Hi Jarkko,
On Wed, Aug 05, 2009 at 09:48:56AM +0200, ext Jarkko Nikula wrote:
> On Thu, 30 Jul 2009 15:49:39 +0300
> Eduardo Valentin <eduardo.valentin@xxxxxxxxx> wrote:
>
> > Now this patch implements again the McBSP threshold
> > usage for OMAP ASoC.
> >
> > We figured out that there is no need to have so much
> > SW control in order to have DMA in idle state during
> > audio streaming. Configuring McBSP threshold value
> > and DMA to FRAME_SYNC are sufficient.
> >
> > Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxxxxx>
> > ---
> > sound/soc/omap/omap-pcm.c | 37 +++++++++++++++++++++++++++++++++++--
> > 1 files changed, 35 insertions(+), 2 deletions(-)
> >
> > @@ -192,6 +203,12 @@ static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
> > case SNDRV_PCM_TRIGGER_RESUME:
> > case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
> > prtd->period_index = 0;
> > + /* Configure McBSP internal buffer usage */
> > + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
> > + omap_mcbsp_set_tx_threshold(bus_id, samples - 1);
> > + else
> > + omap_mcbsp_set_rx_threshold(bus_id, samples - 1);
> > +
> > omap_start_dma(prtd->dma_ch);
> > break;
> >
> Oops, didn't notice this before. This will hard glue the DMA and McBSP
> together. Even currently there is only McBSP based DAI link driver,
> there can be others as well. EAC DAI for OMAP2420 would be necessary
> for instance if one wants to develop ASoC support for Nokia N800. Nokia
> N810 could use that too.
True. And the same comment is valid for the patch which adds op mode selection.
My idea to un-glue them is to put some callbacks in omap_mcbsp_data of omap-mcbsp.c,
and share it as something more generic, so that they can be called from omap-pcm.c.
Something like:
struct omap_dma_data {
unsigned int bus_id;
unsigned int fmt;
/*
* Flags indicating is the bus already activated and configured by
* another substream
*/
int active;
int configured;
/* threshold callbacks can be added then here */
void *data; /* struct omap_mcbsp_reg_cfg regs; can go here */
};
And this goes in omap-pcm.h.
what do you think??
>
>
> --
> Jarkko
--
Eduardo Valentin
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
