// SPDX-License-Identifier: GPL-2.0-only
/*
* Au1000/Au1500/Au1100 Audio DMA support.
*
* (c) 2011 Manuel Lauss <[email protected]>
*
* copied almost verbatim from the old ALSA driver, written by
* Charles Eidsness <[email protected]>
*/
#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/mach-au1x00/au1000.h>
#include <asm/mach-au1x00/au1000_dma.h>
#include "psc.h"
#define DRV_NAME "au1x_dma"
struct pcm_period {
u32 start;
u32 relative_end; /* relative to start of buffer */
struct pcm_period *next;
};
struct audio_stream {
struct snd_pcm_substream *substream;
int dma;
struct pcm_period *buffer;
unsigned int period_size;
unsigned int periods;
};
struct alchemy_pcm_ctx {
struct audio_stream stream[2]; /* playback & capture */
};
static void au1000_release_dma_link(struct audio_stream *stream)
{
struct pcm_period *pointer;
struct pcm_period *pointer_next;
stream->period_size = 0;
stream->periods = 0;
pointer = stream->buffer;
if (!pointer)
return;
do {
pointer_next = pointer->next;
kfree(pointer);
pointer = pointer_next;
} while (pointer != stream->buffer);
stream->buffer = NULL;
}
static int au1000_setup_dma_link(struct audio_stream *stream,
unsigned int period_bytes,
unsigned int periods)
{
struct snd_pcm_substream *substream = stream->substream;
struct snd_pcm_runtime *runtime = substream->runtime;
struct pcm_period *pointer;
unsigned long dma_start;
int i;
dma_start = virt_to_phys(runtime->dma_area);
if (stream->period_size == period_bytes &&
stream->periods == periods)
return 0; /* not changed */
au1000_release_dma_link(stream);
stream->period_size = period_bytes;
stream->periods = periods;
stream->buffer = kmalloc(sizeof(struct pcm_period), GFP_KERNEL);
if (!stream->buffer)
return -ENOMEM;
pointer = stream->buffer;
for (i = 0; i < periods; i++) {
pointer->start = (u32)(dma_start + (i * period_bytes));
pointer->relative_end = (u32) (((i+1) * period_bytes) - 0x1);
if (i < periods - 1) {
pointer->next = kmalloc(sizeof(struct pcm_period),
GFP_KERNEL);
if (!pointer->next) {
au1000_release_dma_link(stream);
return -ENOMEM;
}
pointer = pointer->next;
}
}
pointer->next = stream->buffer;
return 0;
}
static void au1000_dma_stop(struct audio_stream *stream)
{
if (stream->buffer)
disable_dma(stream->dma);
}
static void au1000_dma_start(struct audio_stream *stream)
{
if (!stream->buffer)
return;
init_dma(stream->dma);
if (get_dma_active_buffer(stream->dma) == 0) {
clear_dma_done0(stream->dma);
set_dma_addr0(stream->dma, stream->buffer->start);
set_dma_count0(stream->dma, stream->period_size >> 1);
set_dma_addr1(stream->dma, stream->buffer->next->start);
set_dma_count1(stream->dma, stream->period_size >> 1);
} else {
clear_dma_done1(stream->dma);
set_dma_addr1(stream->dma, stream->buffer->start);
set_dma_count1(stream->dma, stream->period_size >> 1);
set_dma_addr0(stream->dma, stream->buffer->next->start);
set_dma_count0(stream->dma, stream->period_size >> 1);
}
enable_dma_buffers(stream->dma);
start_dma(stream->dma);
}
static irqreturn_t au1000_dma_interrupt(int irq, void *ptr)
{
struct audio_stream *stream = (struct audio_stream *)ptr;
struct snd_pcm_substream *substream = stream->substream;
switch (get_dma_buffer_done(stream->dma)) {
case DMA_D0:
stream->buffer = stream->buffer->next;
clear_dma_done0(stream->dma);
set_dma_addr0(stream->dma, stream->buffer->next->start);
set_dma_count0(stream->dma, stream->period_size >> 1);
enable_dma_buffer0(stream->dma);
break;
case DMA_D1:
stream->buffer = stream->buffer->next;
clear_dma_done1(stream->dma);
set_dma_addr1(stream->dma, stream->buffer->next->start);
set_dma_count1(stream->dma, stream->period_size >> 1);
enable_dma_buffer1(stream->dma);
break;
case (DMA_D0 | DMA_D1):
pr_debug("DMA %d missed interrupt.\n", stream->dma);
au1000_dma_stop(stream);
au1000_dma_start(stream);
break;
case (~DMA_D0 & ~DMA_D1):
pr_debug("DMA %d empty irq.\n", stream->dma);
}
snd_pcm_period_elapsed(substream);
return IRQ_HANDLED;
}
static const struct snd_pcm_hardware alchemy_pcm_hardware = {
.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
.period_bytes_min = 1024,
.period_bytes_max = 16 * 1024 - 1,
.periods_min = 4,
.periods_max = 255,
.buffer_bytes_max = 128 * 1024,
.fifo_size = 16,
};
static inline struct alchemy_pcm_ctx *ss_to_ctx(struct snd_pcm_substream *ss,
struct snd_soc_component *component)
{
return snd_soc_component_get_drvdata(component);
}
static inline struct audio_stream *ss_to_as(struct snd_pcm_substream *ss,
struct snd_soc_component *component)
{
struct alchemy_pcm_ctx *ctx = ss_to_ctx(ss, component);
return &(ctx->stream[ss->stream]);
}
static int alchemy_pcm_open(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream, component);
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
int *dmaids, s = substream->stream;
char *name;
dmaids = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
if (!dmaids)
return -ENODEV; /* whoa, has ordering changed? */
/* DMA setup */
name = (s == SNDRV_PCM_STREAM_PLAYBACK) ? "audio-tx" : "audio-rx";
ctx->stream[s].dma = request_au1000_dma(dmaids[s], name,
au1000_dma_interrupt, 0,
&ctx->stream[s]);
set_dma_mode(ctx->stream[s].dma,
get_dma_mode(ctx->stream[s].dma) & ~DMA_NC);
ctx->stream[s].substream = substream;
ctx->stream[s].buffer = NULL;
snd_soc_set_runtime_hwparams(substream, &alchemy_pcm_hardware);
return 0;
}
static int alchemy_pcm_close(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream, component);
int stype = substream->stream;
ctx->stream[stype].substream = NULL;
free_au1000_dma(ctx->stream[stype].dma);
return 0;
}
static int alchemy_pcm_hw_params(struct snd_soc_component *component,
struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
struct audio_stream *stream = ss_to_as(substream, component);
return au1000_setup_dma_link(stream,
params_period_bytes(hw_params),
params_periods(hw_params));
}
static int alchemy_pcm_hw_free(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct audio_stream *stream = ss_to_as(substream, component);
au1000_release_dma_link(stream);
return 0;
}
static int alchemy_pcm_trigger(struct snd_soc_component *component,
struct snd_pcm_substream *substream, int cmd)
{
struct audio_stream *stream = ss_to_as(substream, component);
int err = 0;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
au1000_dma_start(stream);
break;
case SNDRV_PCM_TRIGGER_STOP:
au1000_dma_stop(stream);
break;
default:
err = -EINVAL;
break;
}
return err;
}
static snd_pcm_uframes_t alchemy_pcm_pointer(struct snd_soc_component *component,
struct snd_pcm_substream *ss)
{
struct audio_stream *stream = ss_to_as(ss, component);
long location;
location = get_dma_residue(stream->dma);
location = stream->buffer->relative_end - location;
if (location == -1)
location = 0;
return bytes_to_frames(ss->runtime, location);
}
static int alchemy_pcm_new(struct snd_soc_component *component,
struct snd_soc_pcm_runtime *rtd)
{
struct snd_pcm *pcm = rtd->pcm;
snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
NULL, 65536, (4096 * 1024) - 1);
return 0;
}
static struct snd_soc_component_driver alchemy_pcm_soc_component = {
.name = DRV_NAME,
.open = alchemy_pcm_open,
.close = alchemy_pcm_close,
.hw_params = alchemy_pcm_hw_params,
.hw_free = alchemy_pcm_hw_free,
.trigger = alchemy_pcm_trigger,
.pointer = alchemy_pcm_pointer,
.pcm_construct = alchemy_pcm_new,
};
static int alchemy_pcm_drvprobe(struct platform_device *pdev)
{
struct alchemy_pcm_ctx *ctx;
ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
platform_set_drvdata(pdev, ctx);
return devm_snd_soc_register_component(&pdev->dev,
&alchemy_pcm_soc_component, NULL, 0);
}
static struct platform_driver alchemy_pcmdma_driver = {
.driver = {
.name = "alchemy-pcm-dma",
},
.probe = alchemy_pcm_drvprobe,
};
module_platform_driver(alchemy_pcmdma_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Au1000/Au1500/Au1100 Audio DMA driver");
MODULE_AUTHOR("Manuel Lauss");
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