linux/sound/soc/kirkwood/kirkwood-i2s.c
Russell King 982b604bc5 ASoC: kirkwood-i2s: fix DMA underruns
Stress testing the driver with multiple start/stop events causes
kirkwood-dma to report underrun errors (which used to cause the kernel
to lock up solidly).  This is because kirkwood-i2s is not respecting
the restrictions imposed on clearing the 'pause' bit.  Follow what the
spec says; the busy bit must be read as being clear twice before the
pause bit can be released.  This solves the underruns.

However, it has been noticed that the busy bit occasionally does not
clear itself, hence the waiting is bounded to 5ms maximum to avoid a
new reason for the kernel to lockup.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-11-21 10:38:39 +09:00

520 lines
13 KiB
C

/*
* kirkwood-i2s.c
*
* (c) 2010 Arnaud Patard <apatard@mandriva.com>
* (c) 2010 Arnaud Patard <arnaud.patard@rtp-net.org>
*
* 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.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/mbus.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <linux/platform_data/asoc-kirkwood.h>
#include "kirkwood.h"
#define DRV_NAME "kirkwood-i2s"
#define KIRKWOOD_I2S_RATES \
(SNDRV_PCM_RATE_44100 | \
SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
#define KIRKWOOD_I2S_FORMATS \
(SNDRV_PCM_FMTBIT_S16_LE | \
SNDRV_PCM_FMTBIT_S24_LE | \
SNDRV_PCM_FMTBIT_S32_LE)
static int kirkwood_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
unsigned int fmt)
{
struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(cpu_dai);
unsigned long mask;
unsigned long value;
switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
case SND_SOC_DAIFMT_RIGHT_J:
mask = KIRKWOOD_I2S_CTL_RJ;
break;
case SND_SOC_DAIFMT_LEFT_J:
mask = KIRKWOOD_I2S_CTL_LJ;
break;
case SND_SOC_DAIFMT_I2S:
mask = KIRKWOOD_I2S_CTL_I2S;
break;
default:
return -EINVAL;
}
/*
* Set same format for playback and record
* This avoids some troubles.
*/
value = readl(priv->io+KIRKWOOD_I2S_PLAYCTL);
value &= ~KIRKWOOD_I2S_CTL_JUST_MASK;
value |= mask;
writel(value, priv->io+KIRKWOOD_I2S_PLAYCTL);
value = readl(priv->io+KIRKWOOD_I2S_RECCTL);
value &= ~KIRKWOOD_I2S_CTL_JUST_MASK;
value |= mask;
writel(value, priv->io+KIRKWOOD_I2S_RECCTL);
return 0;
}
static inline void kirkwood_set_dco(void __iomem *io, unsigned long rate)
{
unsigned long value;
value = KIRKWOOD_DCO_CTL_OFFSET_0;
switch (rate) {
default:
case 44100:
value |= KIRKWOOD_DCO_CTL_FREQ_11;
break;
case 48000:
value |= KIRKWOOD_DCO_CTL_FREQ_12;
break;
case 96000:
value |= KIRKWOOD_DCO_CTL_FREQ_24;
break;
}
writel(value, io + KIRKWOOD_DCO_CTL);
/* wait for dco locked */
do {
cpu_relax();
value = readl(io + KIRKWOOD_DCO_SPCR_STATUS);
value &= KIRKWOOD_DCO_SPCR_STATUS_DCO_LOCK;
} while (value == 0);
}
static int kirkwood_i2s_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(dai);
snd_soc_dai_set_dma_data(dai, substream, priv);
return 0;
}
static int kirkwood_i2s_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
{
struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(dai);
unsigned int i2s_reg, reg;
unsigned long i2s_value, value;
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
i2s_reg = KIRKWOOD_I2S_PLAYCTL;
reg = KIRKWOOD_PLAYCTL;
} else {
i2s_reg = KIRKWOOD_I2S_RECCTL;
reg = KIRKWOOD_RECCTL;
}
/* set dco conf */
kirkwood_set_dco(priv->io, params_rate(params));
i2s_value = readl(priv->io+i2s_reg);
i2s_value &= ~KIRKWOOD_I2S_CTL_SIZE_MASK;
value = readl(priv->io+reg);
value &= ~KIRKWOOD_PLAYCTL_SIZE_MASK;
/*
* Size settings in play/rec i2s control regs and play/rec control
* regs must be the same.
*/
switch (params_format(params)) {
case SNDRV_PCM_FORMAT_S16_LE:
i2s_value |= KIRKWOOD_I2S_CTL_SIZE_16;
value |= KIRKWOOD_PLAYCTL_SIZE_16_C;
break;
/*
* doesn't work... S20_3LE != kirkwood 20bit format ?
*
case SNDRV_PCM_FORMAT_S20_3LE:
i2s_value |= KIRKWOOD_I2S_CTL_SIZE_20;
value |= KIRKWOOD_PLAYCTL_SIZE_20;
break;
*/
case SNDRV_PCM_FORMAT_S24_LE:
i2s_value |= KIRKWOOD_I2S_CTL_SIZE_24;
value |= KIRKWOOD_PLAYCTL_SIZE_24;
break;
case SNDRV_PCM_FORMAT_S32_LE:
i2s_value |= KIRKWOOD_I2S_CTL_SIZE_32;
value |= KIRKWOOD_PLAYCTL_SIZE_32;
break;
default:
return -EINVAL;
}
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
value &= ~KIRKWOOD_PLAYCTL_MONO_MASK;
if (params_channels(params) == 1)
value |= KIRKWOOD_PLAYCTL_MONO_BOTH;
else
value |= KIRKWOOD_PLAYCTL_MONO_OFF;
}
writel(i2s_value, priv->io+i2s_reg);
writel(value, priv->io+reg);
return 0;
}
static int kirkwood_i2s_play_trigger(struct snd_pcm_substream *substream,
int cmd, struct snd_soc_dai *dai)
{
struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(dai);
uint32_t ctl, value;
ctl = readl(priv->io + KIRKWOOD_PLAYCTL);
if (ctl & KIRKWOOD_PLAYCTL_PAUSE) {
unsigned timeout = 5000;
/*
* The Armada510 spec says that if we enter pause mode, the
* busy bit must be read back as clear _twice_. Make sure
* we respect that otherwise we get DMA underruns.
*/
do {
value = ctl;
ctl = readl(priv->io + KIRKWOOD_PLAYCTL);
if (!((ctl | value) & KIRKWOOD_PLAYCTL_PLAY_BUSY))
break;
udelay(1);
} while (timeout--);
if ((ctl | value) & KIRKWOOD_PLAYCTL_PLAY_BUSY)
dev_notice(dai->dev, "timed out waiting for busy to deassert: %08x\n",
ctl);
}
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
/* stop audio, enable interrupts */
ctl |= KIRKWOOD_PLAYCTL_PAUSE;
writel(ctl, priv->io + KIRKWOOD_PLAYCTL);
value = readl(priv->io + KIRKWOOD_INT_MASK);
value |= KIRKWOOD_INT_CAUSE_PLAY_BYTES;
writel(value, priv->io + KIRKWOOD_INT_MASK);
/* configure audio & enable i2s playback */
ctl &= ~KIRKWOOD_PLAYCTL_BURST_MASK;
ctl &= ~(KIRKWOOD_PLAYCTL_PAUSE | KIRKWOOD_PLAYCTL_I2S_MUTE
| KIRKWOOD_PLAYCTL_SPDIF_EN);
if (priv->burst == 32)
ctl |= KIRKWOOD_PLAYCTL_BURST_32;
else
ctl |= KIRKWOOD_PLAYCTL_BURST_128;
ctl |= KIRKWOOD_PLAYCTL_I2S_EN;
writel(ctl, priv->io + KIRKWOOD_PLAYCTL);
break;
case SNDRV_PCM_TRIGGER_STOP:
/* stop audio, disable interrupts */
ctl |= KIRKWOOD_PLAYCTL_PAUSE | KIRKWOOD_PLAYCTL_I2S_MUTE;
writel(ctl, priv->io + KIRKWOOD_PLAYCTL);
value = readl(priv->io + KIRKWOOD_INT_MASK);
value &= ~KIRKWOOD_INT_CAUSE_PLAY_BYTES;
writel(value, priv->io + KIRKWOOD_INT_MASK);
/* disable all playbacks */
ctl &= ~(KIRKWOOD_PLAYCTL_I2S_EN | KIRKWOOD_PLAYCTL_SPDIF_EN);
writel(ctl, priv->io + KIRKWOOD_PLAYCTL);
break;
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
case SNDRV_PCM_TRIGGER_SUSPEND:
ctl |= KIRKWOOD_PLAYCTL_PAUSE | KIRKWOOD_PLAYCTL_I2S_MUTE;
writel(ctl, priv->io + KIRKWOOD_PLAYCTL);
break;
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
ctl &= ~(KIRKWOOD_PLAYCTL_PAUSE | KIRKWOOD_PLAYCTL_I2S_MUTE);
writel(ctl, priv->io + KIRKWOOD_PLAYCTL);
break;
default:
return -EINVAL;
}
return 0;
}
static int kirkwood_i2s_rec_trigger(struct snd_pcm_substream *substream,
int cmd, struct snd_soc_dai *dai)
{
struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(dai);
unsigned long value;
value = readl(priv->io + KIRKWOOD_RECCTL);
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
/* stop audio, enable interrupts */
value = readl(priv->io + KIRKWOOD_RECCTL);
value |= KIRKWOOD_RECCTL_PAUSE;
writel(value, priv->io + KIRKWOOD_RECCTL);
value = readl(priv->io + KIRKWOOD_INT_MASK);
value |= KIRKWOOD_INT_CAUSE_REC_BYTES;
writel(value, priv->io + KIRKWOOD_INT_MASK);
/* configure audio & enable i2s record */
value = readl(priv->io + KIRKWOOD_RECCTL);
value &= ~KIRKWOOD_RECCTL_BURST_MASK;
value &= ~KIRKWOOD_RECCTL_MONO;
value &= ~(KIRKWOOD_RECCTL_PAUSE | KIRKWOOD_RECCTL_MUTE
| KIRKWOOD_RECCTL_SPDIF_EN);
if (priv->burst == 32)
value |= KIRKWOOD_RECCTL_BURST_32;
else
value |= KIRKWOOD_RECCTL_BURST_128;
value |= KIRKWOOD_RECCTL_I2S_EN;
writel(value, priv->io + KIRKWOOD_RECCTL);
break;
case SNDRV_PCM_TRIGGER_STOP:
/* stop audio, disable interrupts */
value = readl(priv->io + KIRKWOOD_RECCTL);
value |= KIRKWOOD_RECCTL_PAUSE | KIRKWOOD_RECCTL_MUTE;
writel(value, priv->io + KIRKWOOD_RECCTL);
value = readl(priv->io + KIRKWOOD_INT_MASK);
value &= ~KIRKWOOD_INT_CAUSE_REC_BYTES;
writel(value, priv->io + KIRKWOOD_INT_MASK);
/* disable all records */
value = readl(priv->io + KIRKWOOD_RECCTL);
value &= ~(KIRKWOOD_RECCTL_I2S_EN | KIRKWOOD_RECCTL_SPDIF_EN);
writel(value, priv->io + KIRKWOOD_RECCTL);
break;
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
case SNDRV_PCM_TRIGGER_SUSPEND:
value = readl(priv->io + KIRKWOOD_RECCTL);
value |= KIRKWOOD_RECCTL_PAUSE | KIRKWOOD_RECCTL_MUTE;
writel(value, priv->io + KIRKWOOD_RECCTL);
break;
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
value = readl(priv->io + KIRKWOOD_RECCTL);
value &= ~(KIRKWOOD_RECCTL_PAUSE | KIRKWOOD_RECCTL_MUTE);
writel(value, priv->io + KIRKWOOD_RECCTL);
break;
default:
return -EINVAL;
}
return 0;
}
static int kirkwood_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)
{
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
return kirkwood_i2s_play_trigger(substream, cmd, dai);
else
return kirkwood_i2s_rec_trigger(substream, cmd, dai);
return 0;
}
static int kirkwood_i2s_probe(struct snd_soc_dai *dai)
{
struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(dai);
unsigned long value;
unsigned int reg_data;
/* put system in a "safe" state : */
/* disable audio interrupts */
writel(0xffffffff, priv->io + KIRKWOOD_INT_CAUSE);
writel(0, priv->io + KIRKWOOD_INT_MASK);
reg_data = readl(priv->io + 0x1200);
reg_data &= (~(0x333FF8));
reg_data |= 0x111D18;
writel(reg_data, priv->io + 0x1200);
msleep(500);
reg_data = readl(priv->io + 0x1200);
reg_data &= (~(0x333FF8));
reg_data |= 0x111D18;
writel(reg_data, priv->io + 0x1200);
/* disable playback/record */
value = readl(priv->io + KIRKWOOD_PLAYCTL);
value &= ~(KIRKWOOD_PLAYCTL_I2S_EN|KIRKWOOD_PLAYCTL_SPDIF_EN);
writel(value, priv->io + KIRKWOOD_PLAYCTL);
value = readl(priv->io + KIRKWOOD_RECCTL);
value &= ~(KIRKWOOD_RECCTL_I2S_EN | KIRKWOOD_RECCTL_SPDIF_EN);
writel(value, priv->io + KIRKWOOD_RECCTL);
return 0;
}
static int kirkwood_i2s_remove(struct snd_soc_dai *dai)
{
return 0;
}
static const struct snd_soc_dai_ops kirkwood_i2s_dai_ops = {
.startup = kirkwood_i2s_startup,
.trigger = kirkwood_i2s_trigger,
.hw_params = kirkwood_i2s_hw_params,
.set_fmt = kirkwood_i2s_set_fmt,
};
static struct snd_soc_dai_driver kirkwood_i2s_dai = {
.probe = kirkwood_i2s_probe,
.remove = kirkwood_i2s_remove,
.playback = {
.channels_min = 1,
.channels_max = 2,
.rates = KIRKWOOD_I2S_RATES,
.formats = KIRKWOOD_I2S_FORMATS,},
.capture = {
.channels_min = 1,
.channels_max = 2,
.rates = KIRKWOOD_I2S_RATES,
.formats = KIRKWOOD_I2S_FORMATS,},
.ops = &kirkwood_i2s_dai_ops,
};
static __devinit int kirkwood_i2s_dev_probe(struct platform_device *pdev)
{
struct resource *mem;
struct kirkwood_asoc_platform_data *data =
pdev->dev.platform_data;
struct kirkwood_dma_data *priv;
int err;
priv = kzalloc(sizeof(struct kirkwood_dma_data), GFP_KERNEL);
if (!priv) {
dev_err(&pdev->dev, "allocation failed\n");
err = -ENOMEM;
goto error;
}
dev_set_drvdata(&pdev->dev, priv);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(&pdev->dev, "platform_get_resource failed\n");
err = -ENXIO;
goto err_alloc;
}
priv->mem = request_mem_region(mem->start, SZ_16K, DRV_NAME);
if (!priv->mem) {
dev_err(&pdev->dev, "request_mem_region failed\n");
err = -EBUSY;
goto err_alloc;
}
priv->io = ioremap(priv->mem->start, SZ_16K);
if (!priv->io) {
dev_err(&pdev->dev, "ioremap failed\n");
err = -ENOMEM;
goto err_iomem;
}
priv->irq = platform_get_irq(pdev, 0);
if (priv->irq <= 0) {
dev_err(&pdev->dev, "platform_get_irq failed\n");
err = -ENXIO;
goto err_ioremap;
}
if (!data) {
dev_err(&pdev->dev, "no platform data ?!\n");
err = -EINVAL;
goto err_ioremap;
}
priv->burst = data->burst;
priv->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(priv->clk)) {
dev_err(&pdev->dev, "no clock\n");
err = PTR_ERR(priv->clk);
goto err_ioremap;
}
clk_prepare_enable(priv->clk);
err = snd_soc_register_dai(&pdev->dev, &kirkwood_i2s_dai);
if (!err)
return 0;
dev_err(&pdev->dev, "snd_soc_register_dai failed\n");
clk_disable_unprepare(priv->clk);
clk_put(priv->clk);
err_ioremap:
iounmap(priv->io);
err_iomem:
release_mem_region(priv->mem->start, SZ_16K);
err_alloc:
kfree(priv);
error:
return err;
}
static __devexit int kirkwood_i2s_dev_remove(struct platform_device *pdev)
{
struct kirkwood_dma_data *priv = dev_get_drvdata(&pdev->dev);
snd_soc_unregister_dai(&pdev->dev);
clk_disable_unprepare(priv->clk);
clk_put(priv->clk);
iounmap(priv->io);
release_mem_region(priv->mem->start, SZ_16K);
kfree(priv);
return 0;
}
static struct platform_driver kirkwood_i2s_driver = {
.probe = kirkwood_i2s_dev_probe,
.remove = __devexit_p(kirkwood_i2s_dev_remove),
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
};
module_platform_driver(kirkwood_i2s_driver);
/* Module information */
MODULE_AUTHOR("Arnaud Patard, <arnaud.patard@rtp-net.org>");
MODULE_DESCRIPTION("Kirkwood I2S SoC Interface");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:kirkwood-i2s");