[alsa-devel] [PATCH 3/7] ASoC: tegra: Add tegra-pcm driver
Stephen Warren
swarren at nvidia.com
Sat Jan 8 06:36:13 CET 2011
This provides an ASoC platform driver that manages Tegra's APB DMA
controller.
Signed-off-by: Stephen Warren <swarren at nvidia.com>
---
sound/soc/tegra/tegra_pcm.c | 401 +++++++++++++++++++++++++++++++++++++++++++
sound/soc/tegra/tegra_pcm.h | 55 ++++++
2 files changed, 456 insertions(+), 0 deletions(-)
create mode 100644 sound/soc/tegra/tegra_pcm.c
create mode 100644 sound/soc/tegra/tegra_pcm.h
diff --git a/sound/soc/tegra/tegra_pcm.c b/sound/soc/tegra/tegra_pcm.c
new file mode 100644
index 0000000..663ea9f
--- /dev/null
+++ b/sound/soc/tegra/tegra_pcm.c
@@ -0,0 +1,401 @@
+/*
+ * tegra_pcm.c - Tegra PCM driver
+ *
+ * Author: Stephen Warren <swarren at nvidia.com>
+ * Copyright (C) 2010 - NVIDIA, Inc.
+ *
+ * Based on code copyright/by:
+ *
+ * Copyright (c) 2009-2010, NVIDIA Corporation.
+ * Scott Peterson <speterson at nvidia.com>
+ * Vijay Mali <vmali at nvidia.com>
+ *
+ * Copyright (C) 2010 Google, Inc.
+ * Iliyan Malchev <malchev at google.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include "tegra_pcm.h"
+
+static const struct snd_pcm_hardware tegra_pcm_hardware = {
+ .info = SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_PAUSE |
+ SNDRV_PCM_INFO_RESUME |
+ SNDRV_PCM_INFO_INTERLEAVED,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE,
+ .channels_min = 2,
+ .channels_max = 2,
+ .period_bytes_min = 1024,
+ .period_bytes_max = PAGE_SIZE,
+ .periods_min = 2,
+ .periods_max = 8,
+ .buffer_bytes_max = PAGE_SIZE * 8,
+ .fifo_size = 4,
+};
+
+static void tegra_pcm_queue_dma(struct tegra_runtime_data *prtd)
+{
+ struct snd_pcm_substream *substream = prtd->substream;
+ struct snd_dma_buffer *buf = &substream->dma_buffer;
+ struct tegra_dma_req *dma_req;
+ unsigned long addr;
+
+ dma_req = &prtd->dma_req[prtd->dma_req_idx];
+ prtd->dma_req_idx = 1 - prtd->dma_req_idx;
+
+ addr = buf->addr + prtd->dma_pos;
+ prtd->dma_pos += dma_req->size;
+ if (prtd->dma_pos >= prtd->dma_pos_end)
+ prtd->dma_pos = 0;
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+ dma_req->source_addr = addr;
+ else
+ dma_req->dest_addr = addr;
+
+ tegra_dma_enqueue_req(prtd->dma_chan, dma_req);
+}
+
+static void dma_complete_callback(struct tegra_dma_req *req)
+{
+ struct tegra_runtime_data *prtd = (struct tegra_runtime_data *)req->dev;
+ struct snd_pcm_substream *substream = prtd->substream;
+ struct snd_pcm_runtime *runtime = substream->runtime;
+
+ spin_lock(&prtd->lock);
+
+ if (!prtd->running) {
+ spin_unlock(&prtd->lock);
+ return;
+ }
+
+ if (++prtd->period_index >= runtime->periods)
+ prtd->period_index = 0;
+
+ tegra_pcm_queue_dma(prtd);
+
+ spin_unlock(&prtd->lock);
+
+ snd_pcm_period_elapsed(substream);
+}
+
+static void setup_dma_tx_request(struct tegra_dma_req *req,
+ struct tegra_pcm_dma_params * dmap)
+{
+ req->complete = dma_complete_callback;
+ req->to_memory = false;
+ req->dest_addr = dmap->addr;
+ req->dest_wrap = dmap->wrap;
+ req->source_bus_width = 32;
+ req->source_wrap = 0;
+ req->dest_bus_width = dmap->width;
+ req->req_sel = dmap->req_sel;
+}
+
+static void setup_dma_rx_request(struct tegra_dma_req *req,
+ struct tegra_pcm_dma_params * dmap)
+{
+ req->complete = dma_complete_callback;
+ req->to_memory = true;
+ req->source_addr = dmap->addr;
+ req->dest_wrap = 0;
+ req->source_bus_width = dmap->width;
+ req->source_wrap = dmap->wrap;
+ req->dest_bus_width = 32;
+ req->req_sel = dmap->req_sel;
+}
+
+static int tegra_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct tegra_runtime_data *prtd;
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct tegra_pcm_dma_params * dmap;
+ int ret = 0;
+
+ prtd = kzalloc(sizeof(struct tegra_runtime_data), GFP_KERNEL);
+ if (prtd == NULL)
+ return -ENOMEM;
+
+ runtime->private_data = prtd;
+ prtd->substream = substream;
+
+ spin_lock_init(&prtd->lock);
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ dmap = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+ setup_dma_tx_request(&prtd->dma_req[0], dmap);
+ setup_dma_tx_request(&prtd->dma_req[1], dmap);
+ } else {
+ dmap = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+ setup_dma_rx_request(&prtd->dma_req[0], dmap);
+ setup_dma_rx_request(&prtd->dma_req[1], dmap);
+ }
+
+ prtd->dma_req[0].dev = prtd;
+ prtd->dma_req[1].dev = prtd;
+
+ prtd->dma_chan = tegra_dma_allocate_channel(TEGRA_DMA_MODE_ONESHOT);
+ if (IS_ERR(prtd->dma_chan)) {
+ ret = PTR_ERR(prtd->dma_chan);
+ goto err;
+ }
+
+ /* Set HW params now that initialization is complete */
+ snd_soc_set_runtime_hwparams(substream, &tegra_pcm_hardware);
+
+ /* Ensure that buffer size is a multiple of period size */
+ ret = snd_pcm_hw_constraint_integer(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS);
+ if (ret < 0)
+ goto err;
+
+ return 0;
+
+err:
+ if (prtd->dma_chan) {
+ tegra_dma_free_channel(prtd->dma_chan);
+ }
+
+ kfree(prtd);
+
+ return ret;
+}
+
+static int tegra_pcm_close(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct tegra_runtime_data *prtd = runtime->private_data;
+
+ tegra_dma_free_channel(prtd->dma_chan);
+
+ kfree(prtd);
+
+ return 0;
+}
+
+static int tegra_pcm_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct tegra_runtime_data *prtd = runtime->private_data;
+
+ snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+
+ prtd->dma_req[0].size = params_period_bytes(params);
+ prtd->dma_req[1].size = prtd->dma_req[0].size;
+
+ return 0;
+}
+
+static int tegra_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+ snd_pcm_set_runtime_buffer(substream, NULL);
+
+ return 0;
+}
+
+static int tegra_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct tegra_runtime_data *prtd = runtime->private_data;
+ unsigned long flags;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ prtd->dma_pos = 0;
+ prtd->dma_pos_end = frames_to_bytes(runtime, runtime->periods * runtime->period_size);
+ prtd->period_index = 0;
+ prtd->dma_req_idx = 0;
+ /* Fall-through */
+ case SNDRV_PCM_TRIGGER_RESUME:
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ spin_lock_irqsave(&prtd->lock, flags);
+ prtd->running = 1;
+ spin_unlock_irqrestore(&prtd->lock, flags);
+ tegra_pcm_queue_dma(prtd);
+ tegra_pcm_queue_dma(prtd);
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ case SNDRV_PCM_TRIGGER_SUSPEND:
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ spin_lock_irqsave(&prtd->lock, flags);
+ prtd->running = 0;
+ spin_unlock_irqrestore(&prtd->lock, flags);
+ tegra_dma_dequeue_req(prtd->dma_chan, &prtd->dma_req[0]);
+ tegra_dma_dequeue_req(prtd->dma_chan, &prtd->dma_req[1]);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static snd_pcm_uframes_t tegra_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct tegra_runtime_data *prtd = runtime->private_data;
+
+ return prtd->period_index * runtime->period_size;
+}
+
+
+static int tegra_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 tegra_pcm_ops = {
+ .open = tegra_pcm_open,
+ .close = tegra_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = tegra_pcm_hw_params,
+ .hw_free = tegra_pcm_hw_free,
+ .trigger = tegra_pcm_trigger,
+ .pointer = tegra_pcm_pointer,
+ .mmap = tegra_pcm_mmap,
+};
+
+static int tegra_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
+{
+ struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+ struct snd_dma_buffer *buf = &substream->dma_buffer;
+ size_t size = tegra_pcm_hardware.buffer_bytes_max;
+
+ buf->area = dma_alloc_writecombine(pcm->card->dev, size,
+ &buf->addr, GFP_KERNEL);
+ if (!buf->area)
+ return -ENOMEM;
+
+ buf->dev.type = SNDRV_DMA_TYPE_DEV;
+ buf->dev.dev = pcm->card->dev;
+ buf->private_data = NULL;
+ buf->bytes = size;
+
+ return 0;
+}
+
+static void tegra_pcm_deallocate_dma_buffer(struct snd_pcm *pcm, int stream)
+{
+ struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+ struct snd_dma_buffer *buf = &substream->dma_buffer;
+
+ if (!buf->area)
+ return;
+
+ dma_free_writecombine(pcm->card->dev, buf->bytes,
+ buf->area, buf->addr);
+ buf->area = NULL;
+}
+
+static u64 tegra_dma_mask = DMA_BIT_MASK(32);
+
+static int tegra_pcm_new(struct snd_card *card,
+ struct snd_soc_dai *dai, struct snd_pcm *pcm)
+{
+ int ret = 0;
+
+ if (!card->dev->dma_mask)
+ card->dev->dma_mask = &tegra_dma_mask;
+ if (!card->dev->coherent_dma_mask)
+ card->dev->coherent_dma_mask = 0xffffffff;
+
+ if (dai->driver->playback.channels_min) {
+ ret = tegra_pcm_preallocate_dma_buffer(pcm,
+ SNDRV_PCM_STREAM_PLAYBACK);
+ if (ret)
+ goto err;
+ }
+
+ if (dai->driver->capture.channels_min) {
+ ret = tegra_pcm_preallocate_dma_buffer(pcm,
+ SNDRV_PCM_STREAM_CAPTURE);
+ if (ret)
+ goto err_free_play;
+ }
+
+ return 0;
+
+err_free_play:
+ tegra_pcm_deallocate_dma_buffer(pcm, SNDRV_PCM_STREAM_PLAYBACK);
+err:
+ return ret;
+}
+
+static void tegra_pcm_free(struct snd_pcm *pcm)
+{
+ tegra_pcm_deallocate_dma_buffer(pcm, SNDRV_PCM_STREAM_CAPTURE);
+ tegra_pcm_deallocate_dma_buffer(pcm, SNDRV_PCM_STREAM_PLAYBACK);
+}
+
+struct snd_soc_platform_driver tegra_pcm_platform = {
+ .ops = &tegra_pcm_ops,
+ .pcm_new = tegra_pcm_new,
+ .pcm_free = tegra_pcm_free,
+};
+
+static int __devinit tegra_pcm_platform_probe(struct platform_device *pdev)
+{
+ return snd_soc_register_platform(&pdev->dev, &tegra_pcm_platform);
+}
+
+static int __devexit tegra_pcm_platform_remove(struct platform_device *pdev)
+{
+ snd_soc_unregister_platform(&pdev->dev);
+ return 0;
+}
+
+static struct platform_driver tegra_pcm_driver = {
+ .driver = {
+ .name = "tegra-pcm-audio",
+ .owner = THIS_MODULE,
+ },
+ .probe = tegra_pcm_platform_probe,
+ .remove = __devexit_p(tegra_pcm_platform_remove),
+};
+
+static int __init snd_tegra_pcm_init(void)
+{
+ return platform_driver_register(&tegra_pcm_driver);
+}
+module_init(snd_tegra_pcm_init);
+
+static void __exit snd_tegra_pcm_exit(void)
+{
+ platform_driver_unregister(&tegra_pcm_driver);
+}
+module_exit(snd_tegra_pcm_exit);
+
+MODULE_AUTHOR("Stephen Warren <swarren at nvidia.com>");
+MODULE_DESCRIPTION("Tegra PCM ASoC driver");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/tegra/tegra_pcm.h b/sound/soc/tegra/tegra_pcm.h
new file mode 100644
index 0000000..dbb9033
--- /dev/null
+++ b/sound/soc/tegra/tegra_pcm.h
@@ -0,0 +1,55 @@
+/*
+ * tegra_pcm.h - Definitions for Tegra PCM driver
+ *
+ * Author: Stephen Warren <swarren at nvidia.com>
+ * Copyright (C) 2010 - NVIDIA, Inc.
+ *
+ * Based on code copyright/by:
+ *
+ * Copyright (c) 2009-2010, NVIDIA Corporation.
+ * Scott Peterson <speterson at nvidia.com>
+ *
+ * Copyright (C) 2010 Google, Inc.
+ * Iliyan Malchev <malchev at google.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#ifndef __TEGRA_PCM_H__
+#define __TEGRA_PCM_H__
+
+#include <mach/dma.h>
+
+struct tegra_pcm_dma_params {
+ unsigned long addr;
+ unsigned long wrap;
+ unsigned long width;
+ unsigned long req_sel;
+};
+
+struct tegra_runtime_data {
+ struct snd_pcm_substream *substream;
+ spinlock_t lock;
+ int running;
+ int dma_pos;
+ int dma_pos_end;
+ int period_index;
+ int dma_req_idx;
+ struct tegra_dma_req dma_req[2];
+ struct tegra_dma_channel *dma_chan;
+};
+
+#endif
--
1.7.0.4
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