amd7930.c

linux 内核源代码

	sbus_writeb(AMR_MAP_GX, amd->regs + AMD7930_CR);
	sbus_writeb(((map->gx >> 0) & 0xff), amd->regs + AMD7930_DR);
	sbus_writeb(((map->gx >> 8) & 0xff), amd->regs + AMD7930_DR);

	sbus_writeb(AMR_MAP_GR, amd->regs + AMD7930_CR);
	sbus_writeb(((map->gr >> 0) & 0xff), amd->regs + AMD7930_DR);
	sbus_writeb(((map->gr >> 8) & 0xff), amd->regs + AMD7930_DR);

	sbus_writeb(AMR_MAP_STGR, amd->regs + AMD7930_CR);
	sbus_writeb(((map->stgr >> 0) & 0xff), amd->regs + AMD7930_DR);
	sbus_writeb(((map->stgr >> 8) & 0xff), amd->regs + AMD7930_DR);

	sbus_writeb(AMR_MAP_GER, amd->regs + AMD7930_CR);
	sbus_writeb(((map->ger >> 0) & 0xff), amd->regs + AMD7930_DR);
	sbus_writeb(((map->ger >> 8) & 0xff), amd->regs + AMD7930_DR);

	sbus_writeb(AMR_MAP_MMR1, amd->regs + AMD7930_CR);
	sbus_writeb(map->mmr1, amd->regs + AMD7930_DR);

	sbus_writeb(AMR_MAP_MMR2, amd->regs + AMD7930_CR);
	sbus_writeb(map->mmr2, amd->regs + AMD7930_DR);
}

/* gx, gr & stg gains.  this table must contain 256 elements with
 * the 0th being "infinity" (the magic value 9008).  The remaining
 * elements match sun's gain curve (but with higher resolution):
 * -18 to 0dB in .16dB steps then 0 to 12dB in .08dB steps.
 */
static __const__ __u16 gx_coeff[256] = {
	0x9008, 0x8b7c, 0x8b51, 0x8b45, 0x8b42, 0x8b3b, 0x8b36, 0x8b33,
	0x8b32, 0x8b2a, 0x8b2b, 0x8b2c, 0x8b25, 0x8b23, 0x8b22, 0x8b22,
	0x9122, 0x8b1a, 0x8aa3, 0x8aa3, 0x8b1c, 0x8aa6, 0x912d, 0x912b,
	0x8aab, 0x8b12, 0x8aaa, 0x8ab2, 0x9132, 0x8ab4, 0x913c, 0x8abb,
	0x9142, 0x9144, 0x9151, 0x8ad5, 0x8aeb, 0x8a79, 0x8a5a, 0x8a4a,
	0x8b03, 0x91c2, 0x91bb, 0x8a3f, 0x8a33, 0x91b2, 0x9212, 0x9213,
	0x8a2c, 0x921d, 0x8a23, 0x921a, 0x9222, 0x9223, 0x922d, 0x9231,
	0x9234, 0x9242, 0x925b, 0x92dd, 0x92c1, 0x92b3, 0x92ab, 0x92a4,
	0x92a2, 0x932b, 0x9341, 0x93d3, 0x93b2, 0x93a2, 0x943c, 0x94b2,
	0x953a, 0x9653, 0x9782, 0x9e21, 0x9d23, 0x9cd2, 0x9c23, 0x9baa,
	0x9bde, 0x9b33, 0x9b22, 0x9b1d, 0x9ab2, 0xa142, 0xa1e5, 0x9a3b,
	0xa213, 0xa1a2, 0xa231, 0xa2eb, 0xa313, 0xa334, 0xa421, 0xa54b,
	0xada4, 0xac23, 0xab3b, 0xaaab, 0xaa5c, 0xb1a3, 0xb2ca, 0xb3bd,
	0xbe24, 0xbb2b, 0xba33, 0xc32b, 0xcb5a, 0xd2a2, 0xe31d, 0x0808,
	0x72ba, 0x62c2, 0x5c32, 0x52db, 0x513e, 0x4cce, 0x43b2, 0x4243,
	0x41b4, 0x3b12, 0x3bc3, 0x3df2, 0x34bd, 0x3334, 0x32c2, 0x3224,
	0x31aa, 0x2a7b, 0x2aaa, 0x2b23, 0x2bba, 0x2c42, 0x2e23, 0x25bb,
	0x242b, 0x240f, 0x231a, 0x22bb, 0x2241, 0x2223, 0x221f, 0x1a33,
	0x1a4a, 0x1acd, 0x2132, 0x1b1b, 0x1b2c, 0x1b62, 0x1c12, 0x1c32,
	0x1d1b, 0x1e71, 0x16b1, 0x1522, 0x1434, 0x1412, 0x1352, 0x1323,
	0x1315, 0x12bc, 0x127a, 0x1235, 0x1226, 0x11a2, 0x1216, 0x0a2a,
	0x11bc, 0x11d1, 0x1163, 0x0ac2, 0x0ab2, 0x0aab, 0x0b1b, 0x0b23,
	0x0b33, 0x0c0f, 0x0bb3, 0x0c1b, 0x0c3e, 0x0cb1, 0x0d4c, 0x0ec1,
	0x079a, 0x0614, 0x0521, 0x047c, 0x0422, 0x03b1, 0x03e3, 0x0333,
	0x0322, 0x031c, 0x02aa, 0x02ba, 0x02f2, 0x0242, 0x0232, 0x0227,
	0x0222, 0x021b, 0x01ad, 0x0212, 0x01b2, 0x01bb, 0x01cb, 0x01f6,
	0x0152, 0x013a, 0x0133, 0x0131, 0x012c, 0x0123, 0x0122, 0x00a2,
	0x011b, 0x011e, 0x0114, 0x00b1, 0x00aa, 0x00b3, 0x00bd, 0x00ba,
	0x00c5, 0x00d3, 0x00f3, 0x0062, 0x0051, 0x0042, 0x003b, 0x0033,
	0x0032, 0x002a, 0x002c, 0x0025, 0x0023, 0x0022, 0x001a, 0x0021,
	0x001b, 0x001b, 0x001d, 0x0015, 0x0013, 0x0013, 0x0012, 0x0012,
	0x000a, 0x000a, 0x0011, 0x0011, 0x000b, 0x000b, 0x000c, 0x000e,
};

static __const__ __u16 ger_coeff[] = {
	0x431f, /* 5. dB */
	0x331f, /* 5.5 dB */
	0x40dd, /* 6. dB */
	0x11dd, /* 6.5 dB */
	0x440f, /* 7. dB */
	0x411f, /* 7.5 dB */
	0x311f, /* 8. dB */
	0x5520, /* 8.5 dB */
	0x10dd, /* 9. dB */
	0x4211, /* 9.5 dB */
	0x410f, /* 10. dB */
	0x111f, /* 10.5 dB */
	0x600b, /* 11. dB */
	0x00dd, /* 11.5 dB */
	0x4210, /* 12. dB */
	0x110f, /* 13. dB */
	0x7200, /* 14. dB */
	0x2110, /* 15. dB */
	0x2200, /* 15.9 dB */
	0x000b, /* 16.9 dB */
	0x000f  /* 18. dB */
};

/* Update amd7930_map settings and program them into the hardware.
 * The amd->lock is held and local interrupts are disabled.
 */
static void __amd7930_update_map(struct snd_amd7930 *amd)
{
	struct amd7930_map *map = &amd->map;
	int level;

	map->gx = gx_coeff[amd->rgain];
	map->stgr = gx_coeff[amd->mgain];
	level = (amd->pgain * (256 + ARRAY_SIZE(ger_coeff))) >> 8;
	if (level >= 256) {
		map->ger = ger_coeff[level - 256];
		map->gr = gx_coeff[255];
	} else {
		map->ger = ger_coeff[0];
		map->gr = gx_coeff[level];
	}
	__amd7930_write_map(amd);
}

static irqreturn_t snd_amd7930_interrupt(int irq, void *dev_id)
{
	struct snd_amd7930 *amd = dev_id;
	unsigned int elapsed;
	u8 ir;

	spin_lock(&amd->lock);

	elapsed = 0;

	ir = sbus_readb(amd->regs + AMD7930_IR);
	if (ir & AMR_IR_BBUF) {
		u8 byte;

		if (amd->flags & AMD7930_FLAG_PLAYBACK) {
			if (amd->p_left > 0) {
				byte = *(amd->p_cur++);
				amd->p_left--;
				sbus_writeb(byte, amd->regs + AMD7930_BBTB);
				if (amd->p_left == 0)
					elapsed |= AMD7930_FLAG_PLAYBACK;
			} else
				sbus_writeb(0, amd->regs + AMD7930_BBTB);
		} else if (amd->flags & AMD7930_FLAG_CAPTURE) {
			byte = sbus_readb(amd->regs + AMD7930_BBRB);
			if (amd->c_left > 0) {
				*(amd->c_cur++) = byte;
				amd->c_left--;
				if (amd->c_left == 0)
					elapsed |= AMD7930_FLAG_CAPTURE;
			}
		}
	}
	spin_unlock(&amd->lock);

	if (elapsed & AMD7930_FLAG_PLAYBACK)
		snd_pcm_period_elapsed(amd->playback_substream);
	else
		snd_pcm_period_elapsed(amd->capture_substream);

	return IRQ_HANDLED;
}

static int snd_amd7930_trigger(struct snd_amd7930 *amd, unsigned int flag, int cmd)
{
	unsigned long flags;
	int result = 0;

	spin_lock_irqsave(&amd->lock, flags);
	if (cmd == SNDRV_PCM_TRIGGER_START) {
		if (!(amd->flags & flag)) {
			amd->flags |= flag;

			/* Enable B channel interrupts.  */
			sbus_writeb(AMR_MUX_MCR4, amd->regs + AMD7930_CR);
			sbus_writeb(AM_MUX_MCR4_ENABLE_INTS, amd->regs + AMD7930_DR);
		}
	} else if (cmd == SNDRV_PCM_TRIGGER_STOP) {
		if (amd->flags & flag) {
			amd->flags &= ~flag;

			/* Disable B channel interrupts.  */
			sbus_writeb(AMR_MUX_MCR4, amd->regs + AMD7930_CR);
			sbus_writeb(0, amd->regs + AMD7930_DR);
		}
	} else {
		result = -EINVAL;
	}
	spin_unlock_irqrestore(&amd->lock, flags);

	return result;
}

static int snd_amd7930_playback_trigger(struct snd_pcm_substream *substream,
					int cmd)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	return snd_amd7930_trigger(amd, AMD7930_FLAG_PLAYBACK, cmd);
}

static int snd_amd7930_capture_trigger(struct snd_pcm_substream *substream,
				       int cmd)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	return snd_amd7930_trigger(amd, AMD7930_FLAG_CAPTURE, cmd);
}

static int snd_amd7930_playback_prepare(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	unsigned int size = snd_pcm_lib_buffer_bytes(substream);
	unsigned long flags;
	u8 new_mmr1;

	spin_lock_irqsave(&amd->lock, flags);

	amd->flags |= AMD7930_FLAG_PLAYBACK;

	/* Setup the pseudo-dma transfer pointers.  */
	amd->p_orig = amd->p_cur = runtime->dma_area;
	amd->p_left = size;

	/* Put the chip into the correct encoding format.  */
	new_mmr1 = amd->map.mmr1;
	if (runtime->format == SNDRV_PCM_FORMAT_A_LAW)
		new_mmr1 |= AM_MAP_MMR1_ALAW;
	else
		new_mmr1 &= ~AM_MAP_MMR1_ALAW;
	if (new_mmr1 != amd->map.mmr1) {
		amd->map.mmr1 = new_mmr1;
		__amd7930_update_map(amd);
	}

	spin_unlock_irqrestore(&amd->lock, flags);

	return 0;
}

static int snd_amd7930_capture_prepare(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	unsigned int size = snd_pcm_lib_buffer_bytes(substream);
	unsigned long flags;
	u8 new_mmr1;

	spin_lock_irqsave(&amd->lock, flags);

	amd->flags |= AMD7930_FLAG_CAPTURE;

	/* Setup the pseudo-dma transfer pointers.  */
	amd->c_orig = amd->c_cur = runtime->dma_area;
	amd->c_left = size;

	/* Put the chip into the correct encoding format.  */
	new_mmr1 = amd->map.mmr1;
	if (runtime->format == SNDRV_PCM_FORMAT_A_LAW)
		new_mmr1 |= AM_MAP_MMR1_ALAW;
	else
		new_mmr1 &= ~AM_MAP_MMR1_ALAW;
	if (new_mmr1 != amd->map.mmr1) {
		amd->map.mmr1 = new_mmr1;
		__amd7930_update_map(amd);
	}

	spin_unlock_irqrestore(&amd->lock, flags);

	return 0;
}

static snd_pcm_uframes_t snd_amd7930_playback_pointer(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	size_t ptr;

	if (!(amd->flags & AMD7930_FLAG_PLAYBACK))
		return 0;
	ptr = amd->p_cur - amd->p_orig;
	return bytes_to_frames(substream->runtime, ptr);
}

static snd_pcm_uframes_t snd_amd7930_capture_pointer(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	size_t ptr;

	if (!(amd->flags & AMD7930_FLAG_CAPTURE))
		return 0;

	ptr = amd->c_cur - amd->c_orig;
	return bytes_to_frames(substream->runtime, ptr);
}

/* Playback and capture have identical properties.  */
static struct snd_pcm_hardware snd_amd7930_pcm_hw =
{
	.info			= (SNDRV_PCM_INFO_MMAP |
				   SNDRV_PCM_INFO_MMAP_VALID |
				   SNDRV_PCM_INFO_INTERLEAVED |
				   SNDRV_PCM_INFO_BLOCK_TRANSFER |
				   SNDRV_PCM_INFO_HALF_DUPLEX),
	.formats		= SNDRV_PCM_FMTBIT_MU_LAW | SNDRV_PCM_FMTBIT_A_LAW,
	.rates			= SNDRV_PCM_RATE_8000,
	.rate_min		= 8000,
	.rate_max		= 8000,
	.channels_min		= 1,
	.channels_max		= 1,
	.buffer_bytes_max	= (64*1024),
	.period_bytes_min	= 1,
	.period_bytes_max	= (64*1024),
	.periods_min		= 1,
	.periods_max		= 1024,
};

static int snd_amd7930_playback_open(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;

	amd->playback_substream = substream;
	runtime->hw = snd_amd7930_pcm_hw;
	return 0;
}

static int snd_amd7930_capture_open(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;

	amd->capture_substream = substream;
	runtime->hw = snd_amd7930_pcm_hw;
	return 0;
}

static int snd_amd7930_playback_close(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);

	amd->playback_substream = NULL;
	return 0;
}

static int snd_amd7930_capture_close(struct snd_pcm_substream *substream)
{
	struct snd_amd7930 *amd = snd_pcm_substream_chip(substream);

	amd->capture_substream = NULL;
	return 0;
}

static int snd_amd7930_hw_params(struct snd_pcm_substream *substream,
				    struct snd_pcm_hw_params *hw_params)
{
	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
}

static int snd_amd7930_hw_free(struct snd_pcm_substream *substream)
{
	return snd_pcm_lib_free_pages(substream);
}

static struct snd_pcm_ops snd_amd7930_playback_ops = {
	.open		=	snd_amd7930_playback_open,
	.close		=	snd_amd7930_playback_close,
	.ioctl		=	snd_pcm_lib_ioctl,
	.hw_params	=	snd_amd7930_hw_params,
	.hw_free	=	snd_amd7930_hw_free,
	.prepare	=	snd_amd7930_playback_prepare,
	.trigger	=	snd_amd7930_playback_trigger,
	.pointer	=	snd_amd7930_playback_pointer,
};

static struct snd_pcm_ops snd_amd7930_capture_ops = {
	.open		=	snd_amd7930_capture_open,
	.close		=	snd_amd7930_capture_close,
	.ioctl		=	snd_pcm_lib_ioctl,
	.hw_params	=	snd_amd7930_hw_params,
	.hw_free	=	snd_amd7930_hw_free,
	.prepare	=	snd_amd7930_capture_prepare,
	.trigger	=	snd_amd7930_capture_trigger,
	.pointer	=	snd_amd7930_capture_pointer,
};

static int __devinit snd_amd7930_pcm(struct snd_amd7930 *amd)
{
	struct snd_pcm *pcm;
	int err;

	if ((err = snd_pcm_new(amd->card,
			       /* ID */             "sun_amd7930",
			       /* device */         0,
			       /* playback count */ 1,
			       /* capture count */  1, &pcm)) < 0)
		return err;
	snd_assert(pcm != NULL, return -EINVAL);