Messages in this thread |  | | Subject | Re: [alsa-devel] [PATCH linux-next v2 9/9] ASoC: rsnd: add busif property to dai stream | From | Jiada Wang <> | Date | Thu, 4 Oct 2018 11:43:18 +0900 |
| |
Hi Morimoto-san
On 2018/10/04 10:41, Kuninori Morimoto wrote: > Hi Jiada > > Thank you for your patch > >> in GEN3 SSI may use different BUSIF for data transfer, >> this patch adds busif property to each dai stream, >> to indicate the BUSIF used by playback/capture stream. >> >> Also adds rsnd_ssi_select_busif() to automatically select >> BUSIF (currently only BUSIF0 is selected) >> >> Signed-off-by: Jiada Wang <jiada_wang@mentor.com> >> --- >> sound/soc/sh/rcar/core.c | 3 +++ >> sound/soc/sh/rcar/dma.c | 31 +++++++++++++++++++++++++++++++ >> sound/soc/sh/rcar/rsnd.h | 3 +++ >> sound/soc/sh/rcar/ssi.c | 30 +++++++++++++++++++++++++++++- >> 4 files changed, 66 insertions(+), 1 deletion(-) >> >> diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c >> index 40d7dc4f7839..5e3e6e65bcdf 100644 >> --- a/sound/soc/sh/rcar/core.c >> +++ b/sound/soc/sh/rcar/core.c >> @@ -1158,6 +1158,9 @@ static int rsnd_hw_params(struct snd_pcm_substream *substream, >> struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai); >> struct rsnd_dai_stream *io = rsnd_rdai_to_io(rdai, substream); >> int ret; >> + int chan = rsnd_runtime_channel_for_ssi_with_params(io, hw_params); >> + >> + rsnd_ssi_select_busif(io, chan); > If my understanding was correct, the chance to use BUSIFx is when TDM split mode. Yes, only when SSI works in Split/Ex-Split mode, BUSIFx other than 0 is necessary > And this patch selects it on runtime (= hw_param) ? Because, in order to automatically determine BUSIF number, information like SSI mode (non-Split/Split/Ex-Split), runtime channel, are required (in our internal implementation, SSI mode is selected by kctrl) because of this, in this patch, BUSIF is selected on runtime
> But, I think we can/should select it on probe timing from DT connection. > Am I misunderstanding ? with the above reasoning, BUSIF is selected on runtime. what do you think?
Thanks, Jiada > I'm not sure how to select, but adding new ssiuX0 - ssiuX7 > is realistic idea (parse sound card is not realistic...) ? > If so, your rxu/txu DMA can be more simple ?
|  |