ASoC: Add support for SPEAr ASoC pcm layer.

This patch add support for the SPEAr ASoC pcm layer in ASoC
framework. The pcm layer uses common snd_dmaengine framework.

Signed-off-by: Rajeev Kumar <rajeev-dlh.kumar@st.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 214 insertions, 0 deletions

diff --git a/sound/soc/spear/spear_pcm.c b/sound/soc/spear/spear_pcm.c
new file mode 100644
index 000000000000..97c2cac8e92c
--- /dev/null
+++ b/sound/soc/spear/spear_pcm.c
@@ -0,0 +1,214 @@
+/*
+ * ALSA PCM interface for ST SPEAr Processors
+ *
+ * sound/soc/spear/spear_pcm.c
+ *
+ * Copyright (C) 2012 ST Microelectronics
+ * Rajeev Kumar<rajeev-dlh.kumar@st.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/spear_dma.h>
+
+struct snd_pcm_hardware spear_pcm_hardware = {
+        .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+                 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+                 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME),
+        .buffer_bytes_max = 16 * 1024, /* max buffer size */
+        .period_bytes_min = 2 * 1024, /* 1 msec data minimum period size */
+        .period_bytes_max = 2 * 1024, /* maximum period size */
+        .periods_min = 1, /* min # periods */
+        .periods_max = 8, /* max # of periods */
+        .fifo_size = 0, /* fifo size in bytes */
+};
+
+static int spear_pcm_hw_params(struct snd_pcm_substream *substream,
+                struct snd_pcm_hw_params *params)
+{
+        snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+
+        return 0;
+}
+
+static int spear_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+        snd_pcm_set_runtime_buffer(substream, NULL);
+
+        return 0;
+}
+
+static int spear_pcm_open(struct snd_pcm_substream *substream)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+
+        struct spear_dma_data *dma_data = (struct spear_dma_data *)
+                snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+        int ret;
+
+        ret = snd_soc_set_runtime_hwparams(substream, &spear_pcm_hardware);
+        if (ret)
+                return ret;
+
+        ret = snd_dmaengine_pcm_open(substream, dma_data->filter, dma_data);
+        if (ret)
+                return ret;
+
+        snd_dmaengine_pcm_set_data(substream, dma_data);
+
+        return 0;
+}
+
+static int spear_pcm_close(struct snd_pcm_substream *substream)
+{
+
+        snd_dmaengine_pcm_close(substream);
+
+        return 0;
+}
+
+static int spear_pcm_mmap(struct snd_pcm_substream *substream,
+                struct vm_area_struct *vma)
+{
+        struct snd_pcm_runtime *runtime = substream->runtime;
+
+        return dma_mmap_writecombine(substream->pcm->card->dev, vma,
+                        runtime->dma_area, runtime->dma_addr,
+                        runtime->dma_bytes);
+}
+
+static struct snd_pcm_ops spear_pcm_ops = {
+        .open           = spear_pcm_open,
+        .close          = spear_pcm_close,
+        .ioctl          = snd_pcm_lib_ioctl,
+        .hw_params      = spear_pcm_hw_params,
+        .hw_free        = spear_pcm_hw_free,
+        .trigger        = snd_dmaengine_pcm_trigger,
+        .pointer        = snd_dmaengine_pcm_pointer,
+        .mmap           = spear_pcm_mmap,
+};
+
+static int
+spear_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream,
+                size_t size)
+{
+        struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+        struct snd_dma_buffer *buf = &substream->dma_buffer;
+
+        buf->dev.type = SNDRV_DMA_TYPE_DEV;
+        buf->dev.dev = pcm->card->dev;
+        buf->private_data = NULL;
+
+        buf->area = dma_alloc_writecombine(pcm->card->dev, size,
+                        &buf->addr, GFP_KERNEL);
+        if (!buf->area)
+                return -ENOMEM;
+
+        dev_info(buf->dev.dev,
+                        " preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
+                        (void *)buf->area, (void *)buf->addr, size);
+
+        buf->bytes = size;
+        return 0;
+}
+
+static void spear_pcm_free(struct snd_pcm *pcm)
+{
+        struct snd_pcm_substream *substream;
+        struct snd_dma_buffer *buf;
+        int stream;
+
+        for (stream = 0; stream < 2; stream++) {
+                substream = pcm->streams[stream].substream;
+                if (!substream)
+                        continue;
+
+                buf = &substream->dma_buffer;
+                if (!buf && !buf->area)
+                        continue;
+
+                dma_free_writecombine(pcm->card->dev, buf->bytes,
+                                buf->area, buf->addr);
+                buf->area = NULL;
+        }
+}
+
+static u64 spear_pcm_dmamask = DMA_BIT_MASK(32);
+
+static int spear_pcm_new(struct snd_card *card,
+                struct snd_soc_dai *dai, struct snd_pcm *pcm)
+{
+        int ret;
+
+        if (!card->dev->dma_mask)
+                card->dev->dma_mask = &spear_pcm_dmamask;
+        if (!card->dev->coherent_dma_mask)
+                card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+        if (dai->driver->playback.channels_min) {
+                ret = spear_pcm_preallocate_dma_buffer(pcm,
+                                SNDRV_PCM_STREAM_PLAYBACK,
+                                spear_pcm_hardware.buffer_bytes_max);
+                if (ret)
+                        return ret;
+        }
+
+        if (dai->driver->capture.channels_min) {
+                ret = spear_pcm_preallocate_dma_buffer(pcm,
+                                SNDRV_PCM_STREAM_CAPTURE,
+                                spear_pcm_hardware.buffer_bytes_max);
+                if (ret)
+                        return ret;
+        }
+
+        return 0;
+}
+
+struct snd_soc_platform_driver spear_soc_platform = {
+        .ops            =       &spear_pcm_ops,
+        .pcm_new        =       spear_pcm_new,
+        .pcm_free       =       spear_pcm_free,
+};
+
+static int __devinit spear_soc_platform_probe(struct platform_device *pdev)
+{
+        return snd_soc_register_platform(&pdev->dev, &spear_soc_platform);
+}
+
+static int __devexit spear_soc_platform_remove(struct platform_device *pdev)
+{
+        snd_soc_unregister_platform(&pdev->dev);
+
+        return 0;
+}
+
+static struct platform_driver spear_pcm_driver = {
+        .driver = {
+                .name = "spear-pcm-audio",
+                .owner = THIS_MODULE,
+        },
+
+        .probe = spear_soc_platform_probe,
+        .remove = __devexit_p(spear_soc_platform_remove),
+};
+
+module_platform_driver(spear_pcm_driver);
+
+MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
+MODULE_DESCRIPTION("SPEAr PCM DMA module");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:spear-pcm-audio");