声卡驱动框架

Posted zsy12138

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修改内核的s3c2410-wm8976.c文件,让其支持开发板的声卡

框架入口源文件:s3c2410-wm8976.c

(可根据入口源文件,再按着框架到内核走一遍)

内核版本:linux_2.6.22.6 硬件平台:JZ2440

 


以下是驱动框架:

技术图片


以下是驱动代码:

#include <linux/module.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/poll.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/sound.h>
#include <linux/soundcard.h>

#include <linux/pm.h>
#include <linux/clk.h>
#include <linux/platform_device.h>

#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/hardware.h>
#include <asm/semaphore.h>
#include <asm/dma.h>
#include <asm/arch/dma.h>
#include <asm/arch/regs-gpio.h>
#include <asm/arch/regs-iis.h>
#include <asm/arch/regs-clock.h>
#include <linux/dma-mapping.h>
#include <asm/dma-mapping.h>
#include <asm/arch/hardware.h>
#include <asm/arch/map.h>

#define PFX "s3c2410-uda1341-superlp: "

#define MAX_DMA_CHANNELS 0

/* The S3C2410 has four internal DMA channels. */

#define MAX_S3C2410_DMA_CHANNELS S3C2410_DMA_CHANNELS


#define DMA_BUF_WR 1
#define DMA_BUF_RD 0


#define dma_wrreg(chan, reg, val) __raw_writel((val), (chan)->regs + (reg))


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",
};



#ifdef DEBUG
#define DPRINTK printk
#else
#define DPRINTK( x... )
#endif

static void init_s3c2410_iis_bus_rx(void);
static void init_s3c2410_iis_bus_tx(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 44100

#define AUDIO_NBFRAGS_DEFAULT 8
#define AUDIO_FRAGSIZE_DEFAULT 8192

#define S_CLOCK_FREQ 384
#define PCM_ABS(a) (a < 0 ? -a : a)

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 */
    dmach_t dma_ch; /* DMA channel (channel2 for audio) */
    u_int dma_ok;
} audio_stream_t;

static audio_stream_t output_stream;
static audio_stream_t input_stream; /* input */

#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);

// write_gpio_bit(GPIO_L3MODE, 0);
    s3c2410_gpio_setpin(S3C2410_GPB2,0);
// write_gpio_bit(GPIO_L3CLOCK, 1);
    s3c2410_gpio_setpin(S3C2410_GPB4,1);
    udelay(1);

    for (i = 0; i < 8; i++) {
        if (data & 0x1) {
            s3c2410_gpio_setpin(S3C2410_GPB4,0);
            s3c2410_gpio_setpin(S3C2410_GPB3,1);
            udelay(1);
            s3c2410_gpio_setpin(S3C2410_GPB4,1);
        } else {
            s3c2410_gpio_setpin(S3C2410_GPB4,0);
            s3c2410_gpio_setpin(S3C2410_GPB3,0);
            udelay(1);
            s3c2410_gpio_setpin(S3C2410_GPB4,1);
        }
        data >>= 1;
    }

    s3c2410_gpio_setpin(S3C2410_GPB2,1);
    s3c2410_gpio_setpin(S3C2410_GPB4,1);
    local_irq_restore(flags);
}

static void uda1341_l3_data(u8 data)
{
    int i;
    unsigned long flags;

    local_irq_save(flags);
    udelay(1);

    for (i = 0; i < 8; i++) {
        if (data & 0x1) {
            s3c2410_gpio_setpin(S3C2410_GPB4,0);
            s3c2410_gpio_setpin(S3C2410_GPB3,1);
            udelay(1);
            s3c2410_gpio_setpin(S3C2410_GPB4,1);
        } else {
            s3c2410_gpio_setpin(S3C2410_GPB4,0);
            s3c2410_gpio_setpin(S3C2410_GPB3,0);
            udelay(1);
            s3c2410_gpio_setpin(S3C2410_GPB4,1);
        }

        data >>= 1;
    }

    local_irq_restore(flags);
}

static void audio_clear_buf(audio_stream_t * s)
{
    DPRINTK("audio_clear_buf
");

    if(s->dma_ok) s3c2410_dma_ctrl(s->dma_ch, 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);
        DPRINTK("buf %d: start %p dma %d
", frag, b->start, b->dma_addr);

        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
 ");
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;

    DPRINTK("audio_sync
");

    if (!s->buffers)
        return 0;

    if (b->size != 0) {
        down(&b->sem);
        s3c2410_dma_enqueue(s->dma_ch, (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;

    DPRINTK("audio_write : start count=%d
", count);

    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;
            DPRINTK("write %d to %d
", chunksize, s->buf_idx);
            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;
            DPRINTK("write %d to %d
", chunksize*2, s->buf_idx);
            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;
        }

        if((ret = s3c2410_dma_enqueue(s->dma_ch, (void *) b, b->dma_addr, b->size))) {
            printk(PFX"dma enqueue failed.
");
            return ret;
        }
        b->size = 0;
        NEXT_BUF(s, buf);
    }

    if ((buffer - buffer0))
        ret = buffer - buffer0;

    DPRINTK("audio_write : end count=%d

", ret);

    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;

    DPRINTK("audio_read: count=%d
", 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->dma_ch, (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;
        DPRINTK("read %d from %d
", chunksize, s->buf_idx);
        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->dma_ch, (void *) b, b->dma_addr, s->fragsize);

            NEXT_BUF(s, buf);
    }

    if ((buffer - buffer0))
        ret = buffer - buffer0;

    // DPRINTK("audio_read: return=%d
", ret);

    return ret;
}


static unsigned int smdk2410_audio_poll(struct file *file,
                    struct poll_table_struct *wait)
{
    unsigned int mask = 0;
    int i;

    DPRINTK("audio_poll(): mode=%s
",
        (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;
        }
    }

    DPRINTK("audio_poll() returned mask of %s
",
        (mask & POLLOUT) ? "w" : "");

    return mask;
}


static loff_t smdk2410_audio_llseek(struct file *file, loff_t offset,
                    int origin)
{
    return -ESPIPE;
}

                    static void wm8976_write_reg(unsigned char reg, unsigned int data)
                    {
                        int i;
                        unsigned long flags;
                        unsigned short val = (reg << 9) | (data & 0x1ff);
                    
                        s3c2410_gpio_setpin(S3C2410_GPB2,1);
                        s3c2410_gpio_setpin(S3C2410_GPB3,1);
                        s3c2410_gpio_setpin(S3C2410_GPB4,1);
                    
                        local_irq_save(flags);
                    
                        for (i = 0; i < 16; i++){
                            if (val & (1<<15))
                            {
                                s3c2410_gpio_setpin(S3C2410_GPB4,0);
                                s3c2410_gpio_setpin(S3C2410_GPB3,1);
                                udelay(1);
                                s3c2410_gpio_setpin(S3C2410_GPB4,1);            
                            }
                            else
                            {
                                s3c2410_gpio_setpin(S3C2410_GPB4,0);
                                s3c2410_gpio_setpin(S3C2410_GPB3,0);
                                udelay(1);
                                s3c2410_gpio_setpin(S3C2410_GPB4,1);            
                            }
                    
                            val = val << 1;
                        }
                    
                        s3c2410_gpio_setpin(S3C2410_GPB2,0);    
                        udelay(1);
                        s3c2410_gpio_setpin(S3C2410_GPB2,1);
                        s3c2410_gpio_setpin(S3C2410_GPB3,1);
                        s3c2410_gpio_setpin(S3C2410_GPB4,1);
                        
                        local_irq_restore(flags);    
                    }

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;
                                
                                            /* ioctl: val越大表示音量越大, 0-最小, 100-最大
                                             * UDA1341: 寄存器的值越小音量越大
                                             * WM8976: 52,53号寄存器bit[5:0]表示音量, 值越大音量越大, 0-63
                                             */
                                            
                                            uda1341_volume = (((val & 0xff) + 1) * 63) / 100;
                                            wm8976_write_reg(52, (1<<8)|uda1341_volume);
                                            wm8976_write_reg(53, (1<<8)|uda1341_volume);
                                            //uda1341_l3_address(UDA1341_REG_DATA0);
                                            //uda1341_l3_data(uda1341_volume);
                                            break;
                                
                                        case SOUND_MIXER_READ_VOLUME:
                                            val = (uda1341_volume * 100) / 63;
                                            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:
                                            DPRINTK("mixer ioctl %u unknown
", cmd);
                                            return -ENOSYS;
                                    }
                                
                                    audio_mix_modcnt++;
                                    return 0;
                                }



static int iispsr_value(int s_bit_clock, int sample_rate)
{
    int i, prescaler = 0;
    unsigned long tmpval;
    unsigned long tmpval384;
    unsigned long tmpval384min = 0xffff;

    tmpval384 = clk_get_rate(iis_clock) / s_bit_clock;
//    tmpval384 = s3c2410_get_bus_clk(GET_PCLK) / s_bit_clock;

    for (i = 0; i < 32; i++) {
        tmpval = tmpval384/(i+1);
        if (PCM_ABS((sample_rate - tmpval)) < tmpval384min) {
            tmpval384min = PCM_ABS((sample_rate - tmpval));
            prescaler = i;
        }
    }

    DPRINTK("prescaler = %d
", prescaler);

    return prescaler;
}


static long audio_set_dsp_speed(long val)
{
    unsigned int prescaler;
    prescaler=(IISPSR_A(iispsr_value(S_CLOCK_FREQ, val))
            | IISPSR_B(iispsr_value(S_CLOCK_FREQ, val)));
    __raw_writel(prescaler, iis_base + S3C2410_IISPSR);

    printk(PFX "audio_set_dsp_speed:%ld prescaler:%i
",val,prescaler);
    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;

    DPRINTK("audio_open
");
    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;
            if ((file->f_mode & FMODE_WRITE)){
                init_s3c2410_iis_bus_tx();
                audio_clear_buf(&output_stream);
            }
            if ((file->f_mode & FMODE_READ)){
                init_s3c2410_iis_bus_rx();
                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)
{
    DPRINTK("audio_release
");

    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)
{

    /* GPB 4: L3CLOCK */
    /* GPB 3: L3DATA */
    /* GPB 2: L3MODE */

    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_GPB2,1);//L3MODE=1
    s3c2410_gpio_setpin(S3C2410_GPB4,1);//L3CLOCK=1
    local_irq_restore(flags);

    uda1341_l3_address(UDA1341_REG_STATUS);
    uda1341_l3_data(0x40 | STAT0_SC_384FS | STAT0_IF_MSB|STAT0_DC_FILTER); // reset uda1341
    uda1341_l3_data(STAT1 | STAT1_ADC_ON | STAT1_DAC_ON);

    uda1341_l3_address(UDA1341_REG_DATA0);
    uda1341_l3_data(DATA0 |DATA0_VOLUME(0x0)); // maximum volume
    uda1341_l3_data(DATA1 |DATA1_BASS(uda1341_boost)| DATA1_TREBLE(0));
    uda1341_l3_data((DATA2 |DATA2_DEEMP_NONE) &~(DATA2_MUTE));
    uda1341_l3_data(EXTADDR(EXT2));
    uda1341_l3_data(EXTDATA(EXT2_MIC_GAIN(0x6)) | EXT2_MIXMODE_CH1);//input channel 1 select(input channel 2 off)

}




static void init_wm8976(void)
{
      uda1341_volume = 57;
    uda1341_boost = 0;  //声音默认值
    wm8976_write_reg(0,0);  //复位
  
    wm8976_write_reg(0x3, 0x6f);
    
    wm8976_write_reg(0x1, 0x1f);//biasen,BUFIOEN.VMIDSEL=11b  
    wm8976_write_reg(0x2, 0x185);//ROUT1EN LOUT1EN, inpu PGA enable ,ADC enable

    wm8976_write_reg(0x6, 0x0);//SYSCLK=MCLK  
    wm8976_write_reg(0x4, 0x10);//16bit         
    wm8976_write_reg(0x2B,0x10);//BTL OUTPUT  
    wm8976_write_reg(0x9, 0x50);//Jack detect enable  
    wm8976_write_reg(0xD, 0x21);//Jack detect  
    wm8976_write_reg(0x7, 0x01);//Jack detect 

}




static void init_s3c2410_iis_bus(void){
    __raw_writel(0, iis_base + S3C2410_IISPSR);
    __raw_writel(0, iis_base + S3C2410_IISCON);
    __raw_writel(0, iis_base + S3C2410_IISMOD);
    __raw_writel(0, iis_base + S3C2410_IISFCON);
    clk_disable(iis_clock);
}
static void init_s3c2410_iis_bus_rx(void){
    unsigned int iiscon, iismod, iisfcon;
    char *dstr;
//Kill everything...
    __raw_writel(0, iis_base + S3C2410_IISPSR);
    __raw_writel(0, iis_base + S3C2410_IISCON);
    __raw_writel(0, iis_base + S3C2410_IISMOD);
    __raw_writel(0, iis_base + S3C2410_IISFCON);

    clk_enable(iis_clock);

    iiscon = iismod = iisfcon = 0;

//Setup basic stuff
    iiscon |= S3C2410_IISCON_PSCEN; // Enable prescaler
    iiscon |= S3C2410_IISCON_IISEN; // Enable interface

//    iismod |= S3C2410_IISMOD_MASTER; // Set interface to Master Mode
    iismod |= S3C2410_IISMOD_LR_LLOW; // Low for left channel
    iismod |= S3C2410_IISMOD_MSB; // IIS format
    iismod |= S3C2410_IISMOD_16BIT; // Serial data bit/channel is 16 bit
    iismod |= S3C2410_IISMOD_384FS; // Master clock freq = 384 fs
    iismod |= S3C2410_IISMOD_32FS; // 32 fs

    iisfcon |= S3C2410_IISFCON_RXDMA; //Set RX FIFO acces mode to DMA
    iisfcon |= S3C2410_IISFCON_TXDMA; //Set RX FIFO acces mode to DMA

    iiscon |= S3C2410_IISCON_RXDMAEN; //Enable RX DMA service request
    iiscon |= S3C2410_IISCON_TXIDLE; //Set TX channel idle
    iismod |= S3C2410_IISMOD_RXMODE; //Set RX Mode
    iisfcon |= S3C2410_IISFCON_RXENABLE; //Enable RX Fifo
    dstr="RX";
//setup the prescaler
    audio_set_dsp_speed(audio_rate);

//iiscon has to be set last - it enables the interface
    __raw_writel(iismod, iis_base + S3C2410_IISMOD);
    __raw_writel(iisfcon, iis_base + S3C2410_IISFCON);
    __raw_writel(iiscon, iis_base + S3C2410_IISCON);
}

static void init_s3c2410_iis_bus_tx(void)
{
    unsigned int iiscon, iismod, iisfcon;
    char *dstr;

//Kill everything...
    __raw_writel(0, iis_base + S3C2410_IISPSR);
    __raw_writel(0, iis_base + S3C2410_IISCON);
    __raw_writel(0, iis_base + S3C2410_IISMOD);
    __raw_writel(0, iis_base + S3C2410_IISFCON);

    clk_enable(iis_clock);


    iiscon = iismod = iisfcon = 0;

//Setup basic stuff
    iiscon |= S3C2410_IISCON_PSCEN; // Enable prescaler
    iiscon |= S3C2410_IISCON_IISEN; // Enable interface

//    iismod |= S3C2410_IISMOD_MASTER; // Set interface to Master Mode
    iismod |= S3C2410_IISMOD_LR_LLOW; // Low for left channel
    iismod |= S3C2410_IISMOD_MSB; // MSB format
    iismod |= S3C2410_IISMOD_16BIT; // Serial data bit/channel is 16 bit
    iismod |= S3C2410_IISMOD_384FS; // Master clock freq = 384 fs
    iismod |= S3C2410_IISMOD_32FS; // 32 fs

    iisfcon|= S3C2410_IISFCON_RXDMA; //Set RX FIFO acces mode to DMA
    iisfcon|= S3C2410_IISFCON_TXDMA; //Set TX FIFO acces mode to DMA

    iiscon |= S3C2410_IISCON_TXDMAEN; //Enable TX DMA service request
    iiscon |= S3C2410_IISCON_RXIDLE; //Set RX channel idle
    iismod |= S3C2410_IISMOD_TXMODE; //Set TX Mode
    iisfcon|= S3C2410_IISFCON_TXENABLE; //Enable TX Fifo
    dstr="TX";

//setup the prescaler
    audio_set_dsp_speed(audio_rate);


//iiscon has to be set last - it enables the interface
    __raw_writel(iismod, iis_base + S3C2410_IISMOD);
    __raw_writel(iisfcon, iis_base + S3C2410_IISFCON);
    __raw_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;
    dmach_t channel;
    int dcon;
    unsigned int flags = 0;

    if(s->dma_ch == DMACH_I2S_OUT){
        channel = DMACH_I2S_OUT;
        source  = S3C2410_DMASRC_MEM;
        hwcfg   = BUF_ON_APB;
        devaddr = 0x55000010;
        dcon    = S3C2410_DCON_HANDSHAKE|S3C2410_DCON_SYNC_PCLK|S3C2410_DCON_INTREQ|S3C2410_DCON_TSZUNIT|S3C2410_DCON_SSERVE|S3C2410_DCON_CH2_I2SSDO|S3C2410_DCON_HWTRIG; // VAL: 0xa0800000;
        flags   = S3C2410_DMAF_AUTOSTART;

        ret = s3c2410_dma_request(s->dma_ch, &s3c2410iis_dma_out, NULL);
        s3c2410_dma_devconfig(channel, source, hwcfg, devaddr);
        s3c2410_dma_config(channel, 2, dcon);
        s3c2410_dma_set_buffdone_fn(channel, audio_dmaout_done_callback);
        s3c2410_dma_setflags(channel, flags);
        s->dma_ok = 1;
        return ret;
    }
    else if(s->dma_ch == DMACH_I2S_IN){
        channel = DMACH_I2S_IN;
        source  = S3C2410_DMASRC_HW;
        hwcfg   = BUF_ON_APB;
        devaddr = 0x55000010;
        dcon    = S3C2410_DCON_HANDSHAKE|S3C2410_DCON_SYNC_PCLK|S3C2410_DCON_INTREQ|S3C2410_DCON_TSZUNIT|S3C2410_DCON_SSERVE|S3C2410_DCON_CH1_I2SSDI|S3C2410_DCON_HWTRIG; // VAL: 0xa2800000;
        flags   = S3C2410_DMAF_AUTOSTART;

        ret = s3c2410_dma_request(s->dma_ch, &s3c2410iis_dma_in, NULL);
        s3c2410_dma_devconfig(channel, source, hwcfg, devaddr);
        s3c2410_dma_config(channel, 2, dcon);
        s3c2410_dma_set_buffdone_fn(channel, audio_dmain_done_callback);
        s3c2410_dma_setflags(channel, flags);
        s->dma_ok =1;
        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->dma_ch, NULL);
    s3c2410_dma_free(s->dma_ch, client);
    return 0;
}

static int s3c2410iis_probe(struct device *dev) 
{
    struct platform_device *pdev = to_platform_device(dev);
    struct resource *res;
    unsigned long flags;

    printk ("s3c2410iis_probe...
");
    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (res == NULL) {
        printk(KERN_INFO PFX "failed to get memory region resouce
");
        return -ENOENT;
    }

    iis_base = (void *)S3C24XX_VA_IIS ;
    if (iis_base == 0) {
        printk(KERN_INFO PFX "failed to ioremap() region
");
        return -EINVAL;
    }

    iis_clock = clk_get(dev, "iis");
    if (iis_clock == NULL) {
        printk(KERN_INFO PFX "failed to find clock source
");
        return -ENOENT;
    }

    clk_enable(iis_clock);               //使能IIS控制器时钟

    local_irq_save(flags);
    
    /* GPB 4: L3CLOCK, OUTPUT */
    s3c2410_gpio_cfgpin(S3C2410_GPB4, S3C2410_GPB4_OUTP);          // L3CLOCK
    s3c2410_gpio_pullup(S3C2410_GPB4,1);
    /* GPB 3: L3DATA, OUTPUT */
    s3c2410_gpio_cfgpin(S3C2410_GPB3,S3C2410_GPB3_OUTP);           // L3DATA
    /* GPB 2: L3MODE, OUTPUT */
    s3c2410_gpio_cfgpin(S3C2410_GPB2,S3C2410_GPB2_OUTP);            // L3MODE
    s3c2410_gpio_pullup(S3C2410_GPB2,1);
    /* GPE 3: I2SSDI */ 
    s3c2410_gpio_cfgpin(S3C2410_GPE3,S3C2410_GPE3_I2SSDI);         //  I2SSDI
    s3c2410_gpio_pullup(S3C2410_GPE3,0);
    /* GPE 0: I2SLRCK */
    s3c2410_gpio_cfgpin(S3C2410_GPE0,S3C2410_GPE0_I2SLRCK);         //  I2SLRCK
    s3c2410_gpio_pullup(S3C2410_GPE0,0);
    /* GPE 1: I2SSCLK */
    s3c2410_gpio_cfgpin(S3C2410_GPE1,S3C2410_GPE1_I2SSCLK);          //  I2SSCLK   IIS数据传输时钟
    s3c2410_gpio_pullup(S3C2410_GPE1,0);
    /* GPE 2: CDCLK */
    s3c2410_gpio_cfgpin(S3C2410_GPE2,S3C2410_GPE2_CDCLK);            //   CDCLK    wm8976芯片工作时钟
    s3c2410_gpio_pullup(S3C2410_GPE2,0);
    /* GPE 4: I2SSDO */
    s3c2410_gpio_cfgpin(S3C2410_GPE4,S3C2410_GPE4_I2SSDO);           //  I2SSDO
    s3c2410_gpio_pullup(S3C2410_GPE4,0);

    local_irq_restore(flags);

    init_s3c2410_iis_bus();              //设置IIS控制器

    init_wm8976();         //使用L3接口初始化 wm8976 芯片

    output_stream.dma_ch = DMACH_I2S_OUT;                   // 设置DMA通道,用于播放
    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
" );
        return -EBUSY;
    }
    
    input_stream.dma_ch = DMACH_I2S_IN;                    // 设置DMA通道,用于录音
    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
" );
        return -EBUSY;
    }

    audio_dev_dsp = register_sound_dsp(&smdk2410_audio_fops, -1);    //注册字符设备 dsp       /dev/dsp  播音/录音
    audio_dev_mixer = register_sound_mixer(&smdk2410_mixer_fops, -1);   //注册字符设备 mixer  /dev/mixer         音量 
 
    printk(AUDIO_NAME_VERBOSE " initialized
"); 

    return 0;
}


static int s3c2410iis_remove(struct 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
");
    return 0;
}

extern struct bus_type platform_bus_type;
static struct device_driver s3c2410iis_driver = {
    .name = "s3c2410-iis",
    .bus = &platform_bus_type,
    .probe = s3c2410iis_probe,
    .remove = s3c2410iis_remove,
};

static int __init s3c2410_uda1341_init(void) {
    memzero(&input_stream, sizeof(audio_stream_t));
    memzero(&output_stream, sizeof(audio_stream_t));
    return driver_register(&s3c2410iis_driver);
}

static void __exit s3c2410_uda1341_exit(void) {
    driver_unregister(&s3c2410iis_driver);
}

module_init(s3c2410_uda1341_init);
module_exit(s3c2410_uda1341_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("superlp<[email protected]>");
MODULE_DESCRIPTION("S3C2410 uda1341 sound driver");

 



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