- 根目录:
- sound
- soc
- ep93xx
- ep93xx-ac97.c
/*
* ASoC driver for Cirrus Logic EP93xx AC97 controller.
*
* Copyright (c) 2010 Mika Westerberg
*
* Based on s3c-ac97 ASoC driver by Jaswinder Singh.
*
* 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/delay.h>
#include <linux/io.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/ac97_codec.h>
#include <sound/soc.h>
#include <mach/dma.h>
#include "ep93xx-pcm.h"
/*
* Per channel (1-4) registers.
*/
#define AC97CH(n) (((n) - 1) * 0x20)
#define AC97DR(n) (AC97CH(n) + 0x0000)
#define AC97RXCR(n) (AC97CH(n) + 0x0004)
#define AC97RXCR_REN BIT(0)
#define AC97RXCR_RX3 BIT(3)
#define AC97RXCR_RX4 BIT(4)
#define AC97RXCR_CM BIT(15)
#define AC97TXCR(n) (AC97CH(n) + 0x0008)
#define AC97TXCR_TEN BIT(0)
#define AC97TXCR_TX3 BIT(3)
#define AC97TXCR_TX4 BIT(4)
#define AC97TXCR_CM BIT(15)
#define AC97SR(n) (AC97CH(n) + 0x000c)
#define AC97SR_TXFE BIT(1)
#define AC97SR_TXUE BIT(6)
#define AC97RISR(n) (AC97CH(n) + 0x0010)
#define AC97ISR(n) (AC97CH(n) + 0x0014)
#define AC97IE(n) (AC97CH(n) + 0x0018)
/*
* Global AC97 controller registers.
*/
#define AC97S1DATA 0x0080
#define AC97S2DATA 0x0084
#define AC97S12DATA 0x0088
#define AC97RGIS 0x008c
#define AC97GIS 0x0090
#define AC97IM 0x0094
/*
* Common bits for RGIS, GIS and IM registers.
*/
#define AC97_SLOT2RXVALID BIT(1)
#define AC97_CODECREADY BIT(5)
#define AC97_SLOT2TXCOMPLETE BIT(6)
#define AC97EOI 0x0098
#define AC97EOI_WINT BIT(0)
#define AC97EOI_CODECREADY BIT(1)
#define AC97GCR 0x009c
#define AC97GCR_AC97IFE BIT(0)
#define AC97RESET 0x00a0
#define AC97RESET_TIMEDRESET BIT(0)
#define AC97SYNC 0x00a4
#define AC97SYNC_TIMEDSYNC BIT(0)
#define AC97_TIMEOUT msecs_to_jiffies(5)
/**
* struct ep93xx_ac97_info - EP93xx AC97 controller info structure
* @lock: mutex serializing access to the bus (slot 1 & 2 ops)
* @dev: pointer to the platform device dev structure
* @mem: physical memory resource for the registers
* @regs: mapped AC97 controller registers
* @irq: AC97 interrupt number
* @done: bus ops wait here for an interrupt
*/
struct ep93xx_ac97_info {
struct mutex lock;
struct device *dev;
struct resource *mem;
void __iomem *regs;
int irq;
struct completion done;
};
/* currently ALSA only supports a single AC97 device */
static struct ep93xx_ac97_info *ep93xx_ac97_info;
static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_out = {
.name = "ac97-pcm-out",
.dma_port = EP93XX_DMA_AAC1,
};
static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_in = {
.name = "ac97-pcm-in",
.dma_port = EP93XX_DMA_AAC1,
};
static inline unsigned ep93xx_ac97_read_reg(struct ep93xx_ac97_info *info,
unsigned reg)
{
return __raw_readl(info->regs + reg);
}
static inline void ep93xx_ac97_write_reg(struct ep93xx_ac97_info *info,
unsigned reg, unsigned val)
{
__raw_writel(val, info->regs + reg);
}
static unsigned short ep93xx_ac97_read(struct snd_ac97 *ac97,
unsigned short reg)
{
struct ep93xx_ac97_info *info = ep93xx_ac97_info;
unsigned short val;
mutex_lock(&info->lock);
ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2RXVALID);
if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) {
dev_warn(info->dev, "timeout reading register %x\n", reg);
mutex_unlock(&info->lock);
return -ETIMEDOUT;
}
val = (unsigned short)ep93xx_ac97_read_reg(info, AC97S2DATA);
mutex_unlock(&info->lock);
return val;
}
static void ep93xx_ac97_write(struct snd_ac97 *ac97,
unsigned short reg,
unsigned short val)
{
struct ep93xx_ac97_info *info = ep93xx_ac97_info;
mutex_lock(&info->lock);
/*
* Writes to the codec need to be done so that slot 2 is filled in
* before slot 1.
*/
ep93xx_ac97_write_reg(info, AC97S2DATA, val);
ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2TXCOMPLETE);
if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
dev_warn(info->dev, "timeout writing register %x\n", reg);
mutex_unlock(&info->lock);
}
static void ep93xx_ac97_warm_reset(struct snd_ac97 *ac97)
{
struct ep93xx_ac97_info *info = ep93xx_ac97_info;
mutex_lock(&info->lock);
/*
* We are assuming that before this functions gets called, the codec
* BIT_CLK is stopped by forcing the codec into powerdown mode. We can
* control the SYNC signal directly via AC97SYNC register. Using
* TIMEDSYNC the controller will keep the SYNC high > 1us.
*/
ep93xx_ac97_write_reg(info, AC97SYNC, AC97SYNC_TIMEDSYNC);
ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
dev_warn(info->dev, "codec warm reset timeout\n");
mutex_unlock(&info->lock);
}
static void ep93xx_ac97_cold_reset(struct snd_ac97 *ac97)
{
struct ep93xx_ac97_info *info = ep93xx_ac97_info;
mutex_lock(&info->lock);
/*
* For doing cold reset, we disable the AC97 controller interface, clear
* WINT and CODECREADY bits, and finally enable the interface again.
*/
ep93xx_ac97_write_reg(info, AC97GCR, 0);
ep93xx_ac97_write_reg(info, AC97EOI, AC97EOI_CODECREADY | AC97EOI_WINT);
ep93xx_ac97_write_reg(info, AC97GCR, AC97GCR_AC97IFE);
/*
* Now, assert the reset and wait for the codec to become ready.
*/
ep93xx_ac97_write_reg(info, AC97RESET, AC97RESET_TIMEDRESET);
ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
dev_warn(info->dev, "codec cold reset timeout\n");
/*
* Give the codec some time to come fully out from the reset. This way
* we ensure that the subsequent reads/writes will work.
*/
usleep_range(15000, 20000);
mutex_unlock(&info->lock);
}
static irqreturn_t ep93xx_ac97_interrupt(int irq, void *dev_id)
{
struct ep93xx_ac97_info *info = dev_id;
unsigned status, mask;
/*
* Just mask out the interrupt and wake up the waiting thread.
* Interrupts are cleared via reading/writing to slot 1 & 2 registers by
* the waiting thread.
*/
status = ep93xx_ac97_read_reg(info, AC97GIS);
mask = ep93xx_ac97_read_reg(info, AC97IM);
mask &= ~status;
ep93xx_ac97_write_reg(info, AC97IM, mask);
complete(&info->done);
return IRQ_HANDLED;
}
struct snd_ac97_bus_ops soc_ac97_ops = {
.read = ep93xx_ac97_read,
.write = ep93xx_ac97_write,
.reset = ep93xx_ac97_cold_reset,
.warm_reset = ep93xx_ac97_warm_reset,
};
EXPORT_SYMBOL_GPL(soc_ac97_ops);
static int ep93xx_ac97_trigger(struct snd_pcm_substream *substream,
int cmd, struct snd_soc_dai *dai)
{
struct ep93xx_ac97_info *info = snd_soc_dai_get_drvdata(dai);
unsigned v = 0;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
/*
* Enable compact mode, TX slots 3 & 4, and the TX FIFO
* itself.
*/
v |= AC97TXCR_CM;
v |= AC97TXCR_TX3 | AC97TXCR_TX4;
v |= AC97TXCR_TEN;
ep93xx_ac97_write_reg(info, AC97TXCR(1), v);
} else {
/*
* Enable compact mode, RX slots 3 & 4, and the RX FIFO
* itself.
*/
v |= AC97RXCR_CM;
v |= AC97RXCR_RX3 | AC97RXCR_RX4;
v |= AC97RXCR_REN;
ep93xx_ac97_write_reg(info, AC97RXCR(1), v);
}
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
/*
* As per Cirrus EP93xx errata described below:
*
* http://www.cirrus.com/en/pubs/errata/ER667E2B.pdf
*
* we will wait for the TX FIFO to be empty before
* clearing the TEN bit.
*/
unsigned long timeout = jiffies + AC97_TIMEOUT;
do {
v = ep93xx_ac97_read_reg(info, AC97SR(1));
if (time_after(jiffies, timeout)) {
dev_warn(info->dev, "TX timeout\n");
break;
}
} while (!(v & (AC97SR_TXFE | AC97SR_TXUE)));
/* disable the TX FIFO */
ep93xx_ac97_write_reg(info, AC97TXCR(1), 0);
} else {
/* disable the RX FIFO */
ep93xx_ac97_write_reg(info, AC97RXCR(1), 0);
}
break;
default:
dev_warn(info->dev, "unknown command %d\n", cmd);
return -EINVAL;
}
return 0;
}
static int ep93xx_ac97_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct ep93xx_pcm_dma_params *dma_data;
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
dma_data = &ep93xx_ac97_pcm_out;
else
dma_data = &ep93xx_ac97_pcm_in;
snd_soc_dai_set_dma_data(dai, substream, dma_data);
return 0;
}
static const struct snd_soc_dai_ops ep93xx_ac97_dai_ops = {
.startup = ep93xx_ac97_startup,
.trigger = ep93xx_ac97_trigger,
};
static struct snd_soc_dai_driver ep93xx_ac97_dai = {
.name = "ep93xx-ac97",
.id = 0,
.ac97_control = 1,
.playback = {
.stream_name = "AC97 Playback",
.channels_min = 2,
.channels_max = 2,
.rates = SNDRV_PCM_RATE_8000_48000,
.formats = SNDRV_PCM_FMTBIT_S16_LE,
},
.capture = {
.stream_name = "AC97 Capture",
.channels_min = 2,
.channels_max = 2,
.rates = SNDRV_PCM_RATE_8000_48000,
.formats = SNDRV_PCM_FMTBIT_S16_LE,
},
.ops = &ep93xx_ac97_dai_ops,
};
static int __devinit ep93xx_ac97_probe(struct platform_device *pdev)
{
struct ep93xx_ac97_info *info;
int ret;
info = kzalloc(sizeof(struct ep93xx_ac97_info), GFP_KERNEL);
if (!info)
return -ENOMEM;
dev_set_drvdata(&pdev->dev, info);
mutex_init(&info->lock);
init_completion(&info->done);
info->dev = &pdev->dev;
info->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!info->mem) {
ret = -ENXIO;
goto fail_free_info;
}
info->irq = platform_get_irq(pdev, 0);
if (!info->irq) {
ret = -ENXIO;
goto fail_free_info;
}
if (!request_mem_region(info->mem->start, resource_size(info->mem),
pdev->name)) {
ret = -EBUSY;
goto fail_free_info;
}
info->regs = ioremap(info->mem->start, resource_size(info->mem));
if (!info->regs) {
ret = -ENOMEM;
goto fail_release_mem;
}
ret = request_irq(info->irq, ep93xx_ac97_interrupt, IRQF_TRIGGER_HIGH,
pdev->name, info);
if (ret)
goto fail_unmap_mem;
ep93xx_ac97_info = info;
platform_set_drvdata(pdev, info);
ret = snd_soc_register_dai(&pdev->dev, &ep93xx_ac97_dai);
if (ret)
goto fail_free_irq;
return 0;
fail_free_irq:
platform_set_drvdata(pdev, NULL);
free_irq(info->irq, info);
fail_unmap_mem:
iounmap(info->regs);
fail_release_mem:
release_mem_region(info->mem->start, resource_size(info->mem));
fail_free_info:
kfree(info);
return ret;
}
static int __devexit ep93xx_ac97_remove(struct platform_device *pdev)
{
struct ep93xx_ac97_info *info = platform_get_drvdata(pdev);
snd_soc_unregister_dai(&pdev->dev);
/* disable the AC97 controller */
ep93xx_ac97_write_reg(info, AC97GCR, 0);
free_irq(info->irq, info);
iounmap(info->regs);
release_mem_region(info->mem->start, resource_size(info->mem));
platform_set_drvdata(pdev, NULL);
kfree(info);
return 0;
}
static struct platform_driver ep93xx_ac97_driver = {
.probe = ep93xx_ac97_probe,
.remove = __devexit_p(ep93xx_ac97_remove),
.driver = {
.name = "ep93xx-ac97",
.owner = THIS_MODULE,
},
};
module_platform_driver(ep93xx_ac97_driver);
MODULE_DESCRIPTION("EP93xx AC97 ASoC Driver");
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ep93xx-ac97");