From 2c0066767db8d76fb61f67d723f19f85533c249e Mon Sep 17 00:00:00 2001
From: Iliyan Malchev <malchev@google.com>
Date: Fri, 29 Mar 2013 11:08:39 -0700
Subject: [PATCH] ASoC: msm: Flexible period size for pcm playback

PCM driver was configured for fixed buffer
size on the playback path. With this, varying
the buffer sizes on the playback path was not
possible. To fix this, support for flexible
period sizes is added by setting different
values for min and max buffer sizes

Signed-off-by: Alexy Joseph <alexyj@codeaurora.org>
Signed-off-by: Mekala Natarajan <mekalan@codeaurora.org>
---
 sound/soc/msm/msm-pcm-q6.c | 45 +++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 22 deletions(-)

diff --git a/sound/soc/msm/msm-pcm-q6.c b/sound/soc/msm/msm-pcm-q6.c
index f4d7c65af49..8e8931fa1b7 100644
--- a/sound/soc/msm/msm-pcm-q6.c
+++ b/sound/soc/msm/msm-pcm-q6.c
@@ -39,11 +39,12 @@ struct snd_msm {
 	struct snd_pcm *pcm;
 };
 
-#define PLAYBACK_NUM_PERIODS	8
-#define PLAYBACK_PERIOD_SIZE	2048
-#define CAPTURE_NUM_PERIODS	2
-#define CAPTURE_MAX_PERIOD_SIZE 4096
-#define CAPTURE_MIN_PERIOD_SIZE 320
+#define PLAYBACK_NUM_PERIODS		8
+#define PLAYBACK_MAX_PERIOD_SIZE	4096
+#define PLAYBACK_MIN_PERIOD_SIZE	1024
+#define CAPTURE_NUM_PERIODS		2
+#define CAPTURE_MAX_PERIOD_SIZE		4096
+#define CAPTURE_MIN_PERIOD_SIZE		320
 
 static struct snd_pcm_hardware msm_pcm_hardware_capture = {
 	.info =                 (SNDRV_PCM_INFO_MMAP |
@@ -77,9 +78,9 @@ static struct snd_pcm_hardware msm_pcm_hardware_playback = {
 	.rate_max =             48000,
 	.channels_min =         1,
 	.channels_max =         2,
-	.buffer_bytes_max =     PLAYBACK_NUM_PERIODS * PLAYBACK_PERIOD_SIZE,
-	.period_bytes_min =	PLAYBACK_PERIOD_SIZE,
-	.period_bytes_max =     PLAYBACK_PERIOD_SIZE,
+	.buffer_bytes_max =     PLAYBACK_NUM_PERIODS * PLAYBACK_MAX_PERIOD_SIZE,
+	.period_bytes_min =	PLAYBACK_MIN_PERIOD_SIZE,
+	.period_bytes_max =     PLAYBACK_MAX_PERIOD_SIZE,
 	.periods_min =          PLAYBACK_NUM_PERIODS,
 	.periods_max =          PLAYBACK_NUM_PERIODS,
 	.fifo_size =            0,
@@ -362,6 +363,17 @@ static int msm_pcm_open(struct snd_pcm_substream *substream)
 		pr_err("snd_pcm_hw_constraint_integer failed\n");
 
 
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		ret = snd_pcm_hw_constraint_minmax(runtime,
+			SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
+			PLAYBACK_NUM_PERIODS * PLAYBACK_MIN_PERIOD_SIZE,
+			PLAYBACK_NUM_PERIODS * PLAYBACK_MAX_PERIOD_SIZE);
+		if (ret < 0) {
+			pr_err("constraint for buffer bytes min max ret = %d\n",
+									ret);
+		}
+	}
+
 	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
 		ret = snd_pcm_hw_constraint_minmax(runtime,
 			SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
@@ -668,18 +680,10 @@ static int msm_pcm_hw_params(struct snd_pcm_substream *substream,
 			prtd->session_id, substream->stream);
 		}
 
-	if (dir == OUT) {
-		ret = q6asm_audio_client_buf_alloc_contiguous(dir,
+	ret = q6asm_audio_client_buf_alloc_contiguous(dir,
 			prtd->audio_client,
 			(params_buffer_bytes(params) / params_periods(params)),
-				params_periods(params));
-	} else {
-		ret = q6asm_audio_client_buf_alloc_contiguous(dir,
-			prtd->audio_client,
-			runtime->hw.period_bytes_min,
-			runtime->hw.periods_max);
-	}
-
+			params_periods(params));
 	if (ret < 0) {
 		pr_err("Audio Start: Buffer Allocation failed \
 					rc = %d\n", ret);
@@ -696,10 +700,7 @@ static int msm_pcm_hw_params(struct snd_pcm_substream *substream,
 	dma_buf->area = buf[0].data;
 	dma_buf->addr =  buf[0].phys;
 	dma_buf->bytes = runtime->hw.buffer_bytes_max;
-	if (dir == IN)
-		dma_buf->bytes = runtime->hw.buffer_bytes_max;
-	else
-		dma_buf->bytes = params_buffer_bytes(params);
+	dma_buf->bytes = params_buffer_bytes(params);
 
 	if (!dma_buf->area)
 		return -ENOMEM;