4 files changed, 274 insertions, 0 deletions

diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h
index d015d67e75c3..e0bf24e90669 100644
--- a/include/sound/dmaengine_pcm.h
+++ b/include/sound/dmaengine_pcm.h
@@ -72,4 +72,29 @@ void snd_dmaengine_pcm_set_config_from_dai_data(
         const struct snd_dmaengine_dai_dma_data *dma_data,
         struct dma_slave_config *config);
 
+/**
+ * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
+ * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
+ *   PCM substream. Will be called from the PCM drivers hwparams callback.
+ * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
+ * @prealloc_buffer_size: Size of the preallocated audio buffer.
+ */
+struct snd_dmaengine_pcm_config {
+        int (*prepare_slave_config)(struct snd_pcm_substream *substream,
+                        struct snd_pcm_hw_params *params,
+                        struct dma_slave_config *slave_config);
+
+        const struct snd_pcm_hardware *pcm_hardware;
+        unsigned int prealloc_buffer_size;
+};
+
+int snd_dmaengine_pcm_register(struct device *dev,
+        const struct snd_dmaengine_pcm_config *config,
+        unsigned int flags);
+void snd_dmaengine_pcm_unregister(struct device *dev);
+
+int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
+        struct snd_pcm_hw_params *params,
+        struct dma_slave_config *slave_config);
+
 #endif
diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig
index 5da8ca7aee05..9e675c76436c 100644
--- a/sound/soc/Kconfig
+++ b/sound/soc/Kconfig
@@ -29,6 +29,10 @@ config SND_SOC_AC97_BUS
 config SND_SOC_DMAENGINE_PCM
         bool
 
+config SND_SOC_GENERIC_DMAENGINE_PCM
+        bool
+        select SND_SOC_DMAENGINE_PCM
+
 # All the supported SoCs
 source "sound/soc/atmel/Kconfig"
 source "sound/soc/au1x/Kconfig"
diff --git a/sound/soc/Makefile b/sound/soc/Makefile
index 99f32f7c0692..197b6ae54c8d 100644
--- a/sound/soc/Makefile
+++ b/sound/soc/Makefile
@@ -5,6 +5,10 @@ ifneq ($(CONFIG_SND_SOC_DMAENGINE_PCM),)
 snd-soc-core-objs += soc-dmaengine-pcm.o
 endif
 
+ifneq ($(CONFIG_SND_SOC_GENERIC_DMAENGINE_PCM),)
+snd-soc-core-objs += soc-generic-dmaengine-pcm.o
+endif
+
 obj-$(CONFIG_SND_SOC)   += snd-soc-core.o
 obj-$(CONFIG_SND_SOC)   += codecs/
 obj-$(CONFIG_SND_SOC)   += generic/
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
new file mode 100644
index 000000000000..acfc92698995
--- /dev/null
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -0,0 +1,241 @@
+/*
+ *  Copyright (C) 2013, Analog Devices Inc.
+ *      Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/dmaengine.h>
+#include <linux/slab.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <linux/dma-mapping.h>
+#include <linux/of.h>
+#include <linux/of_dma.h>
+
+#include <sound/dmaengine_pcm.h>
+
+struct dmaengine_pcm {
+        struct dma_chan *chan[SNDRV_PCM_STREAM_CAPTURE + 1];
+        const struct snd_dmaengine_pcm_config *config;
+        struct snd_soc_platform platform;
+};
+
+static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p)
+{
+        return container_of(p, struct dmaengine_pcm, platform);
+}
+
+/**
+ * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
+ * @substream: PCM substream
+ * @params: hw_params
+ * @slave_config: DMA slave config to prepare
+ *
+ * This function can be used as a generic prepare_slave_config callback for
+ * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
+ * DAI DMA data. Internally the function will first call
+ * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
+ * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
+ * remaining fields based on the DAI DMA data.
+ */
+int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
+        struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct snd_dmaengine_dai_dma_data *dma_data;
+        int ret;
+
+        dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+
+        ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
+        if (ret)
+                return ret;
+
+        snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
+                slave_config);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
+
+static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream,
+        struct snd_pcm_hw_params *params)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+        struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
+        struct dma_slave_config slave_config;
+        int ret;
+
+        if (pcm->config->prepare_slave_config) {
+                ret = pcm->config->prepare_slave_config(substream, params,
+                                &slave_config);
+                if (ret)
+                        return ret;
+
+                ret = dmaengine_slave_config(chan, &slave_config);
+                if (ret)
+                        return ret;
+        }
+
+        return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
+}
+
+static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+        struct dma_chan *chan = pcm->chan[substream->stream];
+        int ret;
+
+        ret = snd_soc_set_runtime_hwparams(substream,
+                                pcm->config->pcm_hardware);
+        if (ret)
+                return ret;
+
+        return snd_dmaengine_pcm_open(substream, chan);
+}
+
+static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
+        struct snd_pcm_substream *substream)
+{
+        if (!pcm->chan[substream->stream])
+                return NULL;
+
+        return pcm->chan[substream->stream]->device->dev;
+}
+
+static void dmaengine_pcm_free(struct snd_pcm *pcm)
+{
+        snd_pcm_lib_preallocate_free_for_all(pcm);
+}
+
+static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
+{
+        struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+        const struct snd_dmaengine_pcm_config *config = pcm->config;
+        struct snd_pcm_substream *substream;
+        unsigned int i;
+        int ret;
+
+        for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
+                substream = rtd->pcm->streams[i].substream;
+                if (!substream)
+                        continue;
+
+                if (!pcm->chan[i]) {
+                        dev_err(rtd->platform->dev,
+                                "Missing dma channel for stream: %d\n", i);
+                        ret = -EINVAL;
+                        goto err_free;
+                }
+
+                ret = snd_pcm_lib_preallocate_pages(substream,
+                                SNDRV_DMA_TYPE_DEV,
+                                dmaengine_dma_dev(pcm, substream),
+                                config->prealloc_buffer_size,
+                                config->pcm_hardware->buffer_bytes_max);
+                if (ret)
+                        goto err_free;
+        }
+
+        return 0;
+
+err_free:
+        dmaengine_pcm_free(rtd->pcm);
+        return ret;
+}
+
+static const struct snd_pcm_ops dmaengine_pcm_ops = {
+        .open           = dmaengine_pcm_open,
+        .close          = snd_dmaengine_pcm_close,
+        .ioctl          = snd_pcm_lib_ioctl,
+        .hw_params      = dmaengine_pcm_hw_params,
+        .hw_free        = snd_pcm_lib_free_pages,
+        .trigger        = snd_dmaengine_pcm_trigger,
+        .pointer        = snd_dmaengine_pcm_pointer,
+};
+
+static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
+        .ops            = &dmaengine_pcm_ops,
+        .pcm_new        = dmaengine_pcm_new,
+        .pcm_free       = dmaengine_pcm_free,
+};
+
+static const char * const dmaengine_pcm_dma_channel_names[] = {
+        [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
+        [SNDRV_PCM_STREAM_CAPTURE] = "rx",
+};
+
+/**
+ * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
+ * @dev: The parent device for the PCM device
+ * @config: Platform specific PCM configuration
+ * @flags: Platform specific quirks
+ */
+int snd_dmaengine_pcm_register(struct device *dev,
+        const struct snd_dmaengine_pcm_config *config, unsigned int flags)
+{
+        struct dmaengine_pcm *pcm;
+        unsigned int i;
+
+        if (!dev->of_node)
+                return -EINVAL;
+
+        pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
+        if (!pcm)
+                return -ENOMEM;
+
+        pcm->config = config;
+
+        for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
+                pcm->chan[i] = of_dma_request_slave_channel(dev->of_node,
+                                        dmaengine_pcm_dma_channel_names[i]);
+        }
+
+        return snd_soc_add_platform(dev, &pcm->platform,
+                                &dmaengine_pcm_platform);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
+
+/**
+ * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
+ * @dev: Parent device the PCM was register with
+ *
+ * Removes a dmaengine based PCM device previously registered with
+ * snd_dmaengine_pcm_register.
+ */
+void snd_dmaengine_pcm_unregister(struct device *dev)
+{
+        struct snd_soc_platform *platform;
+        struct dmaengine_pcm *pcm;
+        unsigned int i;
+
+        platform = snd_soc_lookup_platform(dev);
+        if (!platform)
+                return;
+
+        pcm = soc_platform_to_pcm(platform);
+
+        for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
+                if (pcm->chan[i])
+                        dma_release_channel(pcm->chan[i]);
+        }
+
+        snd_soc_remove_platform(platform);
+        kfree(pcm);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
+
+MODULE_LICENSE("GPL");