1 files changed, 56 insertions, 6 deletions

diff --git a/sound/soc/omap/omap-mcbsp.c b/sound/soc/omap/omap-mcbsp.c
index 4ac8a08db7b5..9fd00b091814 100644
--- a/sound/soc/omap/omap-mcbsp.c
+++ b/sound/soc/omap/omap-mcbsp.c
@@ -155,13 +155,23 @@ static void omap_mcbsp_set_threshold(struct snd_pcm_substream *substream)
         struct snd_soc_pcm_runtime *rtd = substream->private_data;
         struct snd_soc_dai *cpu_dai = rtd->dai->cpu_dai;
         struct omap_mcbsp_data *mcbsp_data = to_mcbsp(cpu_dai->private_data);
+        struct omap_pcm_dma_data *dma_data;
         int dma_op_mode = omap_mcbsp_get_dma_op_mode(mcbsp_data->bus_id);
         int words;
 
+        dma_data = snd_soc_dai_get_dma_data(rtd->dai->cpu_dai, substream);
+
         /* TODO: Currently, MODE_ELEMENT == MODE_FRAME */
         if (dma_op_mode == MCBSP_DMA_MODE_THRESHOLD)
-                /* The FIFO size depends on the McBSP word configuration */
-                words = snd_pcm_lib_period_bytes(substream) /
+                /*
+                 * Configure McBSP threshold based on either:
+                 * packet_size, when the sDMA is in packet mode, or
+                 * based on the period size.
+                 */
+                if (dma_data->packet_size)
+                        words = dma_data->packet_size;
+                else
+                        words = snd_pcm_lib_period_bytes(substream) /
                                                         (mcbsp_data->wlen / 8);
         else
                 words = 1;
@@ -351,6 +361,7 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
         struct omap_pcm_dma_data *dma_data;
         int dma, bus_id = mcbsp_data->bus_id;
         int wlen, channels, wpf, sync_mode = OMAP_DMA_SYNC_ELEMENT;
+        int pkt_size = 0;
         unsigned long port;
         unsigned int format, div, framesize, master;
 
@@ -373,9 +384,11 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
         switch (params_format(params)) {
         case SNDRV_PCM_FORMAT_S16_LE:
                 dma_data->data_type = OMAP_DMA_DATA_TYPE_S16;
+                wlen = 16;
                 break;
         case SNDRV_PCM_FORMAT_S32_LE:
                 dma_data->data_type = OMAP_DMA_DATA_TYPE_S32;
+                wlen = 32;
                 break;
         default:
                 return -EINVAL;
@@ -384,14 +397,53 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
                 dma_data->set_threshold = omap_mcbsp_set_threshold;
                 /* TODO: Currently, MODE_ELEMENT == MODE_FRAME */
                 if (omap_mcbsp_get_dma_op_mode(bus_id) ==
-                                                MCBSP_DMA_MODE_THRESHOLD)
-                        sync_mode = OMAP_DMA_SYNC_FRAME;
+                                                MCBSP_DMA_MODE_THRESHOLD) {
+                        int period_words, max_thrsh;
+
+                        period_words = params_period_bytes(params) / (wlen / 8);
+                        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                                max_thrsh = omap_mcbsp_get_max_tx_threshold(
+                                                            mcbsp_data->bus_id);
+                        else
+                                max_thrsh = omap_mcbsp_get_max_rx_threshold(
+                                                            mcbsp_data->bus_id);
+                        /*
+                         * If the period contains less or equal number of words,
+                         * we are using the original threshold mode setup:
+                         * McBSP threshold = sDMA frame size = period_size
+                         * Otherwise we switch to sDMA packet mode:
+                         * McBSP threshold = sDMA packet size
+                         * sDMA frame size = period size
+                         */
+                        if (period_words > max_thrsh) {
+                                int divider = 0;
+
+                                /*
+                                 * Look for the biggest threshold value, which
+                                 * divides the period size evenly.
+                                 */
+                                divider = period_words / max_thrsh;
+                                if (period_words % max_thrsh)
+                                        divider++;
+                                while (period_words % divider &&
+                                        divider < period_words)
+                                        divider++;
+                                if (divider == period_words)
+                                        return -EINVAL;
+
+                                pkt_size = period_words / divider;
+                                sync_mode = OMAP_DMA_SYNC_PACKET;
+                        } else {
+                                sync_mode = OMAP_DMA_SYNC_FRAME;
+                        }
+                }
         }
 
         dma_data->name = substream->stream ? "Audio Capture" : "Audio Playback";
         dma_data->dma_req = dma;
         dma_data->port_addr = port;
         dma_data->sync_mode = sync_mode;
+        dma_data->packet_size = pkt_size;
 
         snd_soc_dai_set_dma_data(cpu_dai, substream, dma_data);
 
@@ -419,7 +471,6 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
         switch (params_format(params)) {
         case SNDRV_PCM_FORMAT_S16_LE:
                 /* Set word lengths */
-                wlen = 16;
                 regs->rcr2      |= RWDLEN2(OMAP_MCBSP_WORD_16);
                 regs->rcr1      |= RWDLEN1(OMAP_MCBSP_WORD_16);
                 regs->xcr2      |= XWDLEN2(OMAP_MCBSP_WORD_16);
@@ -427,7 +478,6 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
                 break;
         case SNDRV_PCM_FORMAT_S32_LE:
                 /* Set word lengths */
-                wlen = 32;
                 regs->rcr2      |= RWDLEN2(OMAP_MCBSP_WORD_32);
                 regs->rcr1      |= RWDLEN1(OMAP_MCBSP_WORD_32);
                 regs->xcr2      |= XWDLEN2(OMAP_MCBSP_WORD_32);