[alsa-devel] [PATCH 3/4] ALSA: CA0132: Add latency monitoring

[Ian Minett]

From: Ian Minett <ian_minett at creativelabs.com>

Add latency monitoring for playback, capture and DSP effects.

Signed-off-by: Ian Minett <ian_minett at creativelabs.com>

diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
index b52f00c..c797f65 100644
--- a/sound/pci/hda/patch_ca0132.c
+++ b/sound/pci/hda/patch_ca0132.c
@@ -133,6 +133,12 @@ enum {
 /* Effects values size*/
 #define EFFECT_VALS_MAX_COUNT 12
 
+#define DSP_CAPTURE_INIT_LATENCY        0
+#define DSP_CRYSTAL_VOICE_LATENCY       124
+#define DSP_PLAYBACK_INIT_LATENCY       13
+#define DSP_PLAY_ENHANCEMENT_LATENCY    30
+#define DSP_SPEAKER_OUT_LATENCY         7
+
 struct ct_effect {
 	char name[44];
 	hda_nid_t nid;
@@ -2761,8 +2767,27 @@ static void ca0132_cleanup_stream(struct hda_codec *codec, hda_nid_t nid)
 }
 
 /*
- * PCM callbacks
+ * PCM playbacks
  */
+static unsigned int ca0132_get_playback_latency(struct hda_codec *codec)
+{
+	struct ca0132_spec *spec = codec->spec;
+	unsigned int latency = DSP_PLAYBACK_INIT_LATENCY;
+
+	if (!dspload_is_loaded(codec))
+		return 0;
+
+	if (spec->effects_switch[PLAY_ENHANCEMENT - EFFECT_START_NID]) {
+		if ((spec->effects_switch[SURROUND - EFFECT_START_NID]) ||
+		    (spec->effects_switch[DIALOG_PLUS - EFFECT_START_NID]))
+			latency += DSP_PLAY_ENHANCEMENT_LATENCY;
+	}
+
+	if (spec->cur_out_type == SPEAKER_OUT)
+		latency += DSP_SPEAKER_OUT_LATENCY;
+	return latency;
+}
+
 static int ca0132_playback_pcm_prepare(struct hda_pcm_stream *hinfo,
 			struct hda_codec *codec,
 			unsigned int stream_tag,
@@ -2770,6 +2795,16 @@ static int ca0132_playback_pcm_prepare(struct hda_pcm_stream *hinfo,
 			struct snd_pcm_substream *substream)
 {
 	struct ca0132_spec *spec = codec->spec;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	unsigned int latency = ca0132_get_playback_latency(codec);
+
+	if (spec->dsp_state == DSP_DOWNLOADING) {
+		spec->dsp_stream_id = stream_tag;
+		return 0;
+	}
+
+	runtime->delay = bytes_to_frames(runtime, (latency * runtime->rate *
+					runtime->byte_align) / 1000);
 
 	ca0132_setup_stream(codec, spec->dacs[0], stream_tag, 0, format);
 
@@ -2834,8 +2869,22 @@ static int ca0132_dig_playback_pcm_close(struct hda_pcm_stream *hinfo,
 }
 
 /*
- * Analog capture
+ * PCM capture
  */
+
+static unsigned int ca0132_get_capture_latency(struct hda_codec *codec)
+{
+	struct ca0132_spec *spec = codec->spec;
+	unsigned int latency = DSP_CAPTURE_INIT_LATENCY;
+
+	if (!dspload_is_loaded(codec))
+		return 0;
+
+	if (spec->effects_switch[CRYSTAL_VOICE - EFFECT_START_NID])
+		latency += DSP_CRYSTAL_VOICE_LATENCY;
+	return latency;
+}
+
 static int ca0132_capture_pcm_prepare(struct hda_pcm_stream *hinfo,
 					struct hda_codec *codec,
 					unsigned int stream_tag,
@@ -2843,9 +2892,16 @@ static int ca0132_capture_pcm_prepare(struct hda_pcm_stream *hinfo,
 					struct snd_pcm_substream *substream)
 {
 	struct ca0132_spec *spec = codec->spec;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	unsigned int latency = ca0132_get_capture_latency(codec);
 
-	ca0132_setup_stream(codec, spec->adcs[substream->number],
-			    stream_tag, 0, format);
+	if (spec->dsp_state == DSP_DOWNLOADING)
+		return 0;
+
+	runtime->delay = bytes_to_frames(runtime, (latency * runtime->rate *
+					runtime->byte_align) / 1000);
+
+	ca0132_setup_stream(codec, hinfo->nid, stream_tag, 0, format);
 
 	return 0;
 }
@@ -3429,6 +3485,33 @@ static int ca0132_voicefx_set(struct hda_codec *codec, int enable)
 	return 1;
 }
 
+static void ca0132_update_latency(struct hda_codec *codec,
+				  unsigned int direction)
+{
+	struct ca0132_spec *spec = codec->spec;
+	unsigned int latency;
+	struct snd_pcm_substream *substr;
+	struct snd_pcm_runtime *runtime;
+
+	if (spec->dsp_state == DSP_DOWNLOADING)
+		return;
+
+	latency = (direction == SNDRV_PCM_STREAM_PLAYBACK)
+			? ca0132_get_playback_latency(codec)
+			: ca0132_get_capture_latency(codec);
+
+	substr = codec->pcm_info->pcm->streams[direction].substream;
+	while (substr) {
+		runtime = substr->runtime;
+		/* update latency only when frame_bits is set */
+		if (runtime && runtime->frame_bits)
+			runtime->delay = bytes_to_frames(runtime,
+					(latency * runtime->rate *
+					runtime->byte_align) / 1000);
+		substr = substr->next;
+	}
+}
+
 /*
  * Set the effects parameters
  */
@@ -3468,6 +3551,9 @@ static int ca0132_effects_set(struct hda_codec *codec, hda_nid_t nid, long val)
 	err = dspio_set_uint_param(codec, ca0132_effects[idx].mid,
 				   ca0132_effects[idx].reqs[0], on);
 
+	ca0132_update_latency(codec, SNDRV_PCM_STREAM_PLAYBACK);
+	ca0132_update_latency(codec, SNDRV_PCM_STREAM_CAPTURE);
+
 	if (err < 0)
 		return 0; /* no changed */
 
-- 
1.7.4.1