es1968.c

linux 内核源代码

	spin_lock(&chip->reg_lock);
	__apu_set_register(chip, es->apu[0], 5, es->base[0]);
	snd_es1968_trigger_apu(chip, es->apu[0], es->apu_mode[0]);
	if (es->mode == ESM_MODE_CAPTURE) {
		__apu_set_register(chip, es->apu[2], 5, es->base[2]);
		snd_es1968_trigger_apu(chip, es->apu[2], es->apu_mode[2]);
	}
	if (es->fmt & ESS_FMT_STEREO) {
		__apu_set_register(chip, es->apu[1], 5, es->base[1]);
		snd_es1968_trigger_apu(chip, es->apu[1], es->apu_mode[1]);
		if (es->mode == ESM_MODE_CAPTURE) {
			__apu_set_register(chip, es->apu[3], 5, es->base[3]);
			snd_es1968_trigger_apu(chip, es->apu[3], es->apu_mode[3]);
		}
	}
	spin_unlock(&chip->reg_lock);
}

static void snd_es1968_pcm_stop(struct es1968 *chip, struct esschan *es)
{
	spin_lock(&chip->reg_lock);
	snd_es1968_trigger_apu(chip, es->apu[0], 0);
	snd_es1968_trigger_apu(chip, es->apu[1], 0);
	if (es->mode == ESM_MODE_CAPTURE) {
		snd_es1968_trigger_apu(chip, es->apu[2], 0);
		snd_es1968_trigger_apu(chip, es->apu[3], 0);
	}
	spin_unlock(&chip->reg_lock);
}

/* set the wavecache control reg */
static void snd_es1968_program_wavecache(struct es1968 *chip, struct esschan *es,
					 int channel, u32 addr, int capture)
{
	u32 tmpval = (addr - 0x10) & 0xFFF8;

	if (! capture) {
		if (!(es->fmt & ESS_FMT_16BIT))
			tmpval |= 4;	/* 8bit */
		if (es->fmt & ESS_FMT_STEREO)
			tmpval |= 2;	/* stereo */
	}

	/* set the wavecache control reg */
	wave_set_register(chip, es->apu[channel] << 3, tmpval);

#ifdef CONFIG_PM
	es->wc_map[channel] = tmpval;
#endif
}


static void snd_es1968_playback_setup(struct es1968 *chip, struct esschan *es,
				      struct snd_pcm_runtime *runtime)
{
	u32 pa;
	int high_apu = 0;
	int channel, apu;
	int i, size;
	unsigned long flags;
	u32 freq;

	size = es->dma_size >> es->wav_shift;

	if (es->fmt & ESS_FMT_STEREO)
		high_apu++;

	for (channel = 0; channel <= high_apu; channel++) {
		apu = es->apu[channel];

		snd_es1968_program_wavecache(chip, es, channel, es->memory->buf.addr, 0);

		/* Offset to PCMBAR */
		pa = es->memory->buf.addr;
		pa -= chip->dma.addr;
		pa >>= 1;	/* words */

		pa |= 0x00400000;	/* System RAM (Bit 22) */

		if (es->fmt & ESS_FMT_STEREO) {
			/* Enable stereo */
			if (channel)
				pa |= 0x00800000;	/* (Bit 23) */
			if (es->fmt & ESS_FMT_16BIT)
				pa >>= 1;
		}

		/* base offset of dma calcs when reading the pointer
		   on this left one */
		es->base[channel] = pa & 0xFFFF;

		for (i = 0; i < 16; i++)
			apu_set_register(chip, apu, i, 0x0000);

		/* Load the buffer into the wave engine */
		apu_set_register(chip, apu, 4, ((pa >> 16) & 0xFF) << 8);
		apu_set_register(chip, apu, 5, pa & 0xFFFF);
		apu_set_register(chip, apu, 6, (pa + size) & 0xFFFF);
		/* setting loop == sample len */
		apu_set_register(chip, apu, 7, size);

		/* clear effects/env.. */
		apu_set_register(chip, apu, 8, 0x0000);
		/* set amp now to 0xd0 (?), low byte is 'amplitude dest'? */
		apu_set_register(chip, apu, 9, 0xD000);

		/* clear routing stuff */
		apu_set_register(chip, apu, 11, 0x0000);
		/* dma on, no envelopes, filter to all 1s) */
		apu_set_register(chip, apu, 0, 0x400F);

		if (es->fmt & ESS_FMT_16BIT)
			es->apu_mode[channel] = ESM_APU_16BITLINEAR;
		else
			es->apu_mode[channel] = ESM_APU_8BITLINEAR;

		if (es->fmt & ESS_FMT_STEREO) {
			/* set panning: left or right */
			/* Check: different panning. On my Canyon 3D Chipset the
			   Channels are swapped. I don't know, about the output
			   to the SPDif Link. Perhaps you have to change this
			   and not the APU Regs 4-5. */
			apu_set_register(chip, apu, 10,
					 0x8F00 | (channel ? 0 : 0x10));
			es->apu_mode[channel] += 1;	/* stereo */
		} else
			apu_set_register(chip, apu, 10, 0x8F08);
	}

	spin_lock_irqsave(&chip->reg_lock, flags);
	/* clear WP interrupts */
	outw(1, chip->io_port + 0x04);
	/* enable WP ints */
	outw(inw(chip->io_port + ESM_PORT_HOST_IRQ) | ESM_HIRQ_DSIE, chip->io_port + ESM_PORT_HOST_IRQ);
	spin_unlock_irqrestore(&chip->reg_lock, flags);

	freq = runtime->rate;
	/* set frequency */
	if (freq > 48000)
		freq = 48000;
	if (freq < 4000)
		freq = 4000;

	/* hmmm.. */
	if (!(es->fmt & ESS_FMT_16BIT) && !(es->fmt & ESS_FMT_STEREO))
		freq >>= 1;

	freq = snd_es1968_compute_rate(chip, freq);

	/* Load the frequency, turn on 6dB */
	snd_es1968_apu_set_freq(chip, es->apu[0], freq);
	snd_es1968_apu_set_freq(chip, es->apu[1], freq);
}


static void init_capture_apu(struct es1968 *chip, struct esschan *es, int channel,
			     unsigned int pa, unsigned int bsize,
			     int mode, int route)
{
	int i, apu = es->apu[channel];

	es->apu_mode[channel] = mode;

	/* set the wavecache control reg */
	snd_es1968_program_wavecache(chip, es, channel, pa, 1);

	/* Offset to PCMBAR */
	pa -= chip->dma.addr;
	pa >>= 1;	/* words */

	/* base offset of dma calcs when reading the pointer
	   on this left one */
	es->base[channel] = pa & 0xFFFF;
	pa |= 0x00400000;	/* bit 22 -> System RAM */

	/* Begin loading the APU */
	for (i = 0; i < 16; i++)
		apu_set_register(chip, apu, i, 0x0000);

	/* need to enable subgroups.. and we should probably
	   have different groups for different /dev/dsps..  */
	apu_set_register(chip, apu, 2, 0x8);

	/* Load the buffer into the wave engine */
	apu_set_register(chip, apu, 4, ((pa >> 16) & 0xFF) << 8);
	apu_set_register(chip, apu, 5, pa & 0xFFFF);
	apu_set_register(chip, apu, 6, (pa + bsize) & 0xFFFF);
	apu_set_register(chip, apu, 7, bsize);
	/* clear effects/env.. */
	apu_set_register(chip, apu, 8, 0x00F0);
	/* amplitude now?  sure.  why not.  */
	apu_set_register(chip, apu, 9, 0x0000);
	/* set filter tune, radius, polar pan */
	apu_set_register(chip, apu, 10, 0x8F08);
	/* route input */
	apu_set_register(chip, apu, 11, route);
	/* dma on, no envelopes, filter to all 1s) */
	apu_set_register(chip, apu, 0, 0x400F);
}

static void snd_es1968_capture_setup(struct es1968 *chip, struct esschan *es,
				     struct snd_pcm_runtime *runtime)
{
	int size;
	u32 freq;
	unsigned long flags;

	size = es->dma_size >> es->wav_shift;

	/* APU assignments:
	   0 = mono/left SRC
	   1 = right SRC
	   2 = mono/left Input Mixer
	   3 = right Input Mixer
	*/
	/* data seems to flow from the codec, through an apu into
	   the 'mixbuf' bit of page, then through the SRC apu
	   and out to the real 'buffer'.  ok.  sure.  */

	/* input mixer (left/mono) */
	/* parallel in crap, see maestro reg 0xC [8-11] */
	init_capture_apu(chip, es, 2,
			 es->mixbuf->buf.addr, ESM_MIXBUF_SIZE/4, /* in words */
			 ESM_APU_INPUTMIXER, 0x14);
	/* SRC (left/mono); get input from inputing apu */
	init_capture_apu(chip, es, 0, es->memory->buf.addr, size,
			 ESM_APU_SRCONVERTOR, es->apu[2]);
	if (es->fmt & ESS_FMT_STEREO) {
		/* input mixer (right) */
		init_capture_apu(chip, es, 3,
				 es->mixbuf->buf.addr + ESM_MIXBUF_SIZE/2,
				 ESM_MIXBUF_SIZE/4, /* in words */
				 ESM_APU_INPUTMIXER, 0x15);
		/* SRC (right) */
		init_capture_apu(chip, es, 1,
				 es->memory->buf.addr + size*2, size,
				 ESM_APU_SRCONVERTOR, es->apu[3]);
	}

	freq = runtime->rate;
	/* Sample Rate conversion APUs don't like 0x10000 for their rate */
	if (freq > 47999)
		freq = 47999;
	if (freq < 4000)
		freq = 4000;

	freq = snd_es1968_compute_rate(chip, freq);

	/* Load the frequency, turn on 6dB */
	snd_es1968_apu_set_freq(chip, es->apu[0], freq);
	snd_es1968_apu_set_freq(chip, es->apu[1], freq);

	/* fix mixer rate at 48khz.  and its _must_ be 0x10000. */
	freq = 0x10000;
	snd_es1968_apu_set_freq(chip, es->apu[2], freq);
	snd_es1968_apu_set_freq(chip, es->apu[3], freq);

	spin_lock_irqsave(&chip->reg_lock, flags);
	/* clear WP interrupts */
	outw(1, chip->io_port + 0x04);
	/* enable WP ints */
	outw(inw(chip->io_port + ESM_PORT_HOST_IRQ) | ESM_HIRQ_DSIE, chip->io_port + ESM_PORT_HOST_IRQ);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
}

/*******************
 *  ALSA Interface *
 *******************/

static int snd_es1968_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct esschan *es = runtime->private_data;

	es->dma_size = snd_pcm_lib_buffer_bytes(substream);
	es->frag_size = snd_pcm_lib_period_bytes(substream);

	es->wav_shift = 1; /* maestro handles always 16bit */
	es->fmt = 0;
	if (snd_pcm_format_width(runtime->format) == 16)
		es->fmt |= ESS_FMT_16BIT;
	if (runtime->channels > 1) {
		es->fmt |= ESS_FMT_STEREO;
		if (es->fmt & ESS_FMT_16BIT) /* 8bit is already word shifted */
			es->wav_shift++;
	}
	es->bob_freq = snd_es1968_calc_bob_rate(chip, es, runtime);

	switch (es->mode) {
	case ESM_MODE_PLAY:
		snd_es1968_playback_setup(chip, es, runtime);
		break;
	case ESM_MODE_CAPTURE:
		snd_es1968_capture_setup(chip, es, runtime);
		break;
	}

	return 0;
}

static int snd_es1968_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct esschan *es = substream->runtime->private_data;

	spin_lock(&chip->substream_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		if (es->running)
			break;
		snd_es1968_bob_inc(chip, es->bob_freq);
		es->count = 0;
		es->hwptr = 0;
		snd_es1968_pcm_start(chip, es);
		es->running = 1;
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		if (! es->running)
			break;
		snd_es1968_pcm_stop(chip, es);
		es->running = 0;
		snd_es1968_bob_dec(chip);
		break;
	}
	spin_unlock(&chip->substream_lock);
	return 0;
}

static snd_pcm_uframes_t snd_es1968_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct esschan *es = substream->runtime->private_data;
	unsigned int ptr;

	ptr = snd_es1968_get_dma_ptr(chip, es) << es->wav_shift;
	
	return bytes_to_frames(substream->runtime, ptr % es->dma_size);
}

static struct snd_pcm_hardware snd_es1968_playback = {
	.info =			(SNDRV_PCM_INFO_MMAP |
               		         SNDRV_PCM_INFO_MMAP_VALID |
				 SNDRV_PCM_INFO_INTERLEAVED |
				 SNDRV_PCM_INFO_BLOCK_TRANSFER |
				 /*SNDRV_PCM_INFO_PAUSE |*/
				 SNDRV_PCM_INFO_RESUME),
	.formats =		SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
	.rate_min =		4000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.buffer_bytes_max =	65536,
	.period_bytes_min =	256,
	.period_bytes_max =	65536,
	.periods_min =		1,
	.periods_max =		1024,
	.fifo_size =		0,
};

static struct snd_pcm_hardware snd_es1968_capture = {
	.info =			(SNDRV_PCM_INFO_NONINTERLEAVED |
				 SNDRV_PCM_INFO_MMAP |
				 SNDRV_PCM_INFO_MMAP_VALID |
				 SNDRV_PCM_INFO_BLOCK_TRANSFER |
				 /*SNDRV_PCM_INFO_PAUSE |*/
				 SNDRV_PCM_INFO_RESUME),
	.formats =		/*SNDRV_PCM_FMTBIT_U8 |*/ SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
	.rate_min =		4000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.buffer_bytes_max =	65536,
	.period_bytes_min =	256,
	.period_bytes_max =	65536,
	.periods_min =		1,
	.periods_max =		1024,
	.fifo_size =		0,
};

/* *************************
   * DMA memory management *
   *************************/

/* Because the Maestro can only take addresses relative to the PCM base address
   register :( */

static int calc_available_memory_size(struct es1968 *chip)
{
	int max_size = 0;
	struct esm_memory *buf;

	mutex_lock(&chip->memory_mutex);
	list_for_each_entry(buf, &chip->buf_list, list) {
		if (buf->empty && buf->buf.bytes > max_size)
			max_size = buf->buf.bytes;
	}
	mutex_unlock(&chip->memory_mutex);
	if (max_size >= 128*1024)
		max_size = 127*1024;
	return max_size;
}

/* allocate a new memory chunk with the specified size */
static struct esm_memory *snd_es1968_new_memory(struct es1968 *chip, int size)
{
	struct esm_memory *buf;

	size = ALIGN(size, ESM_MEM_ALIGN);
	mutex_lock(&chip->memory_mutex);
	list_for_each_entry(buf, &chip->buf_list, list) {
		if (buf->empty && buf->buf.bytes >= size)
			goto __found;
	}
	mutex_unlock(&chip->memory_mutex);
	return NULL;

__found:
	if (buf->buf.bytes > size) {
		struct esm_memory *chunk = kmalloc(sizeof(*chunk), GFP_KERNEL);
		if (chunk == NULL) {
			mutex_unlock(&chip->memory_mutex);
			return NULL;
		}
		chunk->buf = buf->buf;
		chunk->buf.bytes -= size;
		chunk->buf.area += size;
		chunk->buf.addr += size;
		chunk->empty = 1;
		buf->buf.bytes = size;
		list_add(&chunk->list, &buf->list);
	}
	buf->empty = 0;
	mutex_unlock(&chip->memory_mutex);
	return buf;
}

/* free a memory chunk */
static void snd_es1968_free_memory(struct es1968 *chip, struct esm_memory *buf)
{
	struct esm_memory *chunk;

	mutex_lock(&chip->memory_mutex);
	buf->empty = 1;
	if (buf->list.prev != &chip->buf_list) {
		chunk = list_entry(buf->list.prev, struct esm_memory, list);
		if (chunk->empty) {
			chunk->buf.bytes += buf->buf.bytes;
			list_del(&buf->list);
			kfree(buf);
			buf = chunk;
		}
	}
	if (buf->list.next != &chip->buf_list) {
		chunk = list_entry(buf->list.next, struct esm_memory, list);
		if (chunk->empty) {
			buf->buf.bytes += chunk->buf.bytes;
			list_del(&chunk->list);