// SPDX-License-Identifier: GPL-2.0-only
/*
* Au12x0/Au1550 PSC ALSA ASoC audio support.
*
* (c) 2007-2008 MSC Vertriebsges.m.b.H.,
* Manuel Lauss <[email protected]>
*
* DMA glue for Au1x-PSC audio.
*/
#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/au1xxx_dbdma.h>
#include <asm/mach-au1x00/au1xxx_psc.h>
#include "psc.h"
/*#define PCM_DEBUG*/
#define DRV_NAME "dbdma2"
#define MSG(x...) printk(KERN_INFO "au1xpsc_pcm: " x)
#ifdef PCM_DEBUG
#define DBG MSG
#else
#define DBG(x...) do {} while (0)
#endif
struct au1xpsc_audio_dmadata {
/* DDMA control data */
unsigned int ddma_id; /* DDMA direction ID for this PSC */
u32 ddma_chan; /* DDMA context */
/* PCM context (for irq handlers) */
struct snd_pcm_substream *substream;
unsigned long curr_period; /* current segment DDMA is working on */
unsigned long q_period; /* queue period(s) */
dma_addr_t dma_area; /* address of queued DMA area */
dma_addr_t dma_area_s; /* start address of DMA area */
unsigned long pos; /* current byte position being played */
unsigned long periods; /* number of SG segments in total */
unsigned long period_bytes; /* size in bytes of one SG segment */
/* runtime data */
int msbits;
};
/*
* These settings are somewhat okay, at least on my machine audio plays
* almost skip-free. Especially the 64kB buffer seems to help a LOT.
*/
#define AU1XPSC_PERIOD_MIN_BYTES 1024
#define AU1XPSC_BUFFER_MIN_BYTES 65536
/* PCM hardware DMA capabilities - platform specific */
static const struct snd_pcm_hardware au1xpsc_pcm_hardware = {
.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
.period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES,
.period_bytes_max = 4096 * 1024 - 1,
.periods_min = 2,
.periods_max = 4096, /* 2 to as-much-as-you-like */
.buffer_bytes_max = 4096 * 1024 - 1,
.fifo_size = 16, /* fifo entries of AC97/I2S PSC */
};
static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd)
{
au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area,
cd->period_bytes, DDMA_FLAGS_IE);
/* update next-to-queue period */
++cd->q_period;
cd->dma_area += cd->period_bytes;
if (cd->q_period >= cd->periods) {
cd->q_period = 0;
cd->dma_area = cd->dma_area_s;
}
}
static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)
{
au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area,
cd->period_bytes, DDMA_FLAGS_IE);
/* update next-to-queue period */
++cd->q_period;
cd->dma_area += cd->period_bytes;
if (cd->q_period >= cd->periods) {
cd->q_period = 0;
cd->dma_area = cd->dma_area_s;
}
}
static void au1x_pcm_dmatx_cb(int irq, void *dev_id)
{
struct au1xpsc_audio_dmadata *cd = dev_id;
cd->pos += cd->period_bytes;
if (++cd->curr_period >= cd->periods) {
cd->pos = 0;
cd->curr_period = 0;
}
snd_pcm_period_elapsed(cd->substream);
au1x_pcm_queue_tx(cd);
}
static void au1x_pcm_dmarx_cb(int irq, void *dev_id)
{
struct au1xpsc_audio_dmadata *cd = dev_id;
cd->pos += cd->period_bytes;
if (++cd->curr_period >= cd->periods) {
cd->pos = 0;
cd->curr_period = 0;
}
snd_pcm_period_elapsed(cd->substream);
au1x_pcm_queue_rx(cd);
}
static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)
{
if (pcd->ddma_chan) {
au1xxx_dbdma_stop(pcd->ddma_chan);
au1xxx_dbdma_reset(pcd->ddma_chan);
au1xxx_dbdma_chan_free(pcd->ddma_chan);
pcd->ddma_chan = 0;
pcd->msbits = 0;
}
}
/* in case of missing DMA ring or changed TX-source / RX-dest bit widths,
* allocate (or reallocate) a 2-descriptor DMA ring with bit depth according
* to ALSA-supplied sample depth. This is due to limitations in the dbdma api
* (cannot adjust source/dest widths of already allocated descriptor ring).
*/
static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,
int stype, int msbits)
{
/* DMA only in 8/16/32 bit widths */
if (msbits == 24)
msbits = 32;
/* check current config: correct bits and descriptors allocated? */
if ((pcd->ddma_chan) && (msbits == pcd->msbits))
goto out; /* all ok! */
au1x_pcm_dbdma_free(pcd);
if (stype == SNDRV_PCM_STREAM_CAPTURE)
pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,
DSCR_CMD0_ALWAYS,
au1x_pcm_dmarx_cb, (void *)pcd);
else
pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,
pcd->ddma_id,
au1x_pcm_dmatx_cb, (void *)pcd);
if (!pcd->ddma_chan)
return -ENOMEM;
au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);
au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);
pcd->msbits = msbits;
au1xxx_dbdma_stop(pcd->ddma_chan);
au1xxx_dbdma_reset(pcd->ddma_chan);
out:
return 0;
}
static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss,
struct snd_soc_component *component)
{
struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component);
return &pcd[ss->stream];
}
static int au1xpsc_pcm_hw_params(struct snd_soc_component *component,
struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct au1xpsc_audio_dmadata *pcd;
int stype, ret;
stype = substream->stream;
pcd = to_dmadata(substream, component);
DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu "
"runtime->min_align %lu\n",
(unsigned long)runtime->dma_area,
(unsigned long)runtime->dma_addr, runtime->dma_bytes,
runtime->min_align);
DBG("bits %d frags %d frag_bytes %d is_rx %d\n", params->msbits,
params_periods(params), params_period_bytes(params), stype);
ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);
if (ret) {
MSG("DDMA channel (re)alloc failed!\n");
goto out;
}
pcd->substream = substream;
pcd->period_bytes = params_period_bytes(params);
pcd->periods = params_periods(params);
pcd->dma_area_s = pcd->dma_area = runtime->dma_addr;
pcd->q_period = 0;
pcd->curr_period = 0;
pcd->pos = 0;
ret = 0;
out:
return ret;
}
static int au1xpsc_pcm_prepare(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
au1xxx_dbdma_reset(pcd->ddma_chan);
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
au1x_pcm_queue_rx(pcd);
au1x_pcm_queue_rx(pcd);
} else {
au1x_pcm_queue_tx(pcd);
au1x_pcm_queue_tx(pcd);
}
return 0;
}
static int au1xpsc_pcm_trigger(struct snd_soc_component *component,
struct snd_pcm_substream *substream, int cmd)
{
u32 c = to_dmadata(substream, component)->ddma_chan;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
au1xxx_dbdma_start(c);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
au1xxx_dbdma_stop(c);
break;
default:
return -EINVAL;
}
return 0;
}
static snd_pcm_uframes_t
au1xpsc_pcm_pointer(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
return bytes_to_frames(substream->runtime,
to_dmadata(substream, component)->pos);
}
static int au1xpsc_pcm_open(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
int stype = substream->stream, *dmaids;
dmaids = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
if (!dmaids)
return -ENODEV; /* whoa, has ordering changed? */
pcd->ddma_id = dmaids[stype];
snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);
return 0;
}
static int au1xpsc_pcm_close(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
au1x_pcm_dbdma_free(to_dmadata(substream, component));
return 0;
}
static int au1xpsc_pcm_new(struct snd_soc_component *component,
struct snd_soc_pcm_runtime *rtd)
{
struct snd_card *card = rtd->card->snd_card;
struct snd_pcm *pcm = rtd->pcm;
snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);
return 0;
}
/* au1xpsc audio platform */
static struct snd_soc_component_driver au1xpsc_soc_component = {
.name = DRV_NAME,
.open = au1xpsc_pcm_open,
.close = au1xpsc_pcm_close,
.hw_params = au1xpsc_pcm_hw_params,
.prepare = au1xpsc_pcm_prepare,
.trigger = au1xpsc_pcm_trigger,
.pointer = au1xpsc_pcm_pointer,
.pcm_construct = au1xpsc_pcm_new,
};
static int au1xpsc_pcm_drvprobe(struct platform_device *pdev)
{
struct au1xpsc_audio_dmadata *dmadata;
dmadata = devm_kcalloc(&pdev->dev,
2, sizeof(struct au1xpsc_audio_dmadata),
GFP_KERNEL);
if (!dmadata)
return -ENOMEM;
platform_set_drvdata(pdev, dmadata);
return devm_snd_soc_register_component(&pdev->dev,
&au1xpsc_soc_component, NULL, 0);
}
static struct platform_driver au1xpsc_pcm_driver = {
.driver = {
.name = "au1xpsc-pcm",
},
.probe = au1xpsc_pcm_drvprobe,
};
module_platform_driver(au1xpsc_pcm_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
MODULE_AUTHOR("Manuel Lauss");
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