[alsa-devel] [PATCH 6/8] ASoC: rsnd: add nolock_start/stop callback

[Kuninori Morimoto]

From: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>

Current Renesas Sound driver requests DMA channel when .probe timing,
and release it when .remove timing. And use DMA on .start/.stop
But, Audio DMAC power ON was handled when request timing (= .probe),
and power OFF was when release timing (= .remove).
This means Audio DMAC power is always ON during driver was enabled.
To fixup this issue, it should request/release DMA channel on each
playback/recorde timing.
But, DMA channel request/release function uses mutex lock inside.
This means it will breaks current spinlock's interrupt protect.
To solve this issue, DMA channel request/release function needs to
be called from non-spinlock area. This patch adds its callback.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
---
 sound/soc/sh/rcar/core.c | 26 ++++++++++++++++++++++++++
 sound/soc/sh/rcar/rsnd.h | 15 ++++++++++++++-
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index ea14a14..9ffa299 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -716,7 +716,33 @@ static int rsnd_soc_set_dai_tdm_slot(struct snd_soc_dai *dai,
 	return 0;
 }
 
+static int rsnd_soc_dai_startup(struct snd_pcm_substream *substream,
+				struct snd_soc_dai *dai)
+{
+	struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai);
+	struct rsnd_dai_stream *io = rsnd_rdai_to_io(rdai, substream);
+
+	/*
+	 * call rsnd_dai_call without spinlock
+	 */
+	return rsnd_dai_call(nolock_start, io, priv);
+}
+
+static void rsnd_soc_dai_shutdown(struct snd_pcm_substream *substream,
+				  struct snd_soc_dai *dai)
+{
+	struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai);
+	struct rsnd_dai_stream *io = rsnd_rdai_to_io(rdai, substream);
+
+	/*
+	 * call rsnd_dai_call without spinlock
+	 */
+	rsnd_dai_call(nolock_stop, io, priv);
+}
+
 static const struct snd_soc_dai_ops rsnd_soc_dai_ops = {
+	.startup	= rsnd_soc_dai_startup,
+	.shutdown	= rsnd_soc_dai_shutdown,
 	.trigger	= rsnd_soc_dai_trigger,
 	.set_fmt	= rsnd_soc_dai_set_fmt,
 	.set_tdm_slot	= rsnd_soc_set_dai_tdm_slot,
diff --git a/sound/soc/sh/rcar/rsnd.h b/sound/soc/sh/rcar/rsnd.h
index c1cee1a..422b534 100644
--- a/sound/soc/sh/rcar/rsnd.h
+++ b/sound/soc/sh/rcar/rsnd.h
@@ -259,6 +259,12 @@ struct rsnd_mod_ops {
 	int (*fallback)(struct rsnd_mod *mod,
 			struct rsnd_dai_stream *io,
 			struct rsnd_priv *priv);
+	int (*nolock_start)(struct rsnd_mod *mod,
+		    struct rsnd_dai_stream *io,
+		    struct rsnd_priv *priv);
+	int (*nolock_stop)(struct rsnd_mod *mod,
+		    struct rsnd_dai_stream *io,
+		    struct rsnd_priv *priv);
 };
 
 struct rsnd_dai_stream;
@@ -276,8 +282,9 @@ struct rsnd_mod {
 /*
  * status
  *
- * 0xH0000CB0
+ * 0xH0000CBA
  *
+ * A	0: nolock_start	1: nolock_stop
  * B	0: init		1: quit
  * C	0: start	1: stop
  *
@@ -287,6 +294,8 @@ struct rsnd_mod {
  * H	0: fallback
  * H	0: hw_params
  */
+#define __rsnd_mod_shift_nolock_start	0
+#define __rsnd_mod_shift_nolock_stop	0
 #define __rsnd_mod_shift_init		4
 #define __rsnd_mod_shift_quit		4
 #define __rsnd_mod_shift_start		8
@@ -300,6 +309,8 @@ struct rsnd_mod {
 
 #define __rsnd_mod_add_probe		0
 #define __rsnd_mod_add_remove		0
+#define __rsnd_mod_add_nolock_start	 1
+#define __rsnd_mod_add_nolock_stop	-1
 #define __rsnd_mod_add_init		 1
 #define __rsnd_mod_add_quit		-1
 #define __rsnd_mod_add_start		 1
@@ -319,6 +330,8 @@ struct rsnd_mod {
 #define __rsnd_mod_call_pcm_new		0
 #define __rsnd_mod_call_fallback	0
 #define __rsnd_mod_call_hw_params	0
+#define __rsnd_mod_call_nolock_start	0
+#define __rsnd_mod_call_nolock_stop	1
 
 #define rsnd_mod_to_priv(mod) ((mod)->priv)
 #define rsnd_mod_id(mod) ((mod) ? (mod)->id : -1)
-- 
1.9.1