ASoC: rsnd: make sure SSI parent/child uses same number of sound channel.

SSI parent/child need to use same number of sound data channel
if these are sharing clock/ws pin. this patch makes it sure.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index 2ef48a44c4ab..5b89723c3206 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -66,6 +66,7 @@ struct rsnd_ssi {
 
         u32 cr_own;
         u32 cr_clk;
+        int chan;
         int err;
         unsigned int usrcnt;
 };
@@ -264,6 +265,8 @@ static void rsnd_ssi_hw_stop(struct rsnd_ssi *ssi)
                 }
 
                 rsnd_mod_hw_stop(&ssi->mod);
+
+                ssi->chan = 0;
         }
 
         dev_dbg(dev, "%s[%d] hw stopped\n",
@@ -340,6 +343,35 @@ static int rsnd_ssi_quit(struct rsnd_mod *mod,
         return 0;
 }
 
+static int rsnd_ssi_hw_params(struct rsnd_mod *mod,
+                              struct snd_pcm_substream *substream,
+                              struct snd_pcm_hw_params *params)
+{
+        struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
+        struct rsnd_ssi *ssi_parent = rsnd_ssi_parent(ssi);
+        int chan = params_channels(params);
+
+        /*
+         * Already working.
+         * It will happen if SSI has parent/child connection.
+         */
+        if (ssi->usrcnt) {
+                /*
+                 * it is error if child <-> parent SSI uses
+                 * different channels.
+                 */
+                if (ssi->chan != chan)
+                        return -EIO;
+        }
+
+        /* It will be removed on rsnd_ssi_hw_stop */
+        ssi->chan = chan;
+        if (ssi_parent)
+                return rsnd_ssi_hw_params(&ssi_parent->mod, substream, params);
+
+        return 0;
+}
+
 static void rsnd_ssi_record_error(struct rsnd_ssi *ssi, u32 status)
 {
         /* under/over flow error */
@@ -460,6 +492,7 @@ static struct rsnd_mod_ops rsnd_ssi_pio_ops = {
         .quit   = rsnd_ssi_quit,
         .start  = rsnd_ssi_start,
         .stop   = rsnd_ssi_stop,
+        .hw_params = rsnd_ssi_hw_params,
 };
 
 static int rsnd_ssi_dma_probe(struct rsnd_mod *mod,
@@ -569,6 +602,7 @@ static struct rsnd_mod_ops rsnd_ssi_dma_ops = {
         .start  = rsnd_ssi_dma_start,
         .stop   = rsnd_ssi_dma_stop,
         .fallback = rsnd_ssi_fallback,
+        .hw_params = rsnd_ssi_hw_params,
 };
 
 int rsnd_ssi_is_dma_mode(struct rsnd_mod *mod)