ASoC: DaVinci: McASP FIFO related updates

The DMA params for McASP with FIFO has been updated so that it works for
various FIFO levels. A member- 'fifo_level' has been added to the DMA
params data structure. The fifo_level can be adjusted by the tx[rx]_numevt
platform data. This is relevant only for DA8xx/OMAP-L1xx platforms. This
implementation has been tested for numevt values 1, 2, 4, 8.

Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

4 files changed, 28 insertions, 13 deletions

diff --git a/sound/soc/davinci/davinci-i2s.c b/sound/soc/davinci/davinci-i2s.c
index 4ae707048021..2ab809359c08 100644
--- a/sound/soc/davinci/davinci-i2s.c
+++ b/sound/soc/davinci/davinci-i2s.c
@@ -397,6 +397,8 @@ static int davinci_i2s_hw_params(struct snd_pcm_substream *substream,
         }
 
         dma_params->acnt  = dma_params->data_type;
+        dma_params->fifo_level = 0;
+
         rcr |= DAVINCI_MCBSP_RCR_RFRLEN1(1);
         xcr |= DAVINCI_MCBSP_XCR_XFRLEN1(1);
 
diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 5d1f98a4c978..50ad0519a8fa 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -714,16 +714,13 @@ static int davinci_mcasp_hw_params(struct snd_pcm_substream *substream,
         struct davinci_pcm_dma_params *dma_params =
                                         &dev->dma_params[substream->stream];
         int word_length;
-        u8 numevt;
+        u8 fifo_level;
 
         davinci_hw_common_param(dev, substream->stream);
         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-                numevt = dev->txnumevt;
+                fifo_level = dev->txnumevt;
         else
-                numevt = dev->rxnumevt;
-
-        if (!numevt)
-                numevt = 1;
+                fifo_level = dev->rxnumevt;
 
         if (dev->op_mode == DAVINCI_MCASP_DIT_MODE)
                 davinci_hw_dit_param(dev);
@@ -751,12 +748,12 @@ static int davinci_mcasp_hw_params(struct snd_pcm_substream *substream,
                 return -EINVAL;
         }
 
-        if (dev->version == MCASP_VERSION_2) {
-                dma_params->data_type *= numevt;
-                dma_params->acnt = 4 * numevt;
-        } else
+        if (dev->version == MCASP_VERSION_2 && !fifo_level)
+                dma_params->acnt = 4;
+        else
                 dma_params->acnt = dma_params->data_type;
 
+        dma_params->fifo_level = fifo_level;
         davinci_config_channel_size(dev, word_length);
 
         return 0;
diff --git a/sound/soc/davinci/davinci-pcm.c b/sound/soc/davinci/davinci-pcm.c
index 359e99ec7244..1152d8ba8970 100644
--- a/sound/soc/davinci/davinci-pcm.c
+++ b/sound/soc/davinci/davinci-pcm.c
@@ -66,38 +66,53 @@ static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream)
         dma_addr_t dma_pos;
         dma_addr_t src, dst;
         unsigned short src_bidx, dst_bidx;
+        unsigned short src_cidx, dst_cidx;
         unsigned int data_type;
         unsigned short acnt;
         unsigned int count;
+        unsigned int fifo_level;
 
         period_size = snd_pcm_lib_period_bytes(substream);
         dma_offset = prtd->period * period_size;
         dma_pos = runtime->dma_addr + dma_offset;
+        fifo_level = prtd->params->fifo_level;
 
         pr_debug("davinci_pcm: audio_set_dma_params_play channel = %d "
                 "dma_ptr = %x period_size=%x\n", lch, dma_pos, period_size);
 
         data_type = prtd->params->data_type;
         count = period_size / data_type;
+        if (fifo_level)
+                count /= fifo_level;
 
         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
                 src = dma_pos;
                 dst = prtd->params->dma_addr;
                 src_bidx = data_type;
                 dst_bidx = 0;
+                src_cidx = data_type * fifo_level;
+                dst_cidx = 0;
         } else {
                 src = prtd->params->dma_addr;
                 dst = dma_pos;
                 src_bidx = 0;
                 dst_bidx = data_type;
+                src_cidx = 0;
+                dst_cidx = data_type * fifo_level;
         }
 
         acnt = prtd->params->acnt;
         edma_set_src(lch, src, INCR, W8BIT);
         edma_set_dest(lch, dst, INCR, W8BIT);
-        edma_set_src_index(lch, src_bidx, 0);
-        edma_set_dest_index(lch, dst_bidx, 0);
-        edma_set_transfer_params(lch, acnt, count, 1, 0, ASYNC);
+
+        edma_set_src_index(lch, src_bidx, src_cidx);
+        edma_set_dest_index(lch, dst_bidx, dst_cidx);
+
+        if (!fifo_level)
+                edma_set_transfer_params(lch, acnt, count, 1, 0, ASYNC);
+        else
+                edma_set_transfer_params(lch, acnt, fifo_level, count,
+                                                        fifo_level, ABSYNC);
 
         prtd->period++;
         if (unlikely(prtd->period >= runtime->periods))
diff --git a/sound/soc/davinci/davinci-pcm.h b/sound/soc/davinci/davinci-pcm.h
index 8746606efc89..c8b0d2baf05a 100644
--- a/sound/soc/davinci/davinci-pcm.h
+++ b/sound/soc/davinci/davinci-pcm.h
@@ -23,6 +23,7 @@ struct davinci_pcm_dma_params {
         enum dma_event_q eventq_no;     /* event queue number */
         unsigned char data_type;        /* xfer data type */
         unsigned char convert_mono_stereo;
+        unsigned int fifo_level;
 };