3 files changed, 172 insertions, 181 deletions

diff --git a/sound/arm/aaci.c b/sound/arm/aaci.c
index 91acc9a243ec..d0cead38d5fb 100644
--- a/sound/arm/aaci.c
+++ b/sound/arm/aaci.c
@@ -30,6 +30,8 @@
 
 #define DRIVER_NAME     "aaci-pl041"
 
+#define FRAME_PERIOD_US 21
+
 /*
  * PM support is not complete.  Turn it off.
  */
@@ -48,7 +50,11 @@ static void aaci_ac97_select_codec(struct aaci *aaci, struct snd_ac97 *ac97)
         if (v & SLFR_1RXV)
                 readl(aaci->base + AACI_SL1RX);
 
-        writel(maincr, aaci->base + AACI_MAINCR);
+        if (maincr != readl(aaci->base + AACI_MAINCR)) {
+                writel(maincr, aaci->base + AACI_MAINCR);
+                readl(aaci->base + AACI_MAINCR);
+                udelay(1);
+        }
 }
 
 /*
@@ -64,8 +70,8 @@ static void aaci_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
                             unsigned short val)
 {
         struct aaci *aaci = ac97->private_data;
+        int timeout;
         u32 v;
-        int timeout = 5000;
 
         if (ac97->num >= 4)
                 return;
@@ -81,14 +87,17 @@ static void aaci_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
         writel(val << 4, aaci->base + AACI_SL2TX);
         writel(reg << 12, aaci->base + AACI_SL1TX);
 
-        /*
-         * Wait for the transmission of both slots to complete.
-         */
+        /* Initially, wait one frame period */
+        udelay(FRAME_PERIOD_US);
+
+        /* And then wait an additional eight frame periods for it to be sent */
+        timeout = FRAME_PERIOD_US * 8;
         do {
+                udelay(1);
                 v = readl(aaci->base + AACI_SLFR);
         } while ((v & (SLFR_1TXB|SLFR_2TXB)) && --timeout);
 
-        if (!timeout)
+        if (v & (SLFR_1TXB|SLFR_2TXB))
                 dev_err(&aaci->dev->dev,
                         "timeout waiting for write to complete\n");
 
@@ -101,9 +110,8 @@ static void aaci_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
 static unsigned short aaci_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
 {
         struct aaci *aaci = ac97->private_data;
+        int timeout, retries = 10;
         u32 v;
-        int timeout = 5000;
-        int retries = 10;
 
         if (ac97->num >= 4)
                 return ~0;
@@ -117,35 +125,34 @@ static unsigned short aaci_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
          */
         writel((reg << 12) | (1 << 19), aaci->base + AACI_SL1TX);
 
-        /*
-         * Wait for the transmission to complete.
-         */
+        /* Initially, wait one frame period */
+        udelay(FRAME_PERIOD_US);
+
+        /* And then wait an additional eight frame periods for it to be sent */
+        timeout = FRAME_PERIOD_US * 8;
         do {
+                udelay(1);
                 v = readl(aaci->base + AACI_SLFR);
         } while ((v & SLFR_1TXB) && --timeout);
 
-        if (!timeout) {
+        if (v & SLFR_1TXB) {
                 dev_err(&aaci->dev->dev, "timeout on slot 1 TX busy\n");
                 v = ~0;
                 goto out;
         }
 
-        /*
-         * Give the AC'97 codec more than enough time
-         * to respond. (42us = ~2 frames at 48kHz.)
-         */
-        udelay(42);
+        /* Now wait for the response frame */
+        udelay(FRAME_PERIOD_US);
 
-        /*
-         * Wait for slot 2 to indicate data.
-         */
-        timeout = 5000;
+        /* And then wait an additional eight frame periods for data */
+        timeout = FRAME_PERIOD_US * 8;
         do {
+                udelay(1);
                 cond_resched();
                 v = readl(aaci->base + AACI_SLFR) & (SLFR_1RXV|SLFR_2RXV);
         } while ((v != (SLFR_1RXV|SLFR_2RXV)) && --timeout);
 
-        if (!timeout) {
+        if (v != (SLFR_1RXV|SLFR_2RXV)) {
                 dev_err(&aaci->dev->dev, "timeout on RX valid\n");
                 v = ~0;
                 goto out;
@@ -179,6 +186,7 @@ aaci_chan_wait_ready(struct aaci_runtime *aacirun, unsigned long mask)
         int timeout = 5000;
 
         do {
+                udelay(1);
                 val = readl(aacirun->base + AACI_SR);
         } while (val & mask && timeout--);
 }
@@ -202,6 +210,7 @@ static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
 
         if (mask & ISR_RXINTR) {
                 struct aaci_runtime *aacirun = &aaci->capture;
+                bool period_elapsed = false;
                 void *ptr;
 
                 if (!aacirun->substream || !aacirun->start) {
@@ -214,15 +223,12 @@ static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
 
                 ptr = aacirun->ptr;
                 do {
-                        unsigned int len = aacirun->fifosz;
+                        unsigned int len = aacirun->fifo_bytes;
                         u32 val;
 
                         if (aacirun->bytes <= 0) {
                                 aacirun->bytes += aacirun->period;
-                                aacirun->ptr = ptr;
-                                spin_unlock(&aacirun->lock);
-                                snd_pcm_period_elapsed(aacirun->substream);
-                                spin_lock(&aacirun->lock);
+                                period_elapsed = true;
                         }
                         if (!(aacirun->cr & CR_EN))
                                 break;
@@ -252,6 +258,9 @@ static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
                 aacirun->ptr = ptr;
 
                 spin_unlock(&aacirun->lock);
+
+                if (period_elapsed)
+                        snd_pcm_period_elapsed(aacirun->substream);
         }
 
         if (mask & ISR_URINTR) {
@@ -261,6 +270,7 @@ static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
 
         if (mask & ISR_TXINTR) {
                 struct aaci_runtime *aacirun = &aaci->playback;
+                bool period_elapsed = false;
                 void *ptr;
 
                 if (!aacirun->substream || !aacirun->start) {
@@ -273,15 +283,12 @@ static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
 
                 ptr = aacirun->ptr;
                 do {
-                        unsigned int len = aacirun->fifosz;
+                        unsigned int len = aacirun->fifo_bytes;
                         u32 val;
 
                         if (aacirun->bytes <= 0) {
                                 aacirun->bytes += aacirun->period;
-                                aacirun->ptr = ptr;
-                                spin_unlock(&aacirun->lock);
-                                snd_pcm_period_elapsed(aacirun->substream);
-                                spin_lock(&aacirun->lock);
+                                period_elapsed = true;
                         }
                         if (!(aacirun->cr & CR_EN))
                                 break;
@@ -311,6 +318,9 @@ static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
                 aacirun->ptr = ptr;
 
                 spin_unlock(&aacirun->lock);
+
+                if (period_elapsed)
+                        snd_pcm_period_elapsed(aacirun->substream);
         }
 }
 
@@ -353,7 +363,7 @@ static struct snd_pcm_hardware aaci_hw_info = {
 
         /* rates are setup from the AC'97 codec */
         .channels_min           = 2,
-        .channels_max           = 6,
+        .channels_max           = 2,
         .buffer_bytes_max       = 64 * 1024,
         .period_bytes_min       = 256,
         .period_bytes_max       = PAGE_SIZE,
@@ -361,12 +371,46 @@ static struct snd_pcm_hardware aaci_hw_info = {
         .periods_max            = PAGE_SIZE / 16,
 };
 
-static int __aaci_pcm_open(struct aaci *aaci,
-                           struct snd_pcm_substream *substream,
-                           struct aaci_runtime *aacirun)
+/*
+ * We can support two and four channel audio.  Unfortunately
+ * six channel audio requires a non-standard channel ordering:
+ *   2 -> FL(3), FR(4)
+ *   4 -> FL(3), FR(4), SL(7), SR(8)
+ *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)
+ *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)
+ * This requires an ALSA configuration file to correct.
+ */
+static int aaci_rule_channels(struct snd_pcm_hw_params *p,
+        struct snd_pcm_hw_rule *rule)
+{
+        static unsigned int channel_list[] = { 2, 4, 6 };
+        struct aaci *aaci = rule->private;
+        unsigned int mask = 1 << 0, slots;
+
+        /* pcms[0] is the our 5.1 PCM instance. */
+        slots = aaci->ac97_bus->pcms[0].r[0].slots;
+        if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {
+                mask |= 1 << 1;
+                if (slots & (1 << AC97_SLOT_LFE))
+                        mask |= 1 << 2;
+        }
+
+        return snd_interval_list(hw_param_interval(p, rule->var),
+                                 ARRAY_SIZE(channel_list), channel_list, mask);
+}
+
+static int aaci_pcm_open(struct snd_pcm_substream *substream)
 {
         struct snd_pcm_runtime *runtime = substream->runtime;
-        int ret;
+        struct aaci *aaci = substream->private_data;
+        struct aaci_runtime *aacirun;
+        int ret = 0;
+
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+                aacirun = &aaci->playback;
+        } else {
+                aacirun = &aaci->capture;
+        }
 
         aacirun->substream = substream;
         runtime->private_data = aacirun;
@@ -374,27 +418,37 @@ static int __aaci_pcm_open(struct aaci *aaci,
         runtime->hw.rates = aacirun->pcm->rates;
         snd_pcm_limit_hw_rates(runtime);
 
-        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
-            aacirun->pcm->r[1].slots)
-                snd_ac97_pcm_double_rate_rules(runtime);
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+                runtime->hw.channels_max = 6;
+
+                /* Add rule describing channel dependency. */
+                ret = snd_pcm_hw_rule_add(substream->runtime, 0,
+                                          SNDRV_PCM_HW_PARAM_CHANNELS,
+                                          aaci_rule_channels, aaci,
+                                          SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+                if (ret)
+                        return ret;
+
+                if (aacirun->pcm->r[1].slots)
+                        snd_ac97_pcm_double_rate_rules(runtime);
+        }
 
         /*
-         * FIXME: ALSA specifies fifo_size in bytes.  If we're in normal
-         * mode, each 32-bit word contains one sample.  If we're in
-         * compact mode, each 32-bit word contains two samples, effectively
-         * halving the FIFO size.  However, we don't know for sure which
-         * we'll be using at this point.  We set this to the lower limit.
+         * ALSA wants the byte-size of the FIFOs.  As we only support
+         * 16-bit samples, this is twice the FIFO depth irrespective
+         * of whether it's in compact mode or not.
          */
-        runtime->hw.fifo_size = aaci->fifosize * 2;
-
-        ret = request_irq(aaci->dev->irq[0], aaci_irq, IRQF_SHARED|IRQF_DISABLED,
-                          DRIVER_NAME, aaci);
-        if (ret)
-                goto out;
-
-        return 0;
+        runtime->hw.fifo_size = aaci->fifo_depth * 2;
+
+        mutex_lock(&aaci->irq_lock);
+        if (!aaci->users++) {
+                ret = request_irq(aaci->dev->irq[0], aaci_irq,
+                           IRQF_SHARED | IRQF_DISABLED, DRIVER_NAME, aaci);
+                if (ret != 0)
+                        aaci->users--;
+        }
+        mutex_unlock(&aaci->irq_lock);
 
- out:
         return ret;
 }
 
@@ -410,7 +464,11 @@ static int aaci_pcm_close(struct snd_pcm_substream *substream)
         WARN_ON(aacirun->cr & CR_EN);
 
         aacirun->substream = NULL;
-        free_irq(aaci->dev->irq[0], aaci);
+
+        mutex_lock(&aaci->irq_lock);
+        if (!--aaci->users)
+                free_irq(aaci->dev->irq[0], aaci);
+        mutex_unlock(&aaci->irq_lock);
 
         return 0;
 }
@@ -436,12 +494,21 @@ static int aaci_pcm_hw_free(struct snd_pcm_substream *substream)
         return 0;
 }
 
+/* Channel to slot mask */
+static const u32 channels_to_slotmask[] = {
+        [2] = CR_SL3 | CR_SL4,
+        [4] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8,
+        [6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,
+};
+
 static int aaci_pcm_hw_params(struct snd_pcm_substream *substream,
-                              struct aaci_runtime *aacirun,
                               struct snd_pcm_hw_params *params)
 {
+        struct aaci_runtime *aacirun = substream->runtime->private_data;
+        unsigned int channels = params_channels(params);
+        unsigned int rate = params_rate(params);
+        int dbl = rate > 48000;
         int err;
-        struct aaci *aaci = substream->private_data;
 
         aaci_pcm_hw_free(substream);
         if (aacirun->pcm_open) {
@@ -449,22 +516,28 @@ static int aaci_pcm_hw_params(struct snd_pcm_substream *substream,
                 aacirun->pcm_open = 0;
         }
 
+        /* channels is already limited to 2, 4, or 6 by aaci_rule_channels */
+        if (dbl && channels != 2)
+                return -EINVAL;
+
         err = snd_pcm_lib_malloc_pages(substream,
                                        params_buffer_bytes(params));
         if (err >= 0) {
-                unsigned int rate = params_rate(params);
-                int dbl = rate > 48000;
+                struct aaci *aaci = substream->private_data;
 
-                err = snd_ac97_pcm_open(aacirun->pcm, rate,
-                                        params_channels(params),
+                err = snd_ac97_pcm_open(aacirun->pcm, rate, channels,
                                         aacirun->pcm->r[dbl].slots);
 
                 aacirun->pcm_open = err == 0;
                 aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;
-                aacirun->fifosz = aaci->fifosize * 4;
-
-                if (aacirun->cr & CR_COMPACT)
-                        aacirun->fifosz >>= 1;
+                aacirun->cr |= channels_to_slotmask[channels + dbl * 2];
+
+                /*
+                 * fifo_bytes is the number of bytes we transfer to/from
+                 * the FIFO, including padding.  So that's x4.  As we're
+                 * in compact mode, the FIFO is half the size.
+                 */
+                aacirun->fifo_bytes = aaci->fifo_depth * 4 / 2;
         }
 
         return err;
@@ -475,11 +548,11 @@ static int aaci_pcm_prepare(struct snd_pcm_substream *substream)
         struct snd_pcm_runtime *runtime = substream->runtime;
         struct aaci_runtime *aacirun = runtime->private_data;
 
+        aacirun->period = snd_pcm_lib_period_bytes(substream);
         aacirun->start  = runtime->dma_area;
         aacirun->end    = aacirun->start + snd_pcm_lib_buffer_bytes(substream);
         aacirun->ptr    = aacirun->start;
-        aacirun->period =
-        aacirun->bytes  = frames_to_bytes(runtime, runtime->period_size);
+        aacirun->bytes  = aacirun->period;
 
         return 0;
 }
@@ -497,89 +570,6 @@ static snd_pcm_uframes_t aaci_pcm_pointer(struct snd_pcm_substream *substream)
 /*
  * Playback specific ALSA stuff
  */
-static const u32 channels_to_txmask[] = {
-        [2] = CR_SL3 | CR_SL4,
-        [4] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8,
-        [6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,
-};
-
-/*
- * We can support two and four channel audio.  Unfortunately
- * six channel audio requires a non-standard channel ordering:
- *   2 -> FL(3), FR(4)
- *   4 -> FL(3), FR(4), SL(7), SR(8)
- *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)
- *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)
- * This requires an ALSA configuration file to correct.
- */
-static unsigned int channel_list[] = { 2, 4, 6 };
-
-static int
-aaci_rule_channels(struct snd_pcm_hw_params *p, struct snd_pcm_hw_rule *rule)
-{
-        struct aaci *aaci = rule->private;
-        unsigned int chan_mask = 1 << 0, slots;
-
-        /*
-         * pcms[0] is the our 5.1 PCM instance.
-         */
-        slots = aaci->ac97_bus->pcms[0].r[0].slots;
-        if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {
-                chan_mask |= 1 << 1;
-                if (slots & (1 << AC97_SLOT_LFE))
-                        chan_mask |= 1 << 2;
-        }
-
-        return snd_interval_list(hw_param_interval(p, rule->var),
-                                 ARRAY_SIZE(channel_list), channel_list,
-                                 chan_mask);
-}
-
-static int aaci_pcm_open(struct snd_pcm_substream *substream)
-{
-        struct aaci *aaci = substream->private_data;
-        int ret;
-
-        /*
-         * Add rule describing channel dependency.
-         */
-        ret = snd_pcm_hw_rule_add(substream->runtime, 0,
-                                  SNDRV_PCM_HW_PARAM_CHANNELS,
-                                  aaci_rule_channels, aaci,
-                                  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
-        if (ret)
-                return ret;
-
-        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-                ret = __aaci_pcm_open(aaci, substream, &aaci->playback);
-        } else {
-                ret = __aaci_pcm_open(aaci, substream, &aaci->capture);
-        }
-        return ret;
-}
-
-static int aaci_pcm_playback_hw_params(struct snd_pcm_substream *substream,
-                                       struct snd_pcm_hw_params *params)
-{
-        struct aaci_runtime *aacirun = substream->runtime->private_data;
-        unsigned int channels = params_channels(params);
-        int ret;
-
-        WARN_ON(channels >= ARRAY_SIZE(channels_to_txmask) ||
-                !channels_to_txmask[channels]);
-
-        ret = aaci_pcm_hw_params(substream, aacirun, params);
-
-        /*
-         * Enable FIFO, compact mode, 16 bits per sample.
-         * FIXME: double rate slots?
-         */
-        if (ret >= 0)
-                aacirun->cr |= channels_to_txmask[channels];
-
-        return ret;
-}
-
 static void aaci_pcm_playback_stop(struct aaci_runtime *aacirun)
 {
         u32 ie;
@@ -649,27 +639,13 @@ static struct snd_pcm_ops aaci_playback_ops = {
         .open           = aaci_pcm_open,
         .close          = aaci_pcm_close,
         .ioctl          = snd_pcm_lib_ioctl,
-        .hw_params      = aaci_pcm_playback_hw_params,
+        .hw_params      = aaci_pcm_hw_params,
         .hw_free        = aaci_pcm_hw_free,
         .prepare        = aaci_pcm_prepare,
         .trigger        = aaci_pcm_playback_trigger,
         .pointer        = aaci_pcm_pointer,
 };
 
-static int aaci_pcm_capture_hw_params(struct snd_pcm_substream *substream,
-                                      struct snd_pcm_hw_params *params)
-{
-        struct aaci_runtime *aacirun = substream->runtime->private_data;
-        int ret;
-
-        ret = aaci_pcm_hw_params(substream, aacirun, params);
-        if (ret >= 0)
-                /* Line in record: slot 3 and 4 */
-                aacirun->cr |= CR_SL3 | CR_SL4;
-
-        return ret;
-}
-
 static void aaci_pcm_capture_stop(struct aaci_runtime *aacirun)
 {
         u32 ie;
@@ -766,7 +742,7 @@ static struct snd_pcm_ops aaci_capture_ops = {
         .open           = aaci_pcm_open,
         .close          = aaci_pcm_close,
         .ioctl          = snd_pcm_lib_ioctl,
-        .hw_params      = aaci_pcm_capture_hw_params,
+        .hw_params      = aaci_pcm_hw_params,
         .hw_free        = aaci_pcm_hw_free,
         .prepare        = aaci_pcm_capture_prepare,
         .trigger        = aaci_pcm_capture_trigger,
@@ -874,7 +850,7 @@ static int __devinit aaci_probe_ac97(struct aaci *aaci)
          * Give the AC'97 codec more than enough time
          * to wake up. (42us = ~2 frames at 48kHz.)
          */
-        udelay(42);
+        udelay(FRAME_PERIOD_US * 2);
 
         ret = snd_ac97_bus(aaci->card, 0, &aaci_bus_ops, aaci, &ac97_bus);
         if (ret)
@@ -933,12 +909,13 @@ static struct aaci * __devinit aaci_init_card(struct amba_device *dev)
         strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
         strlcpy(card->shortname, "ARM AC'97 Interface", sizeof(card->shortname));
         snprintf(card->longname, sizeof(card->longname),
-                 "%s at 0x%016llx, irq %d",
-                 card->shortname, (unsigned long long)dev->res.start,
-                 dev->irq[0]);
+                 "%s PL%03x rev%u at 0x%08llx, irq %d",
+                 card->shortname, amba_part(dev), amba_rev(dev),
+                 (unsigned long long)dev->res.start, dev->irq[0]);
 
         aaci = card->private_data;
         mutex_init(&aaci->ac97_sem);
+        mutex_init(&aaci->irq_lock);
         aaci->card = card;
         aaci->dev = dev;
 
@@ -976,6 +953,10 @@ static unsigned int __devinit aaci_size_fifo(struct aaci *aaci)
         struct aaci_runtime *aacirun = &aaci->playback;
         int i;
 
+        /*
+         * Enable the channel, but don't assign it to any slots, so
+         * it won't empty onto the AC'97 link.
+         */
         writel(CR_FEN | CR_SZ16 | CR_EN, aacirun->base + AACI_TXCR);
 
         for (i = 0; !(readl(aacirun->base + AACI_SR) & SR_TXFF) && i < 4096; i++)
@@ -989,10 +970,12 @@ static unsigned int __devinit aaci_size_fifo(struct aaci *aaci)
          * disabling the channel doesn't clear the FIFO.
          */
         writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR);
+        readl(aaci->base + AACI_MAINCR);
+        udelay(1);
         writel(aaci->maincr, aaci->base + AACI_MAINCR);
 
         /*
-         * If we hit 4096, we failed.  Go back to the specified
+         * If we hit 4096 entries, we failed.  Go back to the specified
          * fifo depth.
          */
         if (i == 4096)
@@ -1001,7 +984,8 @@ static unsigned int __devinit aaci_size_fifo(struct aaci *aaci)
         return i;
 }
 
-static int __devinit aaci_probe(struct amba_device *dev, struct amba_id *id)
+static int __devinit aaci_probe(struct amba_device *dev,
+        const struct amba_id *id)
 {
         struct aaci *aaci;
         int ret, i;
@@ -1057,11 +1041,12 @@ static int __devinit aaci_probe(struct amba_device *dev, struct amba_id *id)
 
         /*
          * Size the FIFOs (must be multiple of 16).
+         * This is the number of entries in the FIFO.
          */
-        aaci->fifosize = aaci_size_fifo(aaci);
-        if (aaci->fifosize & 15) {
-                printk(KERN_WARNING "AACI: fifosize = %d not supported\n",
-                       aaci->fifosize);
+        aaci->fifo_depth = aaci_size_fifo(aaci);
+        if (aaci->fifo_depth & 15) {
+                printk(KERN_WARNING "AACI: FIFO depth %d not supported\n",
+                       aaci->fifo_depth);
                 ret = -ENODEV;
                 goto out;
         }
@@ -1074,8 +1059,8 @@ static int __devinit aaci_probe(struct amba_device *dev, struct amba_id *id)
 
         ret = snd_card_register(aaci->card);
         if (ret == 0) {
-                dev_info(&dev->dev, "%s, fifo %d\n", aaci->card->longname,
-                         aaci->fifosize);
+                dev_info(&dev->dev, "%s\n", aaci->card->longname);
+                dev_info(&dev->dev, "FIFO %u entries\n", aaci->fifo_depth);
                 amba_set_drvdata(dev, aaci->card);
                 return ret;
         }
diff --git a/sound/arm/aaci.h b/sound/arm/aaci.h
index 6a4a2eebdda1..5791bd5bd2ab 100644
--- a/sound/arm/aaci.h
+++ b/sound/arm/aaci.h
@@ -210,6 +210,8 @@ struct aaci_runtime {
         u32                     cr;
         struct snd_pcm_substream        *substream;
 
+        unsigned int            period; /* byte size of a "period" */
+
         /*
          * PIO support
          */
@@ -217,15 +219,16 @@ struct aaci_runtime {
         void                    *end;
         void                    *ptr;
         int                     bytes;
-        unsigned int            period;
-        unsigned int            fifosz;
+        unsigned int            fifo_bytes;
 };
 
 struct aaci {
         struct amba_device      *dev;
         struct snd_card         *card;
         void                    __iomem *base;
-        unsigned int            fifosize;
+        unsigned int            fifo_depth;
+        unsigned int            users;
+        struct mutex            irq_lock;
 
         /* AC'97 */
         struct mutex            ac97_sem;
diff --git a/sound/arm/pxa2xx-pcm-lib.c b/sound/arm/pxa2xx-pcm-lib.c
index 8808b82311b1..76e0d5695075 100644
--- a/sound/arm/pxa2xx-pcm-lib.c
+++ b/sound/arm/pxa2xx-pcm-lib.c
@@ -140,6 +140,9 @@ int __pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
         if (!prtd || !prtd->params)
                 return 0;
 
+        if (prtd->dma_ch == -1)
+                return -EINVAL;
+
         DCSR(prtd->dma_ch) &= ~DCSR_RUN;
         DCSR(prtd->dma_ch) = 0;
         DCMD(prtd->dma_ch) = 0;