rawmidi.c

linux 内核源代码

static unsigned int snd_rawmidi_poll(struct file *file, poll_table * wait)
{
	struct snd_rawmidi_file *rfile;
	struct snd_rawmidi_runtime *runtime;
	unsigned int mask;

	rfile = file->private_data;
	if (rfile->input != NULL) {
		runtime = rfile->input->runtime;
		snd_rawmidi_input_trigger(rfile->input, 1);
		poll_wait(file, &runtime->sleep, wait);
	}
	if (rfile->output != NULL) {
		runtime = rfile->output->runtime;
		poll_wait(file, &runtime->sleep, wait);
	}
	mask = 0;
	if (rfile->input != NULL) {
		if (snd_rawmidi_ready(rfile->input))
			mask |= POLLIN | POLLRDNORM;
	}
	if (rfile->output != NULL) {
		if (snd_rawmidi_ready(rfile->output))
			mask |= POLLOUT | POLLWRNORM;
	}
	return mask;
}

/*
 */
#ifdef CONFIG_COMPAT
#include "rawmidi_compat.c"
#else
#define snd_rawmidi_ioctl_compat	NULL
#endif

/*

 */

static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
				       struct snd_info_buffer *buffer)
{
	struct snd_rawmidi *rmidi;
	struct snd_rawmidi_substream *substream;
	struct snd_rawmidi_runtime *runtime;

	rmidi = entry->private_data;
	snd_iprintf(buffer, "%s\n\n", rmidi->name);
	mutex_lock(&rmidi->open_mutex);
	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_OUTPUT) {
		list_for_each_entry(substream,
				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
				    list) {
			snd_iprintf(buffer,
				    "Output %d\n"
				    "  Tx bytes     : %lu\n",
				    substream->number,
				    (unsigned long) substream->bytes);
			if (substream->opened) {
				runtime = substream->runtime;
				snd_iprintf(buffer,
				    "  Mode         : %s\n"
				    "  Buffer size  : %lu\n"
				    "  Avail        : %lu\n",
				    runtime->oss ? "OSS compatible" : "native",
				    (unsigned long) runtime->buffer_size,
				    (unsigned long) runtime->avail);
			}
		}
	}
	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_INPUT) {
		list_for_each_entry(substream,
				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
				    list) {
			snd_iprintf(buffer,
				    "Input %d\n"
				    "  Rx bytes     : %lu\n",
				    substream->number,
				    (unsigned long) substream->bytes);
			if (substream->opened) {
				runtime = substream->runtime;
				snd_iprintf(buffer,
					    "  Buffer size  : %lu\n"
					    "  Avail        : %lu\n"
					    "  Overruns     : %lu\n",
					    (unsigned long) runtime->buffer_size,
					    (unsigned long) runtime->avail,
					    (unsigned long) runtime->xruns);
			}
		}
	}
	mutex_unlock(&rmidi->open_mutex);
}

/*
 *  Register functions
 */

static const struct file_operations snd_rawmidi_f_ops =
{
	.owner =	THIS_MODULE,
	.read =		snd_rawmidi_read,
	.write =	snd_rawmidi_write,
	.open =		snd_rawmidi_open,
	.release =	snd_rawmidi_release,
	.poll =		snd_rawmidi_poll,
	.unlocked_ioctl =	snd_rawmidi_ioctl,
	.compat_ioctl =	snd_rawmidi_ioctl_compat,
};

static int snd_rawmidi_alloc_substreams(struct snd_rawmidi *rmidi,
					struct snd_rawmidi_str *stream,
					int direction,
					int count)
{
	struct snd_rawmidi_substream *substream;
	int idx;

	for (idx = 0; idx < count; idx++) {
		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
		if (substream == NULL) {
			snd_printk(KERN_ERR "rawmidi: cannot allocate substream\n");
			return -ENOMEM;
		}
		substream->stream = direction;
		substream->number = idx;
		substream->rmidi = rmidi;
		substream->pstr = stream;
		list_add_tail(&substream->list, &stream->substreams);
		stream->substream_count++;
	}
	return 0;
}

/**
 * snd_rawmidi_new - create a rawmidi instance
 * @card: the card instance
 * @id: the id string
 * @device: the device index
 * @output_count: the number of output streams
 * @input_count: the number of input streams
 * @rrawmidi: the pointer to store the new rawmidi instance
 *
 * Creates a new rawmidi instance.
 * Use snd_rawmidi_set_ops() to set the operators to the new instance.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_rawmidi_new(struct snd_card *card, char *id, int device,
		    int output_count, int input_count,
		    struct snd_rawmidi ** rrawmidi)
{
	struct snd_rawmidi *rmidi;
	int err;
	static struct snd_device_ops ops = {
		.dev_free = snd_rawmidi_dev_free,
		.dev_register = snd_rawmidi_dev_register,
		.dev_disconnect = snd_rawmidi_dev_disconnect,
	};

	snd_assert(rrawmidi != NULL, return -EINVAL);
	*rrawmidi = NULL;
	snd_assert(card != NULL, return -ENXIO);
	rmidi = kzalloc(sizeof(*rmidi), GFP_KERNEL);
	if (rmidi == NULL) {
		snd_printk(KERN_ERR "rawmidi: cannot allocate\n");
		return -ENOMEM;
	}
	rmidi->card = card;
	rmidi->device = device;
	mutex_init(&rmidi->open_mutex);
	init_waitqueue_head(&rmidi->open_wait);
	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams);
	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams);

	if (id != NULL)
		strlcpy(rmidi->id, id, sizeof(rmidi->id));
	if ((err = snd_rawmidi_alloc_substreams(rmidi,
						&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT],
						SNDRV_RAWMIDI_STREAM_INPUT,
						input_count)) < 0) {
		snd_rawmidi_free(rmidi);
		return err;
	}
	if ((err = snd_rawmidi_alloc_substreams(rmidi,
						&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT],
						SNDRV_RAWMIDI_STREAM_OUTPUT,
						output_count)) < 0) {
		snd_rawmidi_free(rmidi);
		return err;
	}
	if ((err = snd_device_new(card, SNDRV_DEV_RAWMIDI, rmidi, &ops)) < 0) {
		snd_rawmidi_free(rmidi);
		return err;
	}
	*rrawmidi = rmidi;
	return 0;
}

static void snd_rawmidi_free_substreams(struct snd_rawmidi_str *stream)
{
	struct snd_rawmidi_substream *substream;

	while (!list_empty(&stream->substreams)) {
		substream = list_entry(stream->substreams.next, struct snd_rawmidi_substream, list);
		list_del(&substream->list);
		kfree(substream);
	}
}

static int snd_rawmidi_free(struct snd_rawmidi *rmidi)
{
	snd_assert(rmidi != NULL, return -ENXIO);	

	snd_info_free_entry(rmidi->proc_entry);
	rmidi->proc_entry = NULL;
	mutex_lock(&register_mutex);
	if (rmidi->ops && rmidi->ops->dev_unregister)
		rmidi->ops->dev_unregister(rmidi);
	mutex_unlock(&register_mutex);

	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
	if (rmidi->private_free)
		rmidi->private_free(rmidi);
	kfree(rmidi);
	return 0;
}

static int snd_rawmidi_dev_free(struct snd_device *device)
{
	struct snd_rawmidi *rmidi = device->device_data;
	return snd_rawmidi_free(rmidi);
}

#if defined(CONFIG_SND_SEQUENCER) || (defined(MODULE) && defined(CONFIG_SND_SEQUENCER_MODULE))
static void snd_rawmidi_dev_seq_free(struct snd_seq_device *device)
{
	struct snd_rawmidi *rmidi = device->private_data;
	rmidi->seq_dev = NULL;
}
#endif

static int snd_rawmidi_dev_register(struct snd_device *device)
{
	int err;
	struct snd_info_entry *entry;
	char name[16];
	struct snd_rawmidi *rmidi = device->device_data;

	if (rmidi->device >= SNDRV_RAWMIDI_DEVICES)
		return -ENOMEM;
	mutex_lock(&register_mutex);
	if (snd_rawmidi_search(rmidi->card, rmidi->device)) {
		mutex_unlock(&register_mutex);
		return -EBUSY;
	}
	list_add_tail(&rmidi->list, &snd_rawmidi_devices);
	sprintf(name, "midiC%iD%i", rmidi->card->number, rmidi->device);
	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_RAWMIDI,
				       rmidi->card, rmidi->device,
				       &snd_rawmidi_f_ops, rmidi, name)) < 0) {
		snd_printk(KERN_ERR "unable to register rawmidi device %i:%i\n", rmidi->card->number, rmidi->device);
		list_del(&rmidi->list);
		mutex_unlock(&register_mutex);
		return err;
	}
	if (rmidi->ops && rmidi->ops->dev_register &&
	    (err = rmidi->ops->dev_register(rmidi)) < 0) {
		snd_unregister_device(SNDRV_DEVICE_TYPE_RAWMIDI, rmidi->card, rmidi->device);
		list_del(&rmidi->list);
		mutex_unlock(&register_mutex);
		return err;
	}
#ifdef CONFIG_SND_OSSEMUL
	rmidi->ossreg = 0;
	if ((int)rmidi->device == midi_map[rmidi->card->number]) {
		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
					    rmidi->card, 0, &snd_rawmidi_f_ops,
					    rmidi, name) < 0) {
			snd_printk(KERN_ERR "unable to register OSS rawmidi device %i:%i\n", rmidi->card->number, 0);
		} else {
			rmidi->ossreg++;
#ifdef SNDRV_OSS_INFO_DEV_MIDI
			snd_oss_info_register(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number, rmidi->name);
#endif
		}
	}
	if ((int)rmidi->device == amidi_map[rmidi->card->number]) {
		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
					    rmidi->card, 1, &snd_rawmidi_f_ops,
					    rmidi, name) < 0) {
			snd_printk(KERN_ERR "unable to register OSS rawmidi device %i:%i\n", rmidi->card->number, 1);
		} else {
			rmidi->ossreg++;
		}
	}
#endif /* CONFIG_SND_OSSEMUL */
	mutex_unlock(&register_mutex);
	sprintf(name, "midi%d", rmidi->device);
	entry = snd_info_create_card_entry(rmidi->card, name, rmidi->card->proc_root);
	if (entry) {
		entry->private_data = rmidi;
		entry->c.text.read = snd_rawmidi_proc_info_read;
		if (snd_info_register(entry) < 0) {
			snd_info_free_entry(entry);
			entry = NULL;
		}
	}
	rmidi->proc_entry = entry;
#if defined(CONFIG_SND_SEQUENCER) || (defined(MODULE) && defined(CONFIG_SND_SEQUENCER_MODULE))
	if (!rmidi->ops || !rmidi->ops->dev_register) { /* own registration mechanism */
		if (snd_seq_device_new(rmidi->card, rmidi->device, SNDRV_SEQ_DEV_ID_MIDISYNTH, 0, &rmidi->seq_dev) >= 0) {
			rmidi->seq_dev->private_data = rmidi;
			rmidi->seq_dev->private_free = snd_rawmidi_dev_seq_free;
			sprintf(rmidi->seq_dev->name, "MIDI %d-%d", rmidi->card->number, rmidi->device);
			snd_device_register(rmidi->card, rmidi->seq_dev);
		}
	}
#endif
	return 0;
}

static int snd_rawmidi_dev_disconnect(struct snd_device *device)
{
	struct snd_rawmidi *rmidi = device->device_data;

	mutex_lock(&register_mutex);
	list_del_init(&rmidi->list);
#ifdef CONFIG_SND_OSSEMUL
	if (rmidi->ossreg) {
		if ((int)rmidi->device == midi_map[rmidi->card->number]) {
			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 0);
#ifdef SNDRV_OSS_INFO_DEV_MIDI
			snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number);
#endif
		}
		if ((int)rmidi->device == amidi_map[rmidi->card->number])
			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 1);
		rmidi->ossreg = 0;
	}
#endif /* CONFIG_SND_OSSEMUL */
	snd_unregister_device(SNDRV_DEVICE_TYPE_RAWMIDI, rmidi->card, rmidi->device);
	mutex_unlock(&register_mutex);
	return 0;
}

/**
 * snd_rawmidi_set_ops - set the rawmidi operators
 * @rmidi: the rawmidi instance
 * @stream: the stream direction, SNDRV_RAWMIDI_STREAM_XXX
 * @ops: the operator table
 *
 * Sets the rawmidi operators for the given stream direction.
 */
void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
			 struct snd_rawmidi_ops *ops)
{
	struct snd_rawmidi_substream *substream;
	
	list_for_each_entry(substream, &rmidi->streams[stream].substreams, list)
		substream->ops = ops;
}

/*
 *  ENTRY functions
 */

static int __init alsa_rawmidi_init(void)
{

	snd_ctl_register_ioctl(snd_rawmidi_control_ioctl);
	snd_ctl_register_ioctl_compat(snd_rawmidi_control_ioctl);
#ifdef CONFIG_SND_OSSEMUL
	{ int i;
	/* check device map table */
	for (i = 0; i < SNDRV_CARDS; i++) {
		if (midi_map[i] < 0 || midi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
			snd_printk(KERN_ERR "invalid midi_map[%d] = %d\n", i, midi_map[i]);
			midi_map[i] = 0;
		}
		if (amidi_map[i] < 0 || amidi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
			snd_printk(KERN_ERR "invalid amidi_map[%d] = %d\n", i, amidi_map[i]);
			amidi_map[i] = 1;
		}
	}
	}
#endif /* CONFIG_SND_OSSEMUL */
	return 0;
}

static void __exit alsa_rawmidi_exit(void)
{
	snd_ctl_unregister_ioctl(snd_rawmidi_control_ioctl);
	snd_ctl_unregister_ioctl_compat(snd_rawmidi_control_ioctl);
}

module_init(alsa_rawmidi_init)
module_exit(alsa_rawmidi_exit)

EXPORT_SYMBOL(snd_rawmidi_output_params);
EXPORT_SYMBOL(snd_rawmidi_input_params);
EXPORT_SYMBOL(snd_rawmidi_drop_output);
EXPORT_SYMBOL(snd_rawmidi_drain_output);
EXPORT_SYMBOL(snd_rawmidi_drain_input);
EXPORT_SYMBOL(snd_rawmidi_receive);
EXPORT_SYMBOL(snd_rawmidi_transmit_empty);
EXPORT_SYMBOL(snd_rawmidi_transmit_peek);
EXPORT_SYMBOL(snd_rawmidi_transmit_ack);
EXPORT_SYMBOL(snd_rawmidi_transmit);
EXPORT_SYMBOL(snd_rawmidi_new);
EXPORT_SYMBOL(snd_rawmidi_set_ops);
EXPORT_SYMBOL(snd_rawmidi_info_select);
EXPORT_SYMBOL(snd_rawmidi_kernel_open);
EXPORT_SYMBOL(snd_rawmidi_kernel_release);
EXPORT_SYMBOL(snd_rawmidi_kernel_read);
EXPORT_SYMBOL(snd_rawmidi_kernel_write);