[alsa-devel] i.MX audio support

[Sascha Hauer]

Hi Javier,

On Fri, Nov 20, 2009 at 08:51:31AM +0100, javier Martin wrote:
> Theoretically, current merged code only supports i.MX21/27 in the DMA
> part. So it would be correct adding a DMA separate driver for i.MX31.
> 
> However I disagree with completely new SSI code. It should be possible
> to add an arch define to export proper DMA structures whether we are
> using i.MX21/27 or i.MX31 in the current SSI driver.

I would agree if the current code worked and would be good shape.
Unfortunately it's not. It hardcodes the fact that there are 2 SSI units
(i.MX51 has three of them). Instead of writel/readl it uses direct pointer
derefs. The driver skips audio while it reinitialises the DMA engine. In
mx1_mx2_pcm_open() there are several memory leaks. The driver does not
call clk_get itself but depends on the board doing it. The only
available board support depends on a board not present in the kernel, so
we are not able to compile it (and it won't because the audmux
definitions are missing)

This all leads to a huge series of patches and much work and in the end
we would have a nearly rewritten driver.

Sascha

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