[alsa-devel] [PATCH 0/3] ASoC: Davinci: McASP: add support new McASP IP Variant

Daniel Mack zonque at gmail.com
Wed Oct 3 10:07:41 EDT 2012

On 03.10.2012 14:57, Hebbar, Gururaja wrote:
> On Wed, Oct 03, 2012 at 16:46:39, Daniel Mack wrote:
>> On 03.10.2012 09:16, Hebbar, Gururaja wrote:
>>> On Wed, Oct 03, 2012 at 03:58:45, Daniel Mack wrote:
>>>> On 31.08.2012 14:50, Hebbar, Gururaja wrote:
>>>>> The OMAP2+ variant of McASP is different from Davinci variant w.r.to some
>>>>> register offset and missing generic SRAM APIs support
>>>>> Changes
>>>>> - Add new MCASP_VERSION_3 to identify new variant. New DT compatible
>>>>>   "ti,omap2-mcasp-audio" to identify version 3 controller.
>>>>> - The register offsets are handled depending on the version.
>>>>> - Provide a config option to indicate missing SRAM API support.
>>>> Could you give some insight which hardware this was tested on? I'm
>>>> trying to get this up and running on a AM33xx board, and the patches
>>>> look all reasonable to me. My problem is that I can't make the DMA
>>>> engine move forward, I fail to receive a single interrupt on this
>>>> peripheral after the stream starts. I will continue searching for the
>>>> reason of this tomorrow, but maybe you can give me some hint by
>>>> explaining your setup?
>>>> Note that I'm using your patches together with Matt's from this series:
>>>>   https://github.com/ohporter/linux/tree/edma-dmaengine-am33xx-rfc-v1
>>>> ... but it doesn't work without those either.
>>> When I started working on adding DT support to McASP driver, Matt Porter 
>>> EDMA port was not yet ready. 
>>> So 
>>> 1. I took existing edma driver from AM335x Arago release [1] (driver + edma 
>>>    device init). 
>>> 2. Added this to Vaibhav's Local (linux-next + AM335x patches) tree [2] 
>>> 3. Added DT support to McASP driver.
>>> I tested this on AM335x EVM board. 
>> Hmm, so I think there's a tiny bit missing for the EDMA conversion on DT
>> kernels.
>>> If you need the code, I can share it as a patch (I will send the patch as a 
>>> private mail since the patch is huge).
>> Please do :) Or just push your entire tree somewhere.
> I have pushed the code at below git repo
> Repo :https://github.com/hvaibhav/am335x-linux
> Branch : am335x-upstream-staging-audio
> This includes 
> 1. (linux-next + AM335x patches)
> 2. McASP DT conversion
> 3. EDMA hack
> 4. AM335x audio specific DT blobs
> 5. Am335x dma DT blobs [hack]

Ha, that 5th point was what I was missing, in particular these DMA
offset matching bits. Thanks a lot! I'll get back to you soon with some
patches for the mcasp driver.


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