C++ snd_BUG_ON函数代码示例

/* This function routes the sound from a virtual channel to a real output */
static int set_vmixer_gain(struct echoaudio *chip, u16 output, u16 pipe,
			   int gain)
{
	int index;

	if (snd_BUG_ON(pipe >= num_pipes_out(chip) ||
		       output >= num_busses_out(chip)))
		return -EINVAL;

	if (wait_handshake(chip))
		return -EIO;

	chip->vmixer_gain[output][pipe] = gain;
	index = output * num_pipes_out(chip) + pipe;
	chip->comm_page->vmixer[index] = gain;

	DE_ACT(("set_vmixer_gain: pipe %d, out %d = %d\n", pipe, output, gain));
	return 0;
}

static int ca_midi_input_close(struct snd_rawmidi_substream *substream)
{
	struct snd_ca_midi *midi = substream->rmidi->private_data;
	unsigned long flags;

	if (snd_BUG_ON(!midi->dev_id))
		return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	midi->interrupt_disable(midi,midi->rx_enable);
	midi->midi_mode &= ~CA_MIDI_MODE_INPUT;
	midi->substream_input = NULL;
	if (!(midi->midi_mode & CA_MIDI_MODE_OUTPUT)) {
		spin_unlock_irqrestore(&midi->open_lock, flags);
		ca_midi_cmd(midi, midi->reset, 0);
	} else {
		spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return 0;
}

static ssize_t snd_compr_write(struct file *f, const char __user *buf,
		size_t count, loff_t *offset)
{
	struct snd_compr_file *data = f->private_data;
	struct snd_compr_stream *stream;
	size_t avail;
	int retval;

	if (snd_BUG_ON(!data))
		return -EFAULT;

	stream = &data->stream;
	mutex_lock(&stream->device->lock);
	
	if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
			stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
		mutex_unlock(&stream->device->lock);
		return -EBADFD;
	}

	avail = snd_compr_get_avail(stream);
	pr_debug("avail returned %zu\n", avail);
	
	if (avail > count)
		avail = count;

	if (stream->ops->copy) {
		char __user* cbuf = (char __user*)buf;
		retval = stream->ops->copy(stream, cbuf, avail);
	} else {
		retval = snd_compr_write_data(stream, buf, avail);
	}
	if (retval > 0)
		stream->runtime->total_bytes_available += retval;

	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
		pr_debug("stream prepared, Houston we are good to go\n");
	}

	mutex_unlock(&stream->device->lock);
	return retval;
}

static ssize_t snd_compr_write(struct file *f, const char __user *buf,
		size_t count, loff_t *offset)
{
	struct snd_compr_file *data = f->private_data;
	struct snd_compr_stream *stream;
	size_t avail;
	int retval;

	if (snd_BUG_ON(!data))
		return -EFAULT;

	stream = &data->stream;
	mutex_lock(&stream->device->lock);
	/* write is allowed when stream is running or has been steup */
	if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
			stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
		mutex_unlock(&stream->device->lock);
		return -EBADFD;
	}

	avail = snd_compr_get_avail(stream);
	pr_debug("avail returned %ld\n", (unsigned long)avail);
	/* calculate how much we can write to buffer */
	if (avail > count)
		avail = count;

	if (stream->ops->copy)
		retval = stream->ops->copy(stream, buf, avail);
	else
		retval = snd_compr_write_data(stream, buf, avail);
	if (retval > 0)
		stream->runtime->total_bytes_available += retval;

	/* while initiating the stream, write should be called before START
	 * call, so in setup move state */
	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
		pr_debug("stream prepared, Houston we are good to go\n");
	}

	mutex_unlock(&stream->device->lock);
	return retval;
}

static int ca_midi_output_open(struct snd_rawmidi_substream *substream)
{
	struct snd_ca_midi *midi = substream->rmidi->private_data;
	unsigned long flags;

	if (snd_BUG_ON(!midi->dev_id))
		return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	midi->midi_mode |= CA_MIDI_MODE_OUTPUT;
	midi->substream_output = substream;
	if (!(midi->midi_mode & CA_MIDI_MODE_INPUT)) {
		spin_unlock_irqrestore(&midi->open_lock, flags);
		ca_midi_cmd(midi, midi->reset, 1);
		ca_midi_cmd(midi, midi->enter_uart, 1);
	} else {
		spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return 0;
}

int snd_seq_pool_done(struct snd_seq_pool *pool)
{
	unsigned long flags;
	struct snd_seq_event_cell *ptr;
	int max_count = 5 * HZ;

	if (snd_BUG_ON(!pool))
		return -EINVAL;

	
	spin_lock_irqsave(&pool->lock, flags);
	pool->closing = 1;
	spin_unlock_irqrestore(&pool->lock, flags);

	if (waitqueue_active(&pool->output_sleep))
		wake_up(&pool->output_sleep);

	while (atomic_read(&pool->counter) > 0) {
		if (max_count == 0) {
			snd_printk(KERN_WARNING "snd_seq_pool_done timeout: %d cells remain\n", atomic_read(&pool->counter));
			break;
		}
		schedule_timeout_uninterruptible(1);
		max_count--;
	}
	
	
	spin_lock_irqsave(&pool->lock, flags);
	ptr = pool->ptr;
	pool->ptr = NULL;
	pool->free = NULL;
	pool->total_elements = 0;
	spin_unlock_irqrestore(&pool->lock, flags);

	vfree(ptr);

	spin_lock_irqsave(&pool->lock, flags);
	pool->closing = 0;
	spin_unlock_irqrestore(&pool->lock, flags);

	return 0;
}

void
snd_seq_oss_synth_cleanup(struct seq_oss_devinfo *dp)
{
	int i;
	struct seq_oss_synth *rec;
	struct seq_oss_synthinfo *info;

	if (snd_BUG_ON(dp->max_synthdev >= SNDRV_SEQ_OSS_MAX_SYNTH_DEVS))
		return;
	for (i = 0; i < dp->max_synthdev; i++) {
		info = &dp->synths[i];
		if (! info->opened)
			continue;
		if (info->is_midi) {
			if (midi_synth_dev.opened > 0) {
				snd_seq_oss_midi_close(dp, info->midi_mapped);
				midi_synth_dev.opened--;
			}
		} else {
			rec = get_sdev(i);
			if (rec == NULL)
				continue;
			if (rec->opened > 0) {
#ifdef CONFIG_DEBUG_PRINTK
				debug_printk(("synth %d closed\n", i));
#else
				debug_;
#endif
				rec->oper.close(&info->arg);
				module_put(rec->oper.owner);
				rec->opened = 0;
			}
			snd_use_lock_free(&rec->use_lock);
		}
		kfree(info->sysex);
		info->sysex = NULL;
		kfree(info->ch);
		info->ch = NULL;
	}
	dp->synth_opened = 0;
	dp->max_synthdev = 0;
}

/*
 * prepare playback/capture channel
 */
static int snd_nm256_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;

	if (snd_BUG_ON(!s))
		return -ENXIO;
	s->dma_size = frames_to_bytes(runtime, substream->runtime->buffer_size);
	s->period_size = frames_to_bytes(runtime, substream->runtime->period_size);
	s->periods = substream->runtime->periods;
	s->cur_period = 0;

	spin_lock_irq(&chip->reg_lock);
	s->running = 0;
	snd_nm256_set_format(chip, s, substream);
	spin_unlock_irq(&chip->reg_lock);

	return 0;
}

static int snd_hwdep_dev_disconnect(struct snd_device *device)
{
	struct snd_hwdep *hwdep = device->device_data;

	if (snd_BUG_ON(!hwdep))
		return -ENXIO;
	mutex_lock(&register_mutex);
	if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
		mutex_unlock(&register_mutex);
		return -EINVAL;
	}
#ifdef CONFIG_SND_OSSEMUL
	if (hwdep->ossreg)
		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
#endif
	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
	list_del_init(&hwdep->list);
	mutex_unlock(&register_mutex);
	return 0;
}

/* Send a buffer full of MIDI data to the DSP
Returns how many actually written or < 0 on error */
static int write_midi(struct echoaudio *chip, u8 *data, int bytes)
{
	if (snd_BUG_ON(bytes <= 0 || bytes >= MIDI_OUT_BUFFER_SIZE))
		return -EINVAL;

	if (wait_handshake(chip))
		return -EIO;

	/* HF4 indicates that it is safe to write MIDI output data */
	if (! (get_dsp_register(chip, CHI32_STATUS_REG) & CHI32_STATUS_REG_HF4))
		return 0;

	chip->comm_page->midi_output[0] = bytes;
	memcpy(&chip->comm_page->midi_output[1], data, bytes);
	chip->comm_page->midi_out_free_count = 0;
	clear_handshake(chip);
	send_vector(chip, DSP_VC_MIDI_WRITE);
	DE_MID(("write_midi: %d\n", bytes));
	return bytes;
}

/**
 * snd_pcm_lib_malloc_pages - allocate the DMA buffer
 * @substream: the substream to allocate the DMA buffer to
 * @size: the requested buffer size in bytes
 *
 * Allocates the DMA buffer on the BUS type given earlier to
 * snd_pcm_lib_preallocate_xxx_pages().
 *
 * Return: 1 if the buffer is changed, 0 if not changed, or a negative
 * code on failure.
 */
int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
{
	struct snd_pcm_runtime *runtime;
	struct snd_dma_buffer *dmab = NULL;

	if (PCM_RUNTIME_CHECK(substream))
		return -EINVAL;
	if (snd_BUG_ON(substream->dma_buffer.dev.type ==
		       SNDRV_DMA_TYPE_UNKNOWN))
		return -EINVAL;
	runtime = substream->runtime;

	if (runtime->dma_buffer_p) {
		/* perphaps, we might free the large DMA memory region
		   to save some space here, but the actual solution
		   costs us less time */
		if (runtime->dma_buffer_p->bytes >= size) {
			runtime->dma_bytes = size;
			return 0;	/* ok, do not change */
		}
		snd_pcm_lib_free_pages(substream);
	}
	if (substream->dma_buffer.area != NULL &&
	    substream->dma_buffer.bytes >= size) {
		dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
	} else {
		dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
		if (! dmab)
			return -ENOMEM;
		dmab->dev = substream->dma_buffer.dev;
		if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
					substream->dma_buffer.dev.dev,
					size, dmab) < 0) {
			kfree(dmab);
			return -ENOMEM;
		}
	}
	snd_pcm_set_runtime_buffer(substream, dmab);
	runtime->dma_bytes = size;
	return 1;			/* area was changed */
}

snd_pcm_sframes_t ksnd_pcm_mmap_commit(ksnd_pcm_t *pcm,
									   snd_pcm_uframes_t offset,
									   snd_pcm_uframes_t frames)
{
	snd_pcm_substream_t *substream = pcm->substream;
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_pcm_uframes_t appl_ptr;
	snd_pcm_sframes_t res = frames;
	int err;
	if (snd_BUG_ON(!substream))
		return -EFAULT;
	/* for SPDIF we need to run though the just committed PCM samples and
	 * add formating (unless raw mode is enabled)
	 */
//      BUG_ON(substream->pcm->card->number == 2); /* TODO: magic number */
	snd_pcm_stream_lock_irq(substream);
	switch (_ksnd_pcm_state(substream))
	{
		case SNDRV_PCM_STATE_XRUN:
			res = -EPIPE;
			goto _end_unlock;
		case SNDRV_PCM_STATE_SUSPENDED:
			res = -ESTRPIPE;
			goto _end_unlock;
	}
	appl_ptr = runtime->control->appl_ptr;
	/* verify no-one is interleaving access to the playback */
	// TODO: what about capture?
	BUG_ON(substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
		   (appl_ptr % runtime->buffer_size) != offset);
	appl_ptr += frames;
	if (appl_ptr >= runtime->boundary)
		appl_ptr = 0;
	err = _ksnd_pcm_update_appl_ptr(substream, appl_ptr);
	if (err < 0)
		res = err;
_end_unlock:
	snd_pcm_stream_unlock_irq(substream);
	return res;
}

/* common trigger callback
 * calling the lowlevel callbacks in it
 */
static int snd_atiixp_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct atiixp *chip = snd_pcm_substream_chip(substream);
	struct atiixp_dma *dma = substream->runtime->private_data;
	int err = 0;

	if (snd_BUG_ON(!dma->ops->enable_transfer ||
		       !dma->ops->flush_dma))
		return -EINVAL;

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	case SNDRV_PCM_TRIGGER_RESUME:
		dma->ops->enable_transfer(chip, 1);
		dma->running = 1;
		dma->suspended = 0;
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		dma->ops->enable_transfer(chip, 0);
		dma->running = 0;
		dma->suspended = cmd == SNDRV_PCM_TRIGGER_SUSPEND;
		break;
	default:
		err = -EINVAL;
		break;
	}
	if (! err) {
		snd_atiixp_check_bus_busy(chip);
		if (cmd == SNDRV_PCM_TRIGGER_STOP) {
			dma->ops->flush_dma(chip);
			snd_atiixp_check_bus_busy(chip);
		}
	}
	spin_unlock(&chip->reg_lock);
	return err;
}

static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
	unsigned long flags;
	int err = 0;

	emu = midi->emu;
	if (snd_BUG_ON(!emu))
		return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	snd_emu10k1_intr_disable(emu, midi->tx_enable);
	midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
	midi->substream_output = NULL;
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
		spin_unlock_irqrestore(&midi->open_lock, flags);
		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
	} else {
		spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return err;
}

int snd_cs8427_iec958_pcm(struct snd_i2c_device *cs8427, unsigned int rate)
{
	struct cs8427 *chip;
	char *status;
	int err, reset;

	if (snd_BUG_ON(!cs8427))
		return -ENXIO;
	chip = cs8427->private_data;
	status = chip->playback.pcm_status;
	snd_i2c_lock(cs8427->bus);
	if (status[0] & IEC958_AES0_PROFESSIONAL) {
		status[0] &= ~IEC958_AES0_PRO_FS;
		switch (rate) {
		case 32000: status[0] |= IEC958_AES0_PRO_FS_32000; break;
		case 44100: status[0] |= IEC958_AES0_PRO_FS_44100; break;
		case 48000: status[0] |= IEC958_AES0_PRO_FS_48000; break;
		default: status[0] |= IEC958_AES0_PRO_FS_NOTID; break;
		}
	} else {
		status[3] &= ~IEC958_AES3_CON_FS;
		switch (rate) {
		case 32000: status[3] |= IEC958_AES3_CON_FS_32000; break;
		case 44100: status[3] |= IEC958_AES3_CON_FS_44100; break;
		case 48000: status[3] |= IEC958_AES3_CON_FS_48000; break;
		}
	}
	err = snd_cs8427_send_corudata(cs8427, 0, status, 24);
	if (err > 0)
		snd_ctl_notify(cs8427->bus->card,
			       SNDRV_CTL_EVENT_MASK_VALUE,
			       &chip->playback.pcm_ctl->id);
	reset = chip->rate != rate;
	chip->rate = rate;
	snd_i2c_unlock(cs8427->bus);
	if (reset)
		snd_cs8427_reset(cs8427);
	return err < 0 ? err : 0;
}