最近做了博创2410开发板上uda1341的驱动，从网上下了一些源代码，直接拿过来在2.6.24上行不通。然后就自己去看内核中和dma相关的代码，最终把驱动弄好了，能顺利播放音乐了。把移植过程介绍一下，供大家参考。
遇到的第一个问题是dma通道的映射问题。
通道映射不正确的话，uda1341就没有输出。这个问题我觉得是移植过程中解决的主要问题。关于2.6.24中dma的基本建立过程在我的另一篇文章中有介绍，大家可以看一下：
然后直接介绍移植过程中需要修改的地方。首先还是dma通道的问题。在内核的arch/arm/plat-s3c24xx/dma.c的s3c2410_dma_map_channel函数中修改如下：
static struct s3c2410_dma_chan *s3c2410_dma_map_channel(int channel)
{
struct s3c24xx_dma_order_ch *ord = NULL;
struct s3c24xx_dma_map *ch_map;
struct s3c2410_dma_chan *dmach;
int ch;
if (dma_sel.map == NULL || channel > dma_sel.map_size)
return NULL;
ch_map = dma_sel.map + channel;
/* first, try the board mapping */
#if 0 //这里
if (dma_order) {
ord = &dma_order->channels[channel];
for (ch = 0; ch < dma_channels; ch++) {
if (!is_channel_valid(ord->list[ch]))
continue;
if (s3c2410_chans[ord->list[ch]].in_use == 0) {
ch = ord->list[ch] & ~DMA_CH_VALID;
goto found;
}
}
if (ord->flags & DMA_CH_NEVER)
return NULL;
}
#endif //这里
/* second, search the channel map for first free */
就是注释掉一段代码就行了。
然后，还是同一个文件中，修改这个函数：s3c2410_dma_enqueue
这个函数的结尾：
} else if (chan->state == S3C2410_DMA_IDLE) {
if (chan->flags & S3C2410_DMAF_AUTOSTART) {
s3c2410_dma_ctrl(channel, S3C2410_DMAOP_START); //修改的只有这一行
}
}
local_irq_restore(flags);
return 0;
}
上面注释的那行，把第一个参数chan->number，换成了现在的channel。
ok，这个文件就改这些。
下面贴出uda1341.c这个文件：
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include #define DMA_BUF_WR 1
#define DMA_BUF_RD 0
#define DMA_CH1 DMACH_I2S_IN
#define DMA_CH2 DMACH_I2S_OUT
static struct clk *iis_clock;
static void __iomem *iis_base;
static struct s3c2410_dma_client s3c2410iis_dma_out= {
.name = "I2SSDO",
};
static struct s3c2410_dma_client s3c2410iis_dma_in = {
.name = "I2SSDI",
};
static void init_s3c2410_iis_bus(void);
#define DEF_VOLUME 65
/* UDA1341 Register bits */
#define UDA1341_ADDR 0x14
#define UDA1341_REG_DATA0 (UDA1341_ADDR + 0)
#define UDA1341_REG_STATUS (UDA1341_ADDR + 2)
/* status control */
#define STAT0 (0x00)
#define STAT0_RST (1 << 6)
#define STAT0_SC_MASK (3 << 4)
#define STAT0_SC_512FS (0 << 4)
#define STAT0_SC_384FS (1 << 4)
#define STAT0_SC_256FS (2 << 4)
#define STAT0_IF_MASK (7 << 1)
#define STAT0_IF_I2S (0 << 1)
#define STAT0_IF_LSB16 (1 << 1)
#define STAT0_IF_LSB18 (2 << 1)
#define STAT0_IF_LSB20 (3 << 1)
#define STAT0_IF_MSB (4 << 1)
#define STAT0_IF_LSB16MSB (5 << 1)
#define STAT0_IF_LSB18MSB (6 << 1)
#define STAT0_IF_LSB20MSB (7 << 1)
#define STAT0_DC_FILTER (1 << 0)
#define STAT0_DC_NO_FILTER (0 << 0)
#define STAT1 (0x80)
#define STAT1_DAC_GAIN (1 << 6) /* gain of DAC */
#define STAT1_ADC_GAIN (1 << 5) /* gain of ADC */
#define STAT1_ADC_POL (1 << 4) /* polarity of ADC */
#define STAT1_DAC_POL (1 << 3) /* polarity of DAC */
#define STAT1_DBL_SPD (1 << 2) /* double speed playback */
#define STAT1_ADC_ON (1 << 1) /* ADC powered */
#define STAT1_DAC_ON (1 << 0) /* DAC powered */
/* data0 direct control */
#define DATA0 (0x00)
#define DATA0_VOLUME_MASK (0x3f)
#define DATA0_VOLUME(x) (x)
#define DATA1 (0x40)
#define DATA1_BASS(x) ((x) << 2)
#define DATA1_BASS_MASK (15 << 2)
#define DATA1_TREBLE(x) ((x))
#define DATA1_TREBLE_MASK (3)
#define DATA2 (0x80)
#define DATA2_PEAKAFTER (0x1 << 5)
#define DATA2_DEEMP_NONE (0x0 << 3)
#define DATA2_DEEMP_32KHz (0x1 << 3)
#define DATA2_DEEMP_44KHz (0x2 << 3)
#define DATA2_DEEMP_48KHz (0x3 << 3)
#define DATA2_MUTE (0x1 << 2)
#define DATA2_FILTER_FLAT (0x0 << 0)
#define DATA2_FILTER_MIN (0x1 << 0)
#define DATA2_FILTER_MAX (0x3 << 0)
/* data0 extend control */
#define EXTADDR(n) (0xc0 | (n))
#define EXTDATA(d) (0xe0 | (d))
#define EXT0 0
#define EXT0_CH1_GAIN(x) (x)
#define EXT1 1
#define EXT1_CH2_GAIN(x) (x)
#define EXT2 2
#define EXT2_MIC_GAIN_MASK (7 << 2)
#define EXT2_MIC_GAIN(x) ((x) << 2)
#define EXT2_MIXMODE_DOUBLEDIFF (0)
#define EXT2_MIXMODE_CH1 (1)
#define EXT2_MIXMODE_CH2 (2)
#define EXT2_MIXMODE_MIX (3)
#define EXT4 4
#define EXT4_AGC_ENABLE (1 << 4)
#define EXT4_INPUT_GAIN_MASK (3)
#define EXT4_INPUT_GAIN(x) ((x) & 3)
#define EXT5 5
#define EXT5_INPUT_GAIN(x) ((x) >> 2)
#define EXT6 6
#define EXT6_AGC_CONSTANT_MASK (7 << 2)
#define EXT6_AGC_CONSTANT(x) ((x) << 2)
#define EXT6_AGC_LEVEL_MASK (3)
#define EXT6_AGC_LEVEL(x) (x)
#define AUDIO_NAME "UDA1341"
#define AUDIO_NAME_VERBOSE "UDA1341 audio driver"
#define AUDIO_FMT_MASK (AFMT_S16_LE)
#define AUDIO_FMT_DEFAULT (AFMT_S16_LE)
#define AUDIO_CHANNELS_DEFAULT 2
#define AUDIO_RATE_DEFAULT 8000
#define AUDIO_NBFRAGS_DEFAULT 8
#define AUDIO_FRAGSIZE_DEFAULT 8192
#define S_CLOCK_FREQ 384
typedef struct {
int size; /* buffer size */
char *start; /* point to actual buffer */
dma_addr_t dma_addr; /* physical buffer address */
struct semaphore sem; /* down before touching the buffer */
int master; /* owner for buffer allocation, contain size when true */
} audio_buf_t;
typedef struct {
audio_buf_t *buffers; /* pointer to audio buffer structures */
audio_buf_t *buf; /* current buffer used by read/write */
u_int buf_idx; /* index for the pointer above */
u_int fragsize; /* fragment i.e. buffer size */
u_int nbfrags; /* nbr of fragments */
enum dma_ch dmach;
} audio_stream_t;
static audio_stream_t output_stream;
static audio_stream_t input_stream;
#define NEXT_BUF(_s_,_b_) { \
(_s_)->_b_##_idx++; \
(_s_)->_b_##_idx %= (_s_)->nbfrags; \
(_s_)->_b_ = (_s_)->buffers + (_s_)->_b_##_idx; }
static u_int audio_rate;
static int audio_channels;
static int audio_fmt;
static u_int audio_fragsize;
static u_int audio_nbfrags;
static int audio_rd_refcount;
static int audio_wr_refcount;
#define audio_active (audio_rd_refcount | audio_wr_refcount)
static int audio_dev_dsp;
static int audio_dev_mixer;
static int audio_mix_modcnt;
static int uda1341_volume;
static u8 uda_sampling;
static int uda1341_boost;
static int mixer_igain=0x4; /* -6db*/
static void uda1341_l3_address(u8 data)
{
int i;
unsigned long flags;
local_irq_save(flags);
s3c2410_gpio_setpin(S3C2410_GPG9,1);
s3c2410_gpio_setpin(S3C2410_GPG0,0);
udelay(10);
s3c2410_gpio_setpin(S3C2410_GPG8,0);
udelay(5);
for (i = 0; i < 8; i++) {
if (data & 0x1) {
s3c2410_gpio_setpin(S3C2410_GPG9,0);
s3c2410_gpio_setpin(S3C2410_GPG0,1);
udelay(1);
s3c2410_gpio_setpin(S3C2410_GPG9,1);
udelay(1);
} else {
s3c2410_gpio_setpin(S3C2410_GPG9,0);
s3c2410_gpio_setpin(S3C2410_GPG0,0);
udelay(1);
s3c2410_gpio_setpin(S3C2410_GPG9,1);
udelay(1);
}
data >>= 1;
}
udelay(5);
s3c2410_gpio_setpin(S3C2410_GPG8,1);
udelay(1);
local_irq_restore(flags);
}
static void uda1341_l3_data(u8 data)
{
int i;
unsigned long flags;
local_irq_save(flags);
s3c2410_gpio_setpin(S3C2410_GPG8,1);
udelay(5);
for (i = 0; i < 8; i++) {
if (data & 0x1) {
s3c2410_gpio_setpin(S3C2410_GPG9,0);
s3c2410_gpio_setpin(S3C2410_GPG0,1);
udelay(1);
s3c2410_gpio_setpin(S3C2410_GPG9,1);
udelay(1);
} else {
s3c2410_gpio_setpin(S3C2410_GPG9,0);
s3c2410_gpio_setpin(S3C2410_GPG0,0);
udelay(1);
s3c2410_gpio_setpin(S3C2410_GPG9,1);
udelay(1);
}
data >>= 1;
}
udelay(1);
s3c2410_gpio_setpin(S3C2410_GPG8, 0);
udelay(2);
s3c2410_gpio_setpin(S3C2410_GPG8, 1);
local_irq_restore(flags);
}
static void audio_clear_buf(audio_stream_t * s)
{
s3c2410_dma_ctrl(s->dmach, S3C2410_DMAOP_FLUSH);
if (s->buffers) {
int frag;
for (frag = 0; frag < s->nbfrags; frag++) {
if (!s->buffers[frag].master)
continue;
dma_free_coherent(NULL,
s->buffers[frag].master,
s->buffers[frag].start,
s->buffers[frag].dma_addr);
}
kfree(s->buffers);
s->buffers = NULL;
}
s->buf_idx = 0;
s->buf = NULL;
}
static int audio_setup_buf(audio_stream_t * s)
{
int frag;
int dmasize = 0;
char *dmabuf = 0;
dma_addr_t dmaphys = 0;
if (s->buffers)
return -EBUSY;
s->nbfrags = audio_nbfrags;
s->fragsize = audio_fragsize;
s->buffers = (audio_buf_t *)
kmalloc(sizeof(audio_buf_t) * s->nbfrags, GFP_KERNEL);
if (!s->buffers)
goto err;
memset(s->buffers, 0, sizeof(audio_buf_t) * s->nbfrags);
for (frag = 0; frag < s->nbfrags; frag++) {
audio_buf_t *b = &s->buffers[frag];
if (!dmasize) {
dmasize = (s->nbfrags - frag) * s->fragsize;
do {
dmabuf = dma_alloc_coherent(NULL, dmasize, &dmaphys, GFP_KERNEL|GFP_DMA);
if (!dmabuf)
dmasize -= s->fragsize;
} while (!dmabuf && dmasize);
if (!dmabuf)
goto err;
b->master = dmasize;
}
b->start = dmabuf;
b->dma_addr = dmaphys;
sema_init(&b->sem, 1);
dmabuf += s->fragsize;
dmaphys += s->fragsize;
dmasize -= s->fragsize;
}
s->buf_idx = 0;
s->buf = &s->buffers[0];
return 0;
err:
printk(AUDIO_NAME ": unable to allocate audio memory\n ");
audio_clear_buf(s);
return -ENOMEM;
}
static void audio_dmaout_done_callback(struct s3c2410_dma_chan *ch, void *buf, int size,enum s3c2410_dma_buffresult result)
{
audio_buf_t *b = (audio_buf_t *) buf;
up(&b->sem);
wake_up(&b->sem.wait);
}
static void audio_dmain_done_callback(struct s3c2410_dma_chan *ch, void *buf, int size,enum s3c2410_dma_buffresult result)
{
audio_buf_t *b = (audio_buf_t *) buf;
b->size = size;
up(&b->sem);
wake_up(&b->sem.wait);
}
/* using when write */
static int audio_sync(struct file *file)
{
audio_stream_t *s = &output_stream;
audio_buf_t *b = s->buf;
printk("audio_sync\n");
if (!s->buffers)
return 0;
if (b->size != 0) {
down(&b->sem);
s3c2410_dma_enqueue(s->dmach, (void *) b, b->dma_addr, b->size);
b->size = 0;
NEXT_BUF(s, buf);
}
b = s->buffers + ((s->nbfrags + s->buf_idx - 1) % s->nbfrags);
if (down_interruptible(&b->sem))
return -EINTR;
up(&b->sem);
return 0;
}
static inline int copy_from_user_mono_stereo(char *to, const char *from, int count)
{
u_int *dst = (u_int *)to;
const char *end = from + count;
if (!access_ok(VERIFY_READ, from, count))
return -EFAULT;
if ((int)from & 0x2) {
u_int v;
__get_user(v, (const u_short *)from); from += 2;
*dst++ = v | (v << 16);
}
while (from < end-2) {
u_int v, x, y;
__get_user(v, (const u_int *)from); from += 4;
x = v << 16;
x |= x >> 16;
y = v >> 16;
y |= y << 16;
*dst++ = x;
*dst++ = y;
}
if (from < end) {
u_int v;
__get_user(v, (const u_short *)from);
*dst = v | (v << 16);
}
return 0;
}
static ssize_t smdk2410_audio_write(struct file *file, const char *buffer,
size_t count, loff_t * ppos)
{
const char *buffer0 = buffer;
audio_stream_t *s = &output_stream;
int chunksize, ret = 0;
switch (file->f_flags & O_ACCMODE) {
case O_WRONLY:
case O_RDWR:
break;
default:
return -EPERM;
}
if (!s->buffers && audio_setup_buf(s))
return -ENOMEM;
count &= ~0x03;
while (count > 0) {
audio_buf_t *b = s->buf;
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
if (down_trylock(&b->sem))
break;
} else {
ret = -ERESTARTSYS;
if (down_interruptible(&b->sem))
break;
}
if (audio_channels == 2) {
chunksize = s->fragsize - b->size;
if (chunksize > count)
chunksize = count;
if (copy_from_user(b->start + b->size, buffer, chunksize)) {
up(&b->sem);
return -EFAULT;
}
b->size += chunksize;
} else {
chunksize = (s->fragsize - b->size) >> 1;
if (chunksize > count)
chunksize = count;
if (copy_from_user_mono_stereo(b->start + b->size,
buffer, chunksize)) {
up(&b->sem);
return -EFAULT;
}
b->size += chunksize*2;
}
buffer += chunksize;
count -= chunksize;
if (b->size < s->fragsize) {
up(&b->sem);
break;
}
ret = s3c2410_dma_enqueue(s->dmach, (void *)b, b->dma_addr, b->size);
if(ret) {
printk("dma enqueue failed.\n");
return ret;
}
b->size = 0;
NEXT_BUF(s, buf);
}
if ((buffer - buffer0))
ret = buffer - buffer0;
return ret;
}
static ssize_t smdk2410_audio_read(struct file *file, char *buffer,
size_t count, loff_t * ppos)
{
const char *buffer0 = buffer;
audio_stream_t *s = &input_stream;
int chunksize, ret = 0;
printk("audio_read: count=%d\n", count);
if (ppos != &file->f_pos)
return -ESPIPE;
if (!s->buffers) {
int i;
if (audio_setup_buf(s))
return -ENOMEM;
for (i = 0; i < s->nbfrags; i++) {
audio_buf_t *b = s->buf;
down(&b->sem);
s3c2410_dma_enqueue(s->dmach, (void *) b, b->dma_addr, s->fragsize);
NEXT_BUF(s, buf);
}
}
while (count > 0) {
audio_buf_t *b = s->buf;
/* Wait for a buffer to become full */
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
if (down_trylock(&b->sem))
break;
} else {
ret = -ERESTARTSYS;
if (down_interruptible(&b->sem))
break;
}
chunksize = b->size;
if (chunksize > count)
chunksize = count;
if (copy_to_user(buffer, b->start + s->fragsize - b->size,
chunksize)) {
up(&b->sem);
return -EFAULT;
}
b->size -= chunksize;
buffer += chunksize;
count -= chunksize;
if (b->size > 0) {
up(&b->sem);
break;
}
/* Make current buffer available for DMA again */
s3c2410_dma_enqueue(s->dmach, (void *) b, b->dma_addr, s->fragsize);
NEXT_BUF(s, buf);
}
if ((buffer - buffer0))
ret = buffer - buffer0;
printk("audio_read: return=%d\n", ret);
return ret;
}
static unsigned int smdk2410_audio_poll(struct file *file,
struct poll_table_struct *wait)
{
unsigned int mask = 0;
int i;
printk("audio_poll(): mode=%s\n",
(file->f_mode & FMODE_WRITE) ? "w" : "");
if (file->f_mode & FMODE_READ) {
if (!input_stream.buffers && audio_setup_buf(&input_stream))
return -ENOMEM;
poll_wait(file, &input_stream.buf->sem.wait, wait);
for (i = 0; i < input_stream.nbfrags; i++) {
if (atomic_read(&input_stream.buffers[i].sem.count) > 0)
mask |= POLLIN | POLLWRNORM;
break;
}
}
if (file->f_mode & FMODE_WRITE) {
if (!output_stream.buffers && audio_setup_buf(&output_stream))
return -ENOMEM;
poll_wait(file, &output_stream.buf->sem.wait, wait);
for (i = 0; i < output_stream.nbfrags; i++) {
if (atomic_read(&output_stream.buffers[i].sem.count) > 0)
mask |= POLLOUT | POLLWRNORM;
break;
}
}
return mask;
}
static loff_t smdk2410_audio_llseek(struct file *file, loff_t offset,
int origin)
{
return -ESPIPE;
}
static int smdk2410_mixer_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int ret;
long val = 0;
switch (cmd) {
case SOUND_MIXER_INFO:
{
mixer_info info;
strncpy(info.id, "UDA1341", sizeof(info.id));
strncpy(info.name,"Philips UDA1341", sizeof(info.name));
info.modify_counter = audio_mix_modcnt;
return copy_to_user((void *)arg, &info, sizeof(info));
}
case SOUND_OLD_MIXER_INFO:
{
_old_mixer_info info;
strncpy(info.id, "UDA1341", sizeof(info.id));
strncpy(info.name,"Philips UDA1341", sizeof(info.name));
return copy_to_user((void *)arg, &info, sizeof(info));
}
case SOUND_MIXER_READ_STEREODEVS:
return put_user(0, (long *) arg);
case SOUND_MIXER_READ_CAPS:
val = SOUND_CAP_EXCL_INPUT;
return put_user(val, (long *) arg);
case SOUND_MIXER_WRITE_VOLUME:
ret = get_user(val, (long *) arg);
if (ret)
return ret;
uda1341_volume = 63 - (((val & 0xff) + 1) * 63) / 100;
uda1341_l3_address(UDA1341_REG_DATA0);
uda1341_l3_data(uda1341_volume);
break;
case SOUND_MIXER_READ_VOLUME:
val = ((63 - uda1341_volume) * 100) / 63;
val |= val << 8;
return put_user(val, (long *) arg);
case SOUND_MIXER_READ_IGAIN:
val = ((31- mixer_igain) * 100) / 31;
return put_user(val, (int *) arg);
case SOUND_MIXER_WRITE_IGAIN:
ret = get_user(val, (int *) arg);
if (ret)
return ret;
mixer_igain = 31 - (val * 31 / 100);
/* use mixer gain channel 1*/
uda1341_l3_address(UDA1341_REG_DATA0);
uda1341_l3_data(EXTADDR(EXT0));
uda1341_l3_data(EXTDATA(EXT0_CH1_GAIN(mixer_igain)));
break;
default:
return -ENOSYS;
}
audio_mix_modcnt++;
return 0;
}
static int iispsr_value(int s_bit_clock, int sample_rate)
{
unsigned int i,j,prescaler = 0;
i = s_bit_clock*sample_rate;
prescaler = clk_get_rate(iis_clock)/i;
j = clk_get_rate(iis_clock)%i;
if(j<(i/2))
return (prescaler - 1);
return prescaler;
}
static int audio_set_dsp_speed(long val)
{
unsigned long iispsr = 0;
unsigned long value = 0;
value = iispsr_value(S_CLOCK_FREQ, val);
iispsr = (value<<5)|value;
writel(iispsr, iis_base + S3C2410_IISPSR);
iispsr = readl(iis_base + S3C2410_IISPSR);
return (audio_rate = val);
}
static int smdk2410_audio_ioctl(struct inode *inode, struct file *file,
uint cmd, ulong arg)
{
long val;
switch (cmd) {
case SNDCTL_DSP_SETFMT:
get_user(val, (long *) arg);
if (val & AUDIO_FMT_MASK) {
audio_fmt = val;
break;
} else
return -EINVAL;
case SNDCTL_DSP_CHANNELS:
case SNDCTL_DSP_STEREO:
get_user(val, (long *) arg);
if (cmd == SNDCTL_DSP_STEREO)
val = val ? 2 : 1;
if (val != 1 && val != 2)
return -EINVAL;
audio_channels = val;
break;
case SOUND_PCM_READ_CHANNELS:
put_user(audio_channels, (long *) arg);
break;
case SNDCTL_DSP_SPEED:
get_user(val, (long *) arg);
val = audio_set_dsp_speed(val);
if (val < 0)
return -EINVAL;
put_user(val, (long *) arg);
break;
case SOUND_PCM_READ_RATE:
put_user(audio_rate, (long *) arg);
break;
case SNDCTL_DSP_GETFMTS:
put_user(AUDIO_FMT_MASK, (long *) arg);
break;
case SNDCTL_DSP_GETBLKSIZE:
if(file->f_mode & FMODE_WRITE)
return put_user(audio_fragsize, (long *) arg);
else
return put_user(audio_fragsize, (int *) arg);
case SNDCTL_DSP_SETFRAGMENT:
if (file->f_mode & FMODE_WRITE) {
if (output_stream.buffers)
return -EBUSY;
get_user(val, (long *) arg);
audio_fragsize = 1 << (val & 0xFFFF);
if (audio_fragsize < 16)
audio_fragsize = 16;
if (audio_fragsize > 16384)
audio_fragsize = 16384;
audio_nbfrags = (val >> 16) & 0x7FFF;
if (audio_nbfrags < 2)
audio_nbfrags = 2;
if (audio_nbfrags * audio_fragsize > 128 * 1024)
audio_nbfrags = 128 * 1024 / audio_fragsize;
if (audio_setup_buf(&output_stream))
return -ENOMEM;
}
if (file->f_mode & FMODE_READ) {
if (input_stream.buffers)
return -EBUSY;
get_user(val, (int *) arg);
audio_fragsize = 1 << (val & 0xFFFF);
if (audio_fragsize < 16)
audio_fragsize = 16;
if (audio_fragsize > 16384)
audio_fragsize = 16384;
audio_nbfrags = (val >> 16) & 0x7FFF;
if (audio_nbfrags < 2)
audio_nbfrags = 2;
if (audio_nbfrags * audio_fragsize > 128 * 1024)
audio_nbfrags = 128 * 1024 / audio_fragsize;
if (audio_setup_buf(&input_stream))
return -ENOMEM;
}
break;
case SNDCTL_DSP_SYNC:
return audio_sync(file);
case SNDCTL_DSP_GETOSPACE:
{
audio_stream_t *s = &output_stream;
audio_buf_info *inf = (audio_buf_info *) arg;
int err = access_ok(VERIFY_WRITE, inf, sizeof(*inf));
int i;
int frags = 0, bytes = 0;
if (err)
return err;
for (i = 0; i < s->nbfrags; i++) {
if (atomic_read(&s->buffers[i].sem.count) > 0) {
if (s->buffers[i].size == 0) frags++;
bytes += s->fragsize - s->buffers[i].size;
}
}
put_user(frags, &inf->fragments);
put_user(s->nbfrags, &inf->fragstotal);
put_user(s->fragsize, &inf->fragsize);
put_user(bytes, &inf->bytes);
break;
}
case SNDCTL_DSP_GETISPACE:
{
audio_stream_t *s = &input_stream;
audio_buf_info *inf = (audio_buf_info *) arg;
int err = access_ok(VERIFY_WRITE, inf, sizeof(*inf));
int i;
int frags = 0, bytes = 0;
if (!(file->f_mode & FMODE_READ))
return -EINVAL;
if (err)
return err;
for(i = 0; i < s->nbfrags; i++){
if (atomic_read(&s->buffers[i].sem.count) > 0)
{
if (s->buffers[i].size == s->fragsize)
frags++;
bytes += s->buffers[i].size;
}
}
put_user(frags, &inf->fragments);
put_user(s->nbfrags, &inf->fragstotal);
put_user(s->fragsize, &inf->fragsize);
put_user(bytes, &inf->bytes);
break;
}
case SNDCTL_DSP_RESET:
if (file->f_mode & FMODE_READ) {
audio_clear_buf(&input_stream);
}
if (file->f_mode & FMODE_WRITE) {
audio_clear_buf(&output_stream);
}
return 0;
case SNDCTL_DSP_NONBLOCK:
file->f_flags |= O_NONBLOCK;
return 0;
case SNDCTL_DSP_POST:
case SNDCTL_DSP_SUBDIVIDE:
case SNDCTL_DSP_GETCAPS:
case SNDCTL_DSP_GETTRIGGER:
case SNDCTL_DSP_SETTRIGGER:
case SNDCTL_DSP_GETIPTR:
case SNDCTL_DSP_GETOPTR:
case SNDCTL_DSP_MAPINBUF:
case SNDCTL_DSP_MAPOUTBUF:
case SNDCTL_DSP_SETSYNCRO:
case SNDCTL_DSP_SETDUPLEX:
return -ENOSYS;
default:
return smdk2410_mixer_ioctl(inode, file, cmd, arg);
}
return 0;
}
static int smdk2410_audio_open(struct inode *inode, struct file *file)
{
int cold = !audio_active;
printk("audio open\n");
if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
if (audio_rd_refcount || audio_wr_refcount)
return -EBUSY;
audio_rd_refcount++;
} else if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
if (audio_wr_refcount)
return -EBUSY;
audio_wr_refcount++;
} else if ((file->f_flags & O_ACCMODE) == O_RDWR) {
if (audio_rd_refcount || audio_wr_refcount)
return -EBUSY;
audio_rd_refcount++;
audio_wr_refcount++;
} else
return -EINVAL;
if (cold) {
audio_rate = AUDIO_RATE_DEFAULT;
audio_channels = AUDIO_CHANNELS_DEFAULT;
audio_fragsize = AUDIO_FRAGSIZE_DEFAULT;
audio_nbfrags = AUDIO_NBFRAGS_DEFAULT;
init_s3c2410_iis_bus();
if ((file->f_mode & FMODE_WRITE)){
audio_clear_buf(&output_stream);
}
if ((file->f_mode & FMODE_READ))
audio_clear_buf(&input_stream);
}
return 0;
}
static int smdk2410_mixer_open(struct inode *inode, struct file *file)
{
return 0;
}
static int smdk2410_audio_release(struct inode *inode, struct file *file)
{
if (file->f_mode & FMODE_READ) {
if (audio_rd_refcount == 1)
audio_clear_buf(&input_stream);
audio_rd_refcount = 0;
}
if(file->f_mode & FMODE_WRITE) {
if (audio_wr_refcount == 1) {
audio_sync(file);
audio_clear_buf(&output_stream);
audio_wr_refcount = 0;
}
}
return 0;
}
static int smdk2410_mixer_release(struct inode *inode, struct file *file)
{
return 0;
}
static struct file_operations smdk2410_audio_fops = {
.llseek = smdk2410_audio_llseek,
.write = smdk2410_audio_write,
.read = smdk2410_audio_read,
.poll = smdk2410_audio_poll,
.ioctl = smdk2410_audio_ioctl,
.open = smdk2410_audio_open,
.release = smdk2410_audio_release
};
static struct file_operations smdk2410_mixer_fops = {
.ioctl = smdk2410_mixer_ioctl,
.open = smdk2410_mixer_open,
.release = smdk2410_mixer_release
};
static void init_uda1341(void)
{
unsigned long flags;
uda1341_volume = 62 - ((DEF_VOLUME * 61) / 100);
uda1341_boost = 0;
uda_sampling = DATA2_DEEMP_NONE;
uda_sampling &= ~(DATA2_MUTE);
local_irq_save(flags);
s3c2410_gpio_setpin(S3C2410_GPG9, 1);
s3c2410_gpio_setpin(S3C2410_GPG8, 1);
local_irq_restore(flags);
uda1341_l3_address(UDA1341_REG_STATUS);
uda1341_l3_data(STAT0_RST);
uda1341_l3_address(UDA1341_REG_STATUS);
uda1341_l3_data(STAT0_SC_384FS | STAT0_IF_MSB | STAT0_DC_FILTER);
uda1341_l3_data(STAT1 | STAT1_DAC_GAIN | STAT1_ADC_GAIN | STAT1_ADC_ON | STAT1_DAC_ON);
uda1341_l3_address(UDA1341_REG_DATA0);
uda1341_l3_data(DATA0 |DATA0_VOLUME(uda1341_volume));
uda1341_l3_data(DATA1 |DATA1_BASS(uda1341_boost)| DATA1_TREBLE(0));
uda1341_l3_data(DATA2 |uda_sampling);
uda1341_l3_data(EXTADDR(EXT2));
uda1341_l3_data(EXTDATA(EXT2_MIC_GAIN(0x6)| EXT2_MIXMODE_CH2));
uda1341_l3_data(EXTADDR(EXT5));
uda1341_l3_data(EXTDATA(0x7));
local_irq_save(flags);
s3c2410_gpio_setpin(S3C2410_GPG9, 1);
s3c2410_gpio_setpin(S3C2410_GPG8, 0);
local_irq_restore(flags);
}
static void init_s3c2410_iis_bus(void){
unsigned long iiscon, iismod, iisfcon;
clk_enable(iis_clock);
iiscon = iismod = iisfcon = 0;
iiscon |= S3C2410_IISCON_PSCEN; // Enable prescaler
iiscon |= S3C2410_IISCON_IISEN; // Enable interface
iiscon |= S3C2410_IISCON_RXDMAEN; //Enable RX DMA service request
iiscon |= S3C2410_IISCON_TXDMAEN; //Enable TX DMA service request
iismod |= S3C2410_IISMOD_LR_LLOW; // Low for left channel
iismod |= S3C2410_IISMOD_MSB;
iismod |= S3C2410_IISMOD_16BIT; // Serial data bit/channel is 16 bit
iismod |= S3C2410_IISMOD_384FS; // Master clock freq = 384 fs
iismod |= S3C2410_IISMOD_TXRXMODE; //Set RX Mode
iismod |= S3C2410_IISMOD_32FS; // 32 fs
iisfcon|= S3C2410_IISFCON_RXDMA; //Set RX FIFO acces mode to DMA
iisfcon|= S3C2410_IISFCON_RXENABLE; //Enable RX Fifo
iisfcon|= S3C2410_IISFCON_TXDMA; //Set RX FIFO acces mode to DMA
iisfcon|= S3C2410_IISFCON_TXENABLE;
audio_set_dsp_speed(44100);
writel(iismod, iis_base + S3C2410_IISMOD);
writel(iisfcon, iis_base + S3C2410_IISFCON);
writel(iiscon, iis_base + S3C2410_IISCON);
}
static int __init audio_init_dma(audio_stream_t * s, char *desc)
{
int ret ;
enum s3c2410_dmasrc source;
int hwcfg;
unsigned long devaddr;
int dcon;
unsigned int flags = 0;
if(s->dmach == DMA_CH2){
source = S3C2410_DMASRC_MEM;
hwcfg = 3;
devaddr = 0x55000010;
dcon = 0xa0800000;
flags = S3C2410_DMAF_AUTOSTART;
ret = s3c2410_dma_request(s->dmach, &s3c2410iis_dma_out, NULL);
s3c2410_dma_devconfig(s->dmach, source, hwcfg, devaddr);
s3c2410_dma_config(s->dmach, 2, dcon);
s3c2410_dma_set_buffdone_fn(s->dmach, audio_dmaout_done_callback);
s3c2410_dma_setflags(s->dmach, flags);
return ret;
}
else if(s->dmach == DMA_CH1){
source =S3C2410_DMASRC_HW;
hwcfg =3;
devaddr = 0x55000010;
dcon = 0xa2900000;
flags = S3C2410_DMAF_AUTOSTART;
ret = s3c2410_dma_request(s->dmach, &s3c2410iis_dma_in, NULL);
s3c2410_dma_devconfig(s->dmach, source, hwcfg, devaddr);
s3c2410_dma_config(s->dmach, 2, dcon);
s3c2410_dma_set_buffdone_fn(s->dmach, audio_dmain_done_callback);
s3c2410_dma_setflags(s->dmach, flags);
return ret ;
}
else
return 1;
}
static int audio_clear_dma(audio_stream_t * s,struct s3c2410_dma_client *client)
{
s3c2410_dma_set_buffdone_fn(s->dmach, NULL);
s3c2410_dma_free(s->dmach, client);
return 0;
}
static int __init s3c2410iis_probe(struct platform_device *pdev) {
struct resource *res;
int size;
unsigned long flags;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
printk(KERN_INFO "failed to get memory region resouce\n");
return -ENOENT;
}
if (!request_mem_region(res->start, 0x20, pdev->name)) {
printk(KERN_INFO "failed to get memory region\n");
return -EBUSY;
}
size = (res->end - res->start) + 1;
iis_base = ioremap(res->start, size);
if (iis_base == NULL) {
printk(KERN_INFO "failed to ioremap() region\n");
return -EINVAL;
}
iis_clock = clk_get(&pdev->dev, "iis");
if (iis_clock == NULL) {
printk(KERN_INFO "failed to find clock source\n");
return -ENOENT;
}
clk_enable(iis_clock);
local_irq_save(flags);
/* GPB 4: L3CLOCK, OUTPUT */
s3c2410_gpio_cfgpin(S3C2410_GPG9, S3C2410_GPG9_OUTP);
s3c2410_gpio_pullup(S3C2410_GPG9, 1);
/* GPB 3: L3DATA, OUTPUT */
s3c2410_gpio_cfgpin(S3C2410_GPG0,S3C2410_GPG0_OUTP);
s3c2410_gpio_pullup(S3C2410_GPG0, 1);
/* GPB 2: L3MODE, OUTPUT */
s3c2410_gpio_cfgpin(S3C2410_GPG8,S3C2410_GPG8_OUTP);
s3c2410_gpio_pullup(S3C2410_GPG8, 1);
/* GPE 3: I2SSDI */
s3c2410_gpio_cfgpin(S3C2410_GPE3,S3C2410_GPE3_I2SSDI);
s3c2410_gpio_pullup(S3C2410_GPE3, 0);
/* GPE 0: I2SLRCK */
s3c2410_gpio_cfgpin(S3C2410_GPE0,S3C2410_GPE0_I2SLRCK);
s3c2410_gpio_pullup(S3C2410_GPE0, 0);
/* GPE 1: I2SSCLK */
s3c2410_gpio_cfgpin(S3C2410_GPE1,S3C2410_GPE1_I2SSCLK);
s3c2410_gpio_pullup(S3C2410_GPE1, 0);
/* GPE 2: CDCLK */
s3c2410_gpio_cfgpin(S3C2410_GPE2,S3C2410_GPE2_CDCLK);
s3c2410_gpio_pullup(S3C2410_GPE2, 0);
/* GPE 4: I2SSDO */
s3c2410_gpio_cfgpin(S3C2410_GPE4,S3C2410_GPE4_I2SSDO);
s3c2410_gpio_pullup(S3C2410_GPE4, 0);
local_irq_restore(flags);
init_uda1341();
output_stream.dmach = DMA_CH2;
if (audio_init_dma(&output_stream, "UDA1341 out")) {
audio_clear_dma(&output_stream,&s3c2410iis_dma_out);
printk( KERN_WARNING AUDIO_NAME_VERBOSE
": unable to get DMA channels\n" );
return -EBUSY;
}
input_stream.dmach = DMA_CH1;
if (audio_init_dma(&input_stream, "UDA1341 in")) {
audio_clear_dma(&input_stream,&s3c2410iis_dma_in);
printk( KERN_WARNING AUDIO_NAME_VERBOSE
": unable to get DMA channels\n" );
return -EBUSY;
}
audio_dev_dsp = register_sound_dsp(&smdk2410_audio_fops, -1);
audio_dev_mixer = register_sound_mixer(&smdk2410_mixer_fops, -1);
printk(AUDIO_NAME_VERBOSE " initialized\n");
return 0;
}
static int s3c2410iis_remove(struct platform_device *dev) {
unregister_sound_dsp(audio_dev_dsp);
unregister_sound_mixer(audio_dev_mixer);
audio_clear_dma(&output_stream,&s3c2410iis_dma_out);
audio_clear_dma(&input_stream,&s3c2410iis_dma_in); /* input */
printk(AUDIO_NAME_VERBOSE " unloaded\n");
return 0;
}
static struct platform_driver s3c2410iis_driver = {
.probe = s3c2410iis_probe,
.remove = s3c2410iis_remove,
.driver = {
.name = "s3c2410-iis",
.owner = THIS_MODULE,
},
};
static int __init s3c2410_uda1341_init(void) {
memzero(&input_stream, sizeof(audio_stream_t));
memzero(&output_stream, sizeof(audio_stream_t));
return platform_driver_register(&s3c2410iis_driver);
}
static void __exit s3c2410_uda1341_exit(void) {
platform_driver_unregister(&s3c2410iis_driver);
}
module_init(s3c2410_uda1341_init);
module_exit(s3c2410_uda1341_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("S3C2410 uda1341 sound driver");
把上面的文件保存到sound/oss中，然后修改sound/oss中的kconfig和makefile，使内核加入该文件，然后编译就可以了。
值得注意的地方是，在驱动程序中DMA_CH1和DMA_CH2我是定义成DMACH_I2S_IN和DMACH_I2S_OUT，与其他人的程序中有一定的区别。上面两个量是枚举类型，大家可以查看include/asm-arm/plat-s3c24xx/dma.h文件，里面有它们的定义。
