satip-axe/kernel/sound/soc/imx/mx1_mx2-pcm.c
2015-03-26 17:24:57 +01:00

489 lines
12 KiB
C

/*
* mx1_mx2-pcm.c -- ALSA SoC interface for Freescale i.MX1x, i.MX2x CPUs
*
* Copyright 2009 Vista Silicon S.L.
* Author: Javier Martin
* javier.martin@vista-silicon.com
*
* Based on mxc-pcm.c by Liam Girdwood.
*
* 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.
*
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <asm/dma.h>
#include <mach/hardware.h>
#include <mach/dma-mx1-mx2.h>
#include "mx1_mx2-pcm.h"
static const struct snd_pcm_hardware mx1_mx2_pcm_hardware = {
.info = (SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID),
.formats = SNDRV_PCM_FMTBIT_S16_LE,
.buffer_bytes_max = 32 * 1024,
.period_bytes_min = 64,
.period_bytes_max = 8 * 1024,
.periods_min = 2,
.periods_max = 255,
.fifo_size = 0,
};
struct mx1_mx2_runtime_data {
int dma_ch;
int active;
unsigned int period;
unsigned int periods;
int tx_spin;
spinlock_t dma_lock;
struct mx1_mx2_pcm_dma_params *dma_params;
};
/**
* This function stops the current dma transfer for playback
* and clears the dma pointers.
*
* @param substream pointer to the structure of the current stream.
*
*/
static int audio_stop_dma(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd = runtime->private_data;
unsigned long flags;
spin_lock_irqsave(&prtd->dma_lock, flags);
pr_debug("%s\n", __func__);
prtd->active = 0;
prtd->period = 0;
prtd->periods = 0;
/* this stops the dma channel and clears the buffer ptrs */
imx_dma_disable(prtd->dma_ch);
spin_unlock_irqrestore(&prtd->dma_lock, flags);
return 0;
}
/**
* This function is called whenever a new audio block needs to be
* transferred to the codec. The function receives the address and the size
* of the new block and start a new DMA transfer.
*
* @param substream pointer to the structure of the current stream.
*
*/
static int dma_new_period(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd = runtime->private_data;
unsigned int dma_size;
unsigned int offset;
int ret = 0;
dma_addr_t mem_addr;
unsigned int dev_addr;
if (prtd->active) {
dma_size = frames_to_bytes(runtime, runtime->period_size);
offset = dma_size * prtd->period;
pr_debug("%s: period (%d) out of (%d)\n", __func__,
prtd->period,
runtime->periods);
pr_debug("period_size %d frames\n offset %d bytes\n",
(unsigned int)runtime->period_size,
offset);
pr_debug("dma_size %d bytes\n", dma_size);
snd_BUG_ON(dma_size > mx1_mx2_pcm_hardware.period_bytes_max);
mem_addr = (dma_addr_t)(runtime->dma_addr + offset);
dev_addr = prtd->dma_params->per_address;
pr_debug("%s: mem_addr is %x\n dev_addr is %x\n",
__func__, mem_addr, dev_addr);
ret = imx_dma_setup_single(prtd->dma_ch, mem_addr,
dma_size, dev_addr,
prtd->dma_params->transfer_type);
if (ret < 0) {
printk(KERN_ERR "Error %d configuring DMA\n", ret);
return ret;
}
imx_dma_enable(prtd->dma_ch);
pr_debug("%s: transfer enabled\nmem_addr = %x\n",
__func__, (unsigned int) mem_addr);
pr_debug("dev_addr = %x\ndma_size = %d\n",
(unsigned int) dev_addr, dma_size);
prtd->tx_spin = 1; /* FGA little trick to retrieve DMA pos */
prtd->period++;
prtd->period %= runtime->periods;
}
return ret;
}
/**
* This is a callback which will be called
* when a TX transfer finishes. The call occurs
* in interrupt context.
*
* @param dat pointer to the structure of the current stream.
*
*/
static void audio_dma_irq(int channel, void *data)
{
struct snd_pcm_substream *substream;
struct snd_pcm_runtime *runtime;
struct mx1_mx2_runtime_data *prtd;
unsigned int dma_size;
unsigned int previous_period;
unsigned int offset;
substream = data;
runtime = substream->runtime;
prtd = runtime->private_data;
previous_period = prtd->periods;
dma_size = frames_to_bytes(runtime, runtime->period_size);
offset = dma_size * previous_period;
prtd->tx_spin = 0;
prtd->periods++;
prtd->periods %= runtime->periods;
pr_debug("%s: irq per %d offset %x\n", __func__, prtd->periods, offset);
/*
* If we are getting a callback for an active stream then we inform
* the PCM middle layer we've finished a period
*/
if (prtd->active)
snd_pcm_period_elapsed(substream);
/*
* Trig next DMA transfer
*/
dma_new_period(substream);
}
/**
* This function configures the hardware to allow audio
* playback operations. It is called by ALSA framework.
*
* @param substream pointer to the structure of the current stream.
*
* @return 0 on success, -1 otherwise.
*/
static int
snd_mx1_mx2_prepare(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd = runtime->private_data;
prtd->period = 0;
prtd->periods = 0;
return 0;
}
static int mx1_mx2_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
int ret;
ret = snd_pcm_lib_malloc_pages(substream,
params_buffer_bytes(hw_params));
if (ret < 0) {
printk(KERN_ERR "%s: Error %d failed to malloc pcm pages \n",
__func__, ret);
return ret;
}
pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_addr 0x(%x)\n",
__func__, (unsigned int)runtime->dma_addr);
pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_area 0x(%x)\n",
__func__, (unsigned int)runtime->dma_area);
pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_bytes 0x(%x)\n",
__func__, (unsigned int)runtime->dma_bytes);
return ret;
}
static int mx1_mx2_pcm_hw_free(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd = runtime->private_data;
imx_dma_free(prtd->dma_ch);
snd_pcm_lib_free_pages(substream);
return 0;
}
static int mx1_mx2_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct mx1_mx2_runtime_data *prtd = substream->runtime->private_data;
int ret = 0;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
prtd->tx_spin = 0;
/* requested stream startup */
prtd->active = 1;
pr_debug("%s: starting dma_new_period\n", __func__);
ret = dma_new_period(substream);
break;
case SNDRV_PCM_TRIGGER_STOP:
/* requested stream shutdown */
pr_debug("%s: stopping dma transfer\n", __func__);
ret = audio_stop_dma(substream);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static snd_pcm_uframes_t
mx1_mx2_pcm_pointer(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd = runtime->private_data;
unsigned int offset = 0;
/* tx_spin value is used here to check if a transfer is active */
if (prtd->tx_spin) {
offset = (runtime->period_size * (prtd->periods)) +
(runtime->period_size >> 1);
if (offset >= runtime->buffer_size)
offset = runtime->period_size >> 1;
} else {
offset = (runtime->period_size * (prtd->periods));
if (offset >= runtime->buffer_size)
offset = 0;
}
pr_debug("%s: pointer offset %x\n", __func__, offset);
return offset;
}
static int mx1_mx2_pcm_open(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct mx1_mx2_pcm_dma_params *dma_data = rtd->dai->cpu_dai->dma_data;
int ret;
snd_soc_set_runtime_hwparams(substream, &mx1_mx2_pcm_hardware);
ret = snd_pcm_hw_constraint_integer(runtime,
SNDRV_PCM_HW_PARAM_PERIODS);
if (ret < 0)
return ret;
prtd = kzalloc(sizeof(struct mx1_mx2_runtime_data), GFP_KERNEL);
if (prtd == NULL) {
ret = -ENOMEM;
goto out;
}
runtime->private_data = prtd;
if (!dma_data)
return -ENODEV;
prtd->dma_params = dma_data;
pr_debug("%s: Requesting dma channel (%s)\n", __func__,
prtd->dma_params->name);
prtd->dma_ch = imx_dma_request_by_prio(prtd->dma_params->name,
DMA_PRIO_HIGH);
if (prtd->dma_ch < 0) {
printk(KERN_ERR "Error %d requesting dma channel\n", ret);
return ret;
}
imx_dma_config_burstlen(prtd->dma_ch,
prtd->dma_params->watermark_level);
ret = imx_dma_config_channel(prtd->dma_ch,
prtd->dma_params->per_config,
prtd->dma_params->mem_config,
prtd->dma_params->event_id, 0);
if (ret) {
pr_debug(KERN_ERR "Error %d configuring dma channel %d\n",
ret, prtd->dma_ch);
return ret;
}
pr_debug("%s: Setting tx dma callback function\n", __func__);
ret = imx_dma_setup_handlers(prtd->dma_ch,
audio_dma_irq, NULL,
(void *)substream);
if (ret < 0) {
printk(KERN_ERR "Error %d setting dma callback function\n", ret);
return ret;
}
return 0;
out:
return ret;
}
static int mx1_mx2_pcm_close(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mx1_mx2_runtime_data *prtd = runtime->private_data;
kfree(prtd);
return 0;
}
static int mx1_mx2_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 mx1_mx2_pcm_ops = {
.open = mx1_mx2_pcm_open,
.close = mx1_mx2_pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = mx1_mx2_pcm_hw_params,
.hw_free = mx1_mx2_pcm_hw_free,
.prepare = snd_mx1_mx2_prepare,
.trigger = mx1_mx2_pcm_trigger,
.pointer = mx1_mx2_pcm_pointer,
.mmap = mx1_mx2_pcm_mmap,
};
static u64 mx1_mx2_pcm_dmamask = 0xffffffff;
static int mx1_mx2_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 = mx1_mx2_pcm_hardware.buffer_bytes_max;
buf->dev.type = SNDRV_DMA_TYPE_DEV;
buf->dev.dev = pcm->card->dev;
buf->private_data = NULL;
/* Reserve uncached-buffered memory area for DMA */
buf->area = dma_alloc_writecombine(pcm->card->dev, size,
&buf->addr, GFP_KERNEL);
pr_debug("%s: preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
__func__, (void *) buf->area, (void *) buf->addr, size);
if (!buf->area)
return -ENOMEM;
buf->bytes = size;
return 0;
}
static void mx1_mx2_pcm_free_dma_buffers(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->area)
continue;
dma_free_writecombine(pcm->card->dev, buf->bytes,
buf->area, buf->addr);
buf->area = NULL;
}
}
static int mx1_mx2_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 = &mx1_mx2_pcm_dmamask;
if (!card->dev->coherent_dma_mask)
card->dev->coherent_dma_mask = 0xffffffff;
if (dai->playback.channels_min) {
ret = mx1_mx2_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
pr_debug("%s: preallocate playback buffer\n", __func__);
if (ret)
goto out;
}
if (dai->capture.channels_min) {
ret = mx1_mx2_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_CAPTURE);
pr_debug("%s: preallocate capture buffer\n", __func__);
if (ret)
goto out;
}
out:
return ret;
}
struct snd_soc_platform mx1_mx2_soc_platform = {
.name = "mx1_mx2-audio",
.pcm_ops = &mx1_mx2_pcm_ops,
.pcm_new = mx1_mx2_pcm_new,
.pcm_free = mx1_mx2_pcm_free_dma_buffers,
};
EXPORT_SYMBOL_GPL(mx1_mx2_soc_platform);
static int __init mx1_mx2_soc_platform_init(void)
{
return snd_soc_register_platform(&mx1_mx2_soc_platform);
}
module_init(mx1_mx2_soc_platform_init);
static void __exit mx1_mx2_soc_platform_exit(void)
{
snd_soc_unregister_platform(&mx1_mx2_soc_platform);
}
module_exit(mx1_mx2_soc_platform_exit);
MODULE_AUTHOR("Javier Martin, javier.martin@vista-silicon.com");
MODULE_DESCRIPTION("Freescale i.MX2x, i.MX1x PCM DMA module");
MODULE_LICENSE("GPL");