Re: [PATCH linux-next 01/10] ASoC: rsnd: ssi: Request dedicated dma channels for busif1 to 7

From: Kuninori Morimoto
Date: Thu Sep 27 2018 - 20:08:21 EST



Hi Jiada
Cc: linux-renesas-soc ML

Thank you for your patch

> From: Jiada Wang <jiada_wang@xxxxxxxxxx>
>
> Currently ssi driver only request dma channel for SSI_0,
> which is used to transfer data to/from busif0.
>
> But since busif1 to busif7 also maybe used, dedicated dma channels
> are request for data transfer between these busif.
>
> Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
> ---
(snip)
> @@ -938,12 +940,20 @@ static struct dma_chan *rsnd_ssi_dma_req(struct rsnd_dai_stream *io,
> {
> struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
> int is_play = rsnd_io_is_play(io);
> - char *name;
> + int busif = rsnd_ssi_get_busif(io);
> + char name[SSI_DMA_NAME_SIZE];
>
> - if (rsnd_ssi_use_busif(io))
> - name = is_play ? "rxu" : "txu";
> - else
> - name = is_play ? "rx" : "tx";
> + if (rsnd_ssi_use_busif(io)) {
> + if (is_play)
> + snprintf(name, SSI_DMA_NAME_SIZE, "rxu%d", busif);
> + else
> + snprintf(name, SSI_DMA_NAME_SIZE, "txu%d", busif);
> + } else {
> + if (is_play)
> + snprintf(name, SSI_DMA_NAME_SIZE, "rx");
> + else
> + snprintf(name, SSI_DMA_NAME_SIZE, "tx");
> + }

Unfortunately, this patch breaks "git bisect", and Gen2 platforms.
We need to keep existing "rxu/txu" more. Please consider compatibility.
# we can remove it 2 or 3 version later ?

If the commit which has this patch, but doesn't have [02/xx] or later,
it can't use BUSIF.

And your patch doesn't care Gen2 series.
DT compatibility is very sensitive...