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 --- include/sound/spear_dma.h | 35 +++++++ sound/soc/spear/spear_pcm.c | 214 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 249 insertions(+), 0 deletions(-) create mode 100644 include/sound/spear_dma.h create mode 100644 sound/soc/spear/spear_pcm.c
diff --git a/include/sound/spear_dma.h b/include/sound/spear_dma.h new file mode 100644 index 0000000..1b365bf --- /dev/null +++ b/include/sound/spear_dma.h @@ -0,0 +1,35 @@ +/* +* linux/spear_dma.h +* +* Copyright (ST) 2012 Rajeev Kumar (rajeev-dlh.kumar@st.com) +* +* 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. +* +* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +* +*/ + +#ifndef SPEAR_DMA_H +#define SPEAR_DMA_H + +#include <linux/dmaengine.h> + +struct spear_dma_data { + void *data; + dma_addr_t addr; + u32 max_burst; + enum dma_slave_buswidth addr_width; + bool (*filter)(struct dma_chan *chan, void *slave); +}; + +#endif /* SPEAR_DMA_H */ diff --git a/sound/soc/spear/spear_pcm.c b/sound/soc/spear/spear_pcm.c new file mode 100644 index 0000000..97c2cac --- /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 Kumarrajeev-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");