f6292e1b99c63cc4bb74c70232e9065
>> http://git.kernel.org/?p=linux/kernel/git/broonie/sound.git;a=commit;h=b5be04d35dbb2e00ab27a97bfd26e17019e857ef
>> Please let me know if any changes required.
> Those two changes by themselves still look ok, I think but you
> still break the non-DT case in this 4/4 patch by changing the
> pl330_filter function in an incompatible way. You will still
> have to either change the filter_param argument in the
> samsung_dmadev_request() function, or provide separate filter
> functions, one to be used by samsung_dmadev_request and
> one for the pl330_xlate function.

I missed out to delete this part. Thanks for your point. I will send
another patch.

> In the long run, I think it would be better to move the slave
> drivers away from the samsung_dma wrappers and use
> dma_request_slave_channel directly, but that is an independent
> discussion.
>         Arnd


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