1 files changed, 63 insertions, 35 deletions

diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index c6d6eb71dc1d..169bca295b78 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -72,6 +72,7 @@
  * @dev: struct device pointer
  * @playback: the number of playback streams opened
  * @capture: the number of capture streams opened
+ * @asynchronous: 0=synchronous mode, 1=asynchronous mode
  * @cpu_dai: the CPU DAI for this device
  * @dev_attr: the sysfs device attribute structure
  * @stats: SSI statistics
@@ -86,6 +87,7 @@ struct fsl_ssi_private {
         struct device *dev;
         unsigned int playback;
         unsigned int capture;
+        int asynchronous;
         struct snd_soc_dai cpu_dai;
         struct device_attribute dev_attr;
 
@@ -301,9 +303,10 @@ static int fsl_ssi_startup(struct snd_pcm_substream *substream,
                  *
                  * FIXME: Little-endian samples require a different shift dir
                  */
-                clrsetbits_be32(&ssi->scr, CCSR_SSI_SCR_I2S_MODE_MASK,
-                        CCSR_SSI_SCR_TFR_CLK_DIS |
-                        CCSR_SSI_SCR_I2S_MODE_SLAVE | CCSR_SSI_SCR_SYN);
+                clrsetbits_be32(&ssi->scr,
+                        CCSR_SSI_SCR_I2S_MODE_MASK | CCSR_SSI_SCR_SYN,
+                        CCSR_SSI_SCR_TFR_CLK_DIS | CCSR_SSI_SCR_I2S_MODE_SLAVE
+                        | (ssi_private->asynchronous ? 0 : CCSR_SSI_SCR_SYN));
 
                 out_be32(&ssi->stcr,
                          CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TFEN0 |
@@ -382,10 +385,15 @@ static int fsl_ssi_startup(struct snd_pcm_substream *substream,
                         SNDRV_PCM_HW_PARAM_RATE,
                         first_runtime->rate, first_runtime->rate);
 
-                snd_pcm_hw_constraint_minmax(substream->runtime,
-                        SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
-                        first_runtime->sample_bits,
-                        first_runtime->sample_bits);
+                /* If we're in synchronous mode, then we need to constrain
+                 * the sample size as well.  We don't support independent sample
+                 * rates in asynchronous mode.
+                 */
+                if (!ssi_private->asynchronous)
+                        snd_pcm_hw_constraint_minmax(substream->runtime,
+                                SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
+                                first_runtime->sample_bits,
+                                first_runtime->sample_bits);
 
                 ssi_private->second_stream = substream;
         }
@@ -400,7 +408,7 @@ static int fsl_ssi_startup(struct snd_pcm_substream *substream,
 }
 
 /**
- * fsl_ssi_prepare: prepare the SSI.
+ * fsl_ssi_hw_params - program the sample size
  *
  * Most of the SSI registers have been programmed in the startup function,
  * but the word length must be programmed here.  Unfortunately, programming
@@ -412,23 +420,27 @@ static int fsl_ssi_startup(struct snd_pcm_substream *substream,
  * Note: The SxCCR.DC and SxCCR.PM bits are only used if the SSI is the
  * clock master.
  */
-static int fsl_ssi_prepare(struct snd_pcm_substream *substream,
-                           struct snd_soc_dai *dai)
+static int fsl_ssi_hw_params(struct snd_pcm_substream *substream,
+        struct snd_pcm_hw_params *hw_params, struct snd_soc_dai *cpu_dai)
 {
-        struct snd_pcm_runtime *runtime = substream->runtime;
-        struct snd_soc_pcm_runtime *rtd = substream->private_data;
-        struct fsl_ssi_private *ssi_private = rtd->dai->cpu_dai->private_data;
-
-        struct ccsr_ssi __iomem *ssi = ssi_private->ssi;
+        struct fsl_ssi_private *ssi_private = cpu_dai->private_data;
 
         if (substream == ssi_private->first_stream) {
-                u32 wl;
+                struct ccsr_ssi __iomem *ssi = ssi_private->ssi;
+                unsigned int sample_size =
+                        snd_pcm_format_width(params_format(hw_params));
+                u32 wl = CCSR_SSI_SxCCR_WL(sample_size);
 
                 /* The SSI should always be disabled at this points (SSIEN=0) */
-                wl = CCSR_SSI_SxCCR_WL(snd_pcm_format_width(runtime->format));
 
                 /* In synchronous mode, the SSI uses STCCR for capture */
-                clrsetbits_be32(&ssi->stccr, CCSR_SSI_SxCCR_WL_MASK, wl);
+                if ((substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ||
+                    !ssi_private->asynchronous)
+                        clrsetbits_be32(&ssi->stccr,
+                                        CCSR_SSI_SxCCR_WL_MASK, wl);
+                else
+                        clrsetbits_be32(&ssi->srccr,
+                                        CCSR_SSI_SxCCR_WL_MASK, wl);
         }
 
         return 0;
@@ -452,28 +464,33 @@ static int fsl_ssi_trigger(struct snd_pcm_substream *substream, int cmd,
 
         switch (cmd) {
         case SNDRV_PCM_TRIGGER_START:
-        case SNDRV_PCM_TRIGGER_RESUME:
+                clrbits32(&ssi->scr, CCSR_SSI_SCR_SSIEN);
         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-                        clrbits32(&ssi->scr, CCSR_SSI_SCR_SSIEN);
                         setbits32(&ssi->scr,
                                 CCSR_SSI_SCR_SSIEN | CCSR_SSI_SCR_TE);
                 } else {
-                        clrbits32(&ssi->scr, CCSR_SSI_SCR_SSIEN);
+                        long timeout = jiffies + 10;
+
                         setbits32(&ssi->scr,
                                 CCSR_SSI_SCR_SSIEN | CCSR_SSI_SCR_RE);
 
-                        /*
-                         * I think we need this delay to allow time for the SSI
-                         * to put data into its FIFO.  Without it, ALSA starts
-                         * to complain about overruns.
+                        /* Wait until the SSI has filled its FIFO. Without this
+                         * delay, ALSA complains about overruns.  When the FIFO
+                         * is full, the DMA controller initiates its first
+                         * transfer.  Until then, however, the DMA's DAR
+                         * register is zero, which translates to an
+                         * out-of-bounds pointer.  This makes ALSA think an
+                         * overrun has occurred.
                          */
-                        mdelay(1);
+                        while (!(in_be32(&ssi->sisr) & CCSR_SSI_SISR_RFF0) &&
+                               (jiffies < timeout));
+                        if (!(in_be32(&ssi->sisr) & CCSR_SSI_SISR_RFF0))
+                                return -EIO;
                 }
                 break;
 
         case SNDRV_PCM_TRIGGER_STOP:
-        case SNDRV_PCM_TRIGGER_SUSPEND:
         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                         clrbits32(&ssi->scr, CCSR_SSI_SCR_TE);
@@ -563,6 +580,15 @@ static int fsl_ssi_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
 /**
  * fsl_ssi_dai_template: template CPU DAI for the SSI
  */
+static struct snd_soc_dai_ops fsl_ssi_dai_ops = {
+        .startup        = fsl_ssi_startup,
+        .hw_params      = fsl_ssi_hw_params,
+        .shutdown       = fsl_ssi_shutdown,
+        .trigger        = fsl_ssi_trigger,
+        .set_sysclk     = fsl_ssi_set_sysclk,
+        .set_fmt        = fsl_ssi_set_fmt,
+};
+
 static struct snd_soc_dai fsl_ssi_dai_template = {
         .playback = {
                 /* The SSI does not support monaural audio. */
@@ -577,14 +603,7 @@ static struct snd_soc_dai fsl_ssi_dai_template = {
                 .rates = FSLSSI_I2S_RATES,
                 .formats = FSLSSI_I2S_FORMATS,
         },
-        .ops = {
-                .startup = fsl_ssi_startup,
-                .prepare = fsl_ssi_prepare,
-                .shutdown = fsl_ssi_shutdown,
-                .trigger = fsl_ssi_trigger,
-                .set_sysclk = fsl_ssi_set_sysclk,
-                .set_fmt = fsl_ssi_set_fmt,
-        },
+        .ops = &fsl_ssi_dai_ops,
 };
 
 /**
@@ -654,6 +673,7 @@ struct snd_soc_dai *fsl_ssi_create_dai(struct fsl_ssi_info *ssi_info)
         ssi_private->ssi_phys = ssi_info->ssi_phys;
         ssi_private->irq = ssi_info->irq;
         ssi_private->dev = ssi_info->dev;
+        ssi_private->asynchronous = ssi_info->asynchronous;
 
         ssi_private->dev->driver_data = fsl_ssi_dai;
 
@@ -704,6 +724,14 @@ void fsl_ssi_destroy_dai(struct snd_soc_dai *fsl_ssi_dai)
 }
 EXPORT_SYMBOL_GPL(fsl_ssi_destroy_dai);
 
+static int __init fsl_ssi_init(void)
+{
+        printk(KERN_INFO "Freescale Synchronous Serial Interface (SSI) ASoC Driver\n");
+
+        return 0;
+}
+module_init(fsl_ssi_init);
+
 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
 MODULE_DESCRIPTION("Freescale Synchronous Serial Interface (SSI) ASoC Driver");
 MODULE_LICENSE("GPL");