Re: [PATCH 0/2] OMAP2+: DMA: fix src/dst position reporting

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On 10/31/2011 04:20 PM, Peter Ujfalusi wrote:
Hello,

If the user asks for the sDMA current position before the first
data has been transmitted (before the first DMA request has been
generated), the reported position is not valid:
src position: CSAC is uninitialized
dst position: CDAC is 0

The return values in both case considered invalid.
This sitation can be identified by checking if the CDAC register
is 0 (it is initialized to 0 in omap_dam_start call).
In this case return the programmed source/destination address.

The affected omap_get_dma_src_pos/omap_get_dma_dst_pos functions
are used by the audio stack mainly for checking the current position
of the audio stream.

Regards,
Peter
---
Peter Ujfalusi (2):
   OMAP2+: DMA: Workaround for invalid source position
   OMAP2+: DMA: Workaround for invalid destination position

  arch/arm/plat-omap/dma.c |   25 ++++++++++++++++++++++---
  1 files changed, 22 insertions(+), 3 deletions(-)

Both,

Reviewed-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxx>
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