es1968.c

linux 内核源代码

			kfree(chunk);
		}
	}
	mutex_unlock(&chip->memory_mutex);
}

static void snd_es1968_free_dmabuf(struct es1968 *chip)
{
	struct list_head *p;

	if (! chip->dma.area)
		return;
	snd_dma_reserve_buf(&chip->dma, snd_dma_pci_buf_id(chip->pci));
	while ((p = chip->buf_list.next) != &chip->buf_list) {
		struct esm_memory *chunk = list_entry(p, struct esm_memory, list);
		list_del(p);
		kfree(chunk);
	}
}

static int __devinit
snd_es1968_init_dmabuf(struct es1968 *chip)
{
	int err;
	struct esm_memory *chunk;

	chip->dma.dev.type = SNDRV_DMA_TYPE_DEV;
	chip->dma.dev.dev = snd_dma_pci_data(chip->pci);
	if (! snd_dma_get_reserved_buf(&chip->dma, snd_dma_pci_buf_id(chip->pci))) {
		err = snd_dma_alloc_pages_fallback(SNDRV_DMA_TYPE_DEV,
						   snd_dma_pci_data(chip->pci),
						   chip->total_bufsize, &chip->dma);
		if (err < 0 || ! chip->dma.area) {
			snd_printk(KERN_ERR "es1968: can't allocate dma pages for size %d\n",
				   chip->total_bufsize);
			return -ENOMEM;
		}
		if ((chip->dma.addr + chip->dma.bytes - 1) & ~((1 << 28) - 1)) {
			snd_dma_free_pages(&chip->dma);
			snd_printk(KERN_ERR "es1968: DMA buffer beyond 256MB.\n");
			return -ENOMEM;
		}
	}

	INIT_LIST_HEAD(&chip->buf_list);
	/* allocate an empty chunk */
	chunk = kmalloc(sizeof(*chunk), GFP_KERNEL);
	if (chunk == NULL) {
		snd_es1968_free_dmabuf(chip);
		return -ENOMEM;
	}
	memset(chip->dma.area, 0, ESM_MEM_ALIGN);
	chunk->buf = chip->dma;
	chunk->buf.area += ESM_MEM_ALIGN;
	chunk->buf.addr += ESM_MEM_ALIGN;
	chunk->buf.bytes -= ESM_MEM_ALIGN;
	chunk->empty = 1;
	list_add(&chunk->list, &chip->buf_list);

	return 0;
}

/* setup the dma_areas */
/* buffer is extracted from the pre-allocated memory chunk */
static int snd_es1968_hw_params(struct snd_pcm_substream *substream,
				struct snd_pcm_hw_params *hw_params)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct esschan *chan = runtime->private_data;
	int size = params_buffer_bytes(hw_params);

	if (chan->memory) {
		if (chan->memory->buf.bytes >= size) {
			runtime->dma_bytes = size;
			return 0;
		}
		snd_es1968_free_memory(chip, chan->memory);
	}
	chan->memory = snd_es1968_new_memory(chip, size);
	if (chan->memory == NULL) {
		// snd_printd("cannot allocate dma buffer: size = %d\n", size);
		return -ENOMEM;
	}
	snd_pcm_set_runtime_buffer(substream, &chan->memory->buf);
	return 1; /* area was changed */
}

/* remove dma areas if allocated */
static int snd_es1968_hw_free(struct snd_pcm_substream *substream)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct esschan *chan;
	
	if (runtime->private_data == NULL)
		return 0;
	chan = runtime->private_data;
	if (chan->memory) {
		snd_es1968_free_memory(chip, chan->memory);
		chan->memory = NULL;
	}
	return 0;
}


/*
 * allocate APU pair
 */
static int snd_es1968_alloc_apu_pair(struct es1968 *chip, int type)
{
	int apu;

	for (apu = 0; apu < NR_APUS; apu += 2) {
		if (chip->apu[apu] == ESM_APU_FREE &&
		    chip->apu[apu + 1] == ESM_APU_FREE) {
			chip->apu[apu] = chip->apu[apu + 1] = type;
			return apu;
		}
	}
	return -EBUSY;
}

/*
 * release APU pair
 */
static void snd_es1968_free_apu_pair(struct es1968 *chip, int apu)
{
	chip->apu[apu] = chip->apu[apu + 1] = ESM_APU_FREE;
}


/******************
 * PCM open/close *
 ******************/

static int snd_es1968_playback_open(struct snd_pcm_substream *substream)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct esschan *es;
	int apu1;

	/* search 2 APUs */
	apu1 = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_PLAY);
	if (apu1 < 0)
		return apu1;

	es = kzalloc(sizeof(*es), GFP_KERNEL);
	if (!es) {
		snd_es1968_free_apu_pair(chip, apu1);
		return -ENOMEM;
	}

	es->apu[0] = apu1;
	es->apu[1] = apu1 + 1;
	es->apu_mode[0] = 0;
	es->apu_mode[1] = 0;
	es->running = 0;
	es->substream = substream;
	es->mode = ESM_MODE_PLAY;

	runtime->private_data = es;
	runtime->hw = snd_es1968_playback;
	runtime->hw.buffer_bytes_max = runtime->hw.period_bytes_max =
		calc_available_memory_size(chip);

	spin_lock_irq(&chip->substream_lock);
	list_add(&es->list, &chip->substream_list);
	spin_unlock_irq(&chip->substream_lock);

	return 0;
}

static int snd_es1968_capture_open(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct esschan *es;
	int apu1, apu2;

	apu1 = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_CAPTURE);
	if (apu1 < 0)
		return apu1;
	apu2 = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_RATECONV);
	if (apu2 < 0) {
		snd_es1968_free_apu_pair(chip, apu1);
		return apu2;
	}
	
	es = kzalloc(sizeof(*es), GFP_KERNEL);
	if (!es) {
		snd_es1968_free_apu_pair(chip, apu1);
		snd_es1968_free_apu_pair(chip, apu2);
		return -ENOMEM;
	}

	es->apu[0] = apu1;
	es->apu[1] = apu1 + 1;
	es->apu[2] = apu2;
	es->apu[3] = apu2 + 1;
	es->apu_mode[0] = 0;
	es->apu_mode[1] = 0;
	es->apu_mode[2] = 0;
	es->apu_mode[3] = 0;
	es->running = 0;
	es->substream = substream;
	es->mode = ESM_MODE_CAPTURE;

	/* get mixbuffer */
	if ((es->mixbuf = snd_es1968_new_memory(chip, ESM_MIXBUF_SIZE)) == NULL) {
		snd_es1968_free_apu_pair(chip, apu1);
		snd_es1968_free_apu_pair(chip, apu2);
		kfree(es);
                return -ENOMEM;
        }
	memset(es->mixbuf->buf.area, 0, ESM_MIXBUF_SIZE);

	runtime->private_data = es;
	runtime->hw = snd_es1968_capture;
	runtime->hw.buffer_bytes_max = runtime->hw.period_bytes_max =
		calc_available_memory_size(chip) - 1024; /* keep MIXBUF size */
	snd_pcm_hw_constraint_pow2(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES);

	spin_lock_irq(&chip->substream_lock);
	list_add(&es->list, &chip->substream_list);
	spin_unlock_irq(&chip->substream_lock);

	return 0;
}

static int snd_es1968_playback_close(struct snd_pcm_substream *substream)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct esschan *es;

	if (substream->runtime->private_data == NULL)
		return 0;
	es = substream->runtime->private_data;
	spin_lock_irq(&chip->substream_lock);
	list_del(&es->list);
	spin_unlock_irq(&chip->substream_lock);
	snd_es1968_free_apu_pair(chip, es->apu[0]);
	kfree(es);

	return 0;
}

static int snd_es1968_capture_close(struct snd_pcm_substream *substream)
{
	struct es1968 *chip = snd_pcm_substream_chip(substream);
	struct esschan *es;

	if (substream->runtime->private_data == NULL)
		return 0;
	es = substream->runtime->private_data;
	spin_lock_irq(&chip->substream_lock);
	list_del(&es->list);
	spin_unlock_irq(&chip->substream_lock);
	snd_es1968_free_memory(chip, es->mixbuf);
	snd_es1968_free_apu_pair(chip, es->apu[0]);
	snd_es1968_free_apu_pair(chip, es->apu[2]);
	kfree(es);

	return 0;
}

static struct snd_pcm_ops snd_es1968_playback_ops = {
	.open =		snd_es1968_playback_open,
	.close =	snd_es1968_playback_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	snd_es1968_hw_params,
	.hw_free =	snd_es1968_hw_free,
	.prepare =	snd_es1968_pcm_prepare,
	.trigger =	snd_es1968_pcm_trigger,
	.pointer =	snd_es1968_pcm_pointer,
};

static struct snd_pcm_ops snd_es1968_capture_ops = {
	.open =		snd_es1968_capture_open,
	.close =	snd_es1968_capture_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	snd_es1968_hw_params,
	.hw_free =	snd_es1968_hw_free,
	.prepare =	snd_es1968_pcm_prepare,
	.trigger =	snd_es1968_pcm_trigger,
	.pointer =	snd_es1968_pcm_pointer,
};


/*
 * measure clock
 */
#define CLOCK_MEASURE_BUFSIZE	16768	/* enough large for a single shot */

static void __devinit es1968_measure_clock(struct es1968 *chip)
{
	int i, apu;
	unsigned int pa, offset, t;
	struct esm_memory *memory;
	struct timeval start_time, stop_time;

	if (chip->clock == 0)
		chip->clock = 48000; /* default clock value */

	/* search 2 APUs (although one apu is enough) */
	if ((apu = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_PLAY)) < 0) {
		snd_printk(KERN_ERR "Hmm, cannot find empty APU pair!?\n");
		return;
	}
	if ((memory = snd_es1968_new_memory(chip, CLOCK_MEASURE_BUFSIZE)) == NULL) {
		snd_printk(KERN_ERR "cannot allocate dma buffer - using default clock %d\n", chip->clock);
		snd_es1968_free_apu_pair(chip, apu);
		return;
	}

	memset(memory->buf.area, 0, CLOCK_MEASURE_BUFSIZE);

	wave_set_register(chip, apu << 3, (memory->buf.addr - 0x10) & 0xfff8);

	pa = (unsigned int)((memory->buf.addr - chip->dma.addr) >> 1);
	pa |= 0x00400000;	/* System RAM (Bit 22) */

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

	apu_set_register(chip, apu, 0, 0x400f);
	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 + CLOCK_MEASURE_BUFSIZE/2) & 0xffff);
	apu_set_register(chip, apu, 7, CLOCK_MEASURE_BUFSIZE/2);
	apu_set_register(chip, apu, 8, 0x0000);
	apu_set_register(chip, apu, 9, 0xD000);
	apu_set_register(chip, apu, 10, 0x8F08);
	apu_set_register(chip, apu, 11, 0x0000);
	spin_lock_irq(&chip->reg_lock);
	outw(1, chip->io_port + 0x04); /* clear WP interrupts */
	outw(inw(chip->io_port + ESM_PORT_HOST_IRQ) | ESM_HIRQ_DSIE, chip->io_port + ESM_PORT_HOST_IRQ); /* enable WP ints */
	spin_unlock_irq(&chip->reg_lock);

	snd_es1968_apu_set_freq(chip, apu, ((unsigned int)48000 << 16) / chip->clock); /* 48000 Hz */

	chip->in_measurement = 1;
	chip->measure_apu = apu;
	spin_lock_irq(&chip->reg_lock);
	snd_es1968_bob_inc(chip, ESM_BOB_FREQ);
	__apu_set_register(chip, apu, 5, pa & 0xffff);
	snd_es1968_trigger_apu(chip, apu, ESM_APU_16BITLINEAR);
	do_gettimeofday(&start_time);
	spin_unlock_irq(&chip->reg_lock);
	msleep(50);
	spin_lock_irq(&chip->reg_lock);
	offset = __apu_get_register(chip, apu, 5);
	do_gettimeofday(&stop_time);
	snd_es1968_trigger_apu(chip, apu, 0); /* stop */
	snd_es1968_bob_dec(chip);
	chip->in_measurement = 0;
	spin_unlock_irq(&chip->reg_lock);

	/* check the current position */
	offset -= (pa & 0xffff);
	offset &= 0xfffe;
	offset += chip->measure_count * (CLOCK_MEASURE_BUFSIZE/2);

	t = stop_time.tv_sec - start_time.tv_sec;
	t *= 1000000;
	if (stop_time.tv_usec < start_time.tv_usec)
		t -= start_time.tv_usec - stop_time.tv_usec;
	else
		t += stop_time.tv_usec - start_time.tv_usec;
	if (t == 0) {
		snd_printk(KERN_ERR "?? calculation error..\n");
	} else {
		offset *= 1000;
		offset = (offset / t) * 1000 + ((offset % t) * 1000) / t;
		if (offset < 47500 || offset > 48500) {
			if (offset >= 40000 && offset <= 50000)
				chip->clock = (chip->clock * offset) / 48000;
		}
		printk(KERN_INFO "es1968: clocking to %d\n", chip->clock);
	}
	snd_es1968_free_memory(chip, memory);
	snd_es1968_free_apu_pair(chip, apu);
}


/*
 */

static void snd_es1968_pcm_free(struct snd_pcm *pcm)
{
	struct es1968 *esm = pcm->private_data;
	snd_es1968_free_dmabuf(esm);
	esm->pcm = NULL;
}

static int __devinit
snd_es1968_pcm(struct es1968 *chip, int device)
{
	struct snd_pcm *pcm;
	int err;

	/* get DMA buffer */
	if ((err = snd_es1968_init_dmabuf(chip)) < 0)
		return err;

	/* set PCMBAR */
	wave_set_register(chip, 0x01FC, chip->dma.addr >> 12);
	wave_set_register(chip, 0x01FD, chip->dma.addr >> 12);
	wave_set_register(chip, 0x01FE, chip->dma.addr >> 12);
	wave_set_register(chip, 0x01FF, chip->dma.addr >> 12);

	if ((err = snd_pcm_new(chip->card, "ESS Maestro", device,
			       chip->playback_streams,
			       chip->capture_streams, &pcm)) < 0)
		return err;

	pcm->private_data = chip;
	pcm->private_free = snd_es1968_pcm_free;

	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_es1968_playback_ops);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_es1968_capture_ops);

	pcm->info_flags = 0;

	strcpy(pcm->name, "ESS Maestro");

	chip->pcm = pcm;

	return 0;
}

/*
 * update pointer
 */
static void snd_es1968_update_pcm(struct es1968 *chip, struct esschan *es)
{
	unsigned int hwptr;
	unsigned int diff;
	struct snd_pcm_substream *subs = es->substream;
        
	if (subs == NULL || !es->running)
		return;

	hwptr = snd_es1968_get_dma_ptr(chip, es) << es->wav_shift;
	hwptr %= es->dma_size;

	diff = (es->dma_size + hwptr - es->hwptr) % es->dma_size;

	es->hwptr = hwptr;
	es->count += diff;

	if (es->count > es->frag_size) {
		spin_unlock(&chip->substream_lock);
		snd_pcm_period_elapsed(subs);
		spin_lock(&chip->substream_lock);
		es->count %= es->frag_size;
	}
}

/*