usbmidi.c

linux 内核源代码

		    (ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT)
			continue;
		ms_ep = (struct usb_ms_endpoint_descriptor*)hostep->extra;
		if (hostep->extralen < 4 ||
		    ms_ep->bLength < 4 ||
		    ms_ep->bDescriptorType != USB_DT_CS_ENDPOINT ||
		    ms_ep->bDescriptorSubtype != MS_GENERAL)
			continue;
		if ((ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT) {
			if (endpoints[epidx].out_ep) {
				if (++epidx >= MIDI_MAX_ENDPOINTS) {
					snd_printk(KERN_WARNING "too many endpoints\n");
					break;
				}
			}
			endpoints[epidx].out_ep = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
			if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)
				endpoints[epidx].out_interval = ep->bInterval;
			else if (snd_usb_get_speed(umidi->chip->dev) == USB_SPEED_LOW)
				/*
				 * Low speed bulk transfers don't exist, so
				 * force interrupt transfers for devices like
				 * ESI MIDI Mate that try to use them anyway.
				 */
				endpoints[epidx].out_interval = 1;
			endpoints[epidx].out_cables = (1 << ms_ep->bNumEmbMIDIJack) - 1;
			snd_printdd(KERN_INFO "EP %02X: %d jack(s)\n",
				    ep->bEndpointAddress, ms_ep->bNumEmbMIDIJack);
		} else {
			if (endpoints[epidx].in_ep) {
				if (++epidx >= MIDI_MAX_ENDPOINTS) {
					snd_printk(KERN_WARNING "too many endpoints\n");
					break;
				}
			}
			endpoints[epidx].in_ep = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
			if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)
				endpoints[epidx].in_interval = ep->bInterval;
			else if (snd_usb_get_speed(umidi->chip->dev) == USB_SPEED_LOW)
				endpoints[epidx].in_interval = 1;
			endpoints[epidx].in_cables = (1 << ms_ep->bNumEmbMIDIJack) - 1;
			snd_printdd(KERN_INFO "EP %02X: %d jack(s)\n",
				    ep->bEndpointAddress, ms_ep->bNumEmbMIDIJack);
		}
	}
	return 0;
}

/*
 * On Roland devices, use the second alternate setting to be able to use
 * the interrupt input endpoint.
 */
static void snd_usbmidi_switch_roland_altsetting(struct snd_usb_midi* umidi)
{
	struct usb_interface* intf;
	struct usb_host_interface *hostif;
	struct usb_interface_descriptor* intfd;

	intf = umidi->iface;
	if (!intf || intf->num_altsetting != 2)
		return;

	hostif = &intf->altsetting[1];
	intfd = get_iface_desc(hostif);
	if (intfd->bNumEndpoints != 2 ||
	    (get_endpoint(hostif, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_BULK ||
	    (get_endpoint(hostif, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT)
		return;

	snd_printdd(KERN_INFO "switching to altsetting %d with int ep\n",
		    intfd->bAlternateSetting);
	usb_set_interface(umidi->chip->dev, intfd->bInterfaceNumber,
			  intfd->bAlternateSetting);
}

/*
 * Try to find any usable endpoints in the interface.
 */
static int snd_usbmidi_detect_endpoints(struct snd_usb_midi* umidi,
					struct snd_usb_midi_endpoint_info* endpoint,
					int max_endpoints)
{
	struct usb_interface* intf;
	struct usb_host_interface *hostif;
	struct usb_interface_descriptor* intfd;
	struct usb_endpoint_descriptor* epd;
	int i, out_eps = 0, in_eps = 0;

	if (USB_ID_VENDOR(umidi->chip->usb_id) == 0x0582)
		snd_usbmidi_switch_roland_altsetting(umidi);

	if (endpoint[0].out_ep || endpoint[0].in_ep)
		return 0;	

	intf = umidi->iface;
	if (!intf || intf->num_altsetting < 1)
		return -ENOENT;
	hostif = intf->cur_altsetting;
	intfd = get_iface_desc(hostif);

	for (i = 0; i < intfd->bNumEndpoints; ++i) {
		epd = get_endpoint(hostif, i);
		if ((epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_BULK &&
		    (epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT)
			continue;
		if (out_eps < max_endpoints &&
		    (epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT) {
			endpoint[out_eps].out_ep = epd->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
			if ((epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)
				endpoint[out_eps].out_interval = epd->bInterval;
			++out_eps;
		}
		if (in_eps < max_endpoints &&
		    (epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN) {
			endpoint[in_eps].in_ep = epd->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
			if ((epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)
				endpoint[in_eps].in_interval = epd->bInterval;
			++in_eps;
		}
	}
	return (out_eps || in_eps) ? 0 : -ENOENT;
}

/*
 * Detects the endpoints for one-port-per-endpoint protocols.
 */
static int snd_usbmidi_detect_per_port_endpoints(struct snd_usb_midi* umidi,
						 struct snd_usb_midi_endpoint_info* endpoints)
{
	int err, i;
	
	err = snd_usbmidi_detect_endpoints(umidi, endpoints, MIDI_MAX_ENDPOINTS);
	for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i) {
		if (endpoints[i].out_ep)
			endpoints[i].out_cables = 0x0001;
		if (endpoints[i].in_ep)
			endpoints[i].in_cables = 0x0001;
	}
	return err;
}

/*
 * Detects the endpoints and ports of Yamaha devices.
 */
static int snd_usbmidi_detect_yamaha(struct snd_usb_midi* umidi,
				     struct snd_usb_midi_endpoint_info* endpoint)
{
	struct usb_interface* intf;
	struct usb_host_interface *hostif;
	struct usb_interface_descriptor* intfd;
	uint8_t* cs_desc;

	intf = umidi->iface;
	if (!intf)
		return -ENOENT;
	hostif = intf->altsetting;
	intfd = get_iface_desc(hostif);
	if (intfd->bNumEndpoints < 1)
		return -ENOENT;

	/*
	 * For each port there is one MIDI_IN/OUT_JACK descriptor, not
	 * necessarily with any useful contents.  So simply count 'em.
	 */
	for (cs_desc = hostif->extra;
	     cs_desc < hostif->extra + hostif->extralen && cs_desc[0] >= 2;
	     cs_desc += cs_desc[0]) {
		if (cs_desc[1] == USB_DT_CS_INTERFACE) {
			if (cs_desc[2] == MIDI_IN_JACK)
				endpoint->in_cables = (endpoint->in_cables << 1) | 1;
			else if (cs_desc[2] == MIDI_OUT_JACK)
				endpoint->out_cables = (endpoint->out_cables << 1) | 1;
		}
	}
	if (!endpoint->in_cables && !endpoint->out_cables)
		return -ENOENT;

	return snd_usbmidi_detect_endpoints(umidi, endpoint, 1);
}

/*
 * Creates the endpoints and their ports for Midiman devices.
 */
static int snd_usbmidi_create_endpoints_midiman(struct snd_usb_midi* umidi,
						struct snd_usb_midi_endpoint_info* endpoint)
{
	struct snd_usb_midi_endpoint_info ep_info;
	struct usb_interface* intf;
	struct usb_host_interface *hostif;
	struct usb_interface_descriptor* intfd;
	struct usb_endpoint_descriptor* epd;
	int cable, err;

	intf = umidi->iface;
	if (!intf)
		return -ENOENT;
	hostif = intf->altsetting;
	intfd = get_iface_desc(hostif);
	/*
	 * The various MidiSport devices have more or less random endpoint
	 * numbers, so we have to identify the endpoints by their index in
	 * the descriptor array, like the driver for that other OS does.
	 *
	 * There is one interrupt input endpoint for all input ports, one
	 * bulk output endpoint for even-numbered ports, and one for odd-
	 * numbered ports.  Both bulk output endpoints have corresponding
	 * input bulk endpoints (at indices 1 and 3) which aren't used.
	 */
	if (intfd->bNumEndpoints < (endpoint->out_cables > 0x0001 ? 5 : 3)) {
		snd_printdd(KERN_ERR "not enough endpoints\n");
		return -ENOENT;
	}

	epd = get_endpoint(hostif, 0);
	if ((epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK) != USB_DIR_IN ||
	    (epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT) {
		snd_printdd(KERN_ERR "endpoint[0] isn't interrupt\n");
		return -ENXIO;
	}
	epd = get_endpoint(hostif, 2);
	if ((epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK) != USB_DIR_OUT ||
	    (epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_BULK) {
		snd_printdd(KERN_ERR "endpoint[2] isn't bulk output\n");
		return -ENXIO;
	}
	if (endpoint->out_cables > 0x0001) {
		epd = get_endpoint(hostif, 4);
		if ((epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK) != USB_DIR_OUT ||
		    (epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_BULK) {
			snd_printdd(KERN_ERR "endpoint[4] isn't bulk output\n");
			return -ENXIO;
		}
	}

	ep_info.out_ep = get_endpoint(hostif, 2)->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
	ep_info.out_cables = endpoint->out_cables & 0x5555;
	err = snd_usbmidi_out_endpoint_create(umidi, &ep_info, &umidi->endpoints[0]);
	if (err < 0)
		return err;

	ep_info.in_ep = get_endpoint(hostif, 0)->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
	ep_info.in_interval = get_endpoint(hostif, 0)->bInterval;
	ep_info.in_cables = endpoint->in_cables;
	err = snd_usbmidi_in_endpoint_create(umidi, &ep_info, &umidi->endpoints[0]);
	if (err < 0)
		return err;

	if (endpoint->out_cables > 0x0001) {
		ep_info.out_ep = get_endpoint(hostif, 4)->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
		ep_info.out_cables = endpoint->out_cables & 0xaaaa;
		err = snd_usbmidi_out_endpoint_create(umidi, &ep_info, &umidi->endpoints[1]);
		if (err < 0)
			return err;
	}

	for (cable = 0; cable < 0x10; ++cable) {
		if (endpoint->out_cables & (1 << cable))
			snd_usbmidi_init_substream(umidi, SNDRV_RAWMIDI_STREAM_OUTPUT, cable,
						   &umidi->endpoints[cable & 1].out->ports[cable].substream);
		if (endpoint->in_cables & (1 << cable))
			snd_usbmidi_init_substream(umidi, SNDRV_RAWMIDI_STREAM_INPUT, cable,
						   &umidi->endpoints[0].in->ports[cable].substream);
	}
	return 0;
}

static struct snd_rawmidi_global_ops snd_usbmidi_ops = {
	.get_port_info = snd_usbmidi_get_port_info,
};

static int snd_usbmidi_create_rawmidi(struct snd_usb_midi* umidi,
				      int out_ports, int in_ports)
{
	struct snd_rawmidi *rmidi;
	int err;

	err = snd_rawmidi_new(umidi->chip->card, "USB MIDI",
			      umidi->chip->next_midi_device++,
			      out_ports, in_ports, &rmidi);
	if (err < 0)
		return err;
	strcpy(rmidi->name, umidi->chip->card->shortname);
	rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
			    SNDRV_RAWMIDI_INFO_INPUT |
			    SNDRV_RAWMIDI_INFO_DUPLEX;
	rmidi->ops = &snd_usbmidi_ops;
	rmidi->private_data = umidi;
	rmidi->private_free = snd_usbmidi_rawmidi_free;
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_usbmidi_output_ops);
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_usbmidi_input_ops);

	umidi->rmidi = rmidi;
	return 0;
}

/*
 * Temporarily stop input.
 */
void snd_usbmidi_input_stop(struct list_head* p)
{
	struct snd_usb_midi* umidi;
	int i;

	umidi = list_entry(p, struct snd_usb_midi, list);
	for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i) {
		struct snd_usb_midi_endpoint* ep = &umidi->endpoints[i];
		if (ep->in)
			usb_kill_urb(ep->in->urb);
	}
}

static void snd_usbmidi_input_start_ep(struct snd_usb_midi_in_endpoint* ep)
{
	if (ep) {
		struct urb* urb = ep->urb;
		urb->dev = ep->umidi->chip->dev;
		snd_usbmidi_submit_urb(urb, GFP_KERNEL);
	}
}

/*
 * Resume input after a call to snd_usbmidi_input_stop().
 */
void snd_usbmidi_input_start(struct list_head* p)
{
	struct snd_usb_midi* umidi;
	int i;

	umidi = list_entry(p, struct snd_usb_midi, list);
	for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i)
		snd_usbmidi_input_start_ep(umidi->endpoints[i].in);
}

/*
 * Creates and registers everything needed for a MIDI streaming interface.
 */
int snd_usb_create_midi_interface(struct snd_usb_audio* chip,
				  struct usb_interface* iface,
				  const struct snd_usb_audio_quirk* quirk)
{
	struct snd_usb_midi* umidi;
	struct snd_usb_midi_endpoint_info endpoints[MIDI_MAX_ENDPOINTS];
	int out_ports, in_ports;
	int i, err;

	umidi = kzalloc(sizeof(*umidi), GFP_KERNEL);
	if (!umidi)
		return -ENOMEM;
	umidi->chip = chip;
	umidi->iface = iface;
	umidi->quirk = quirk;
	umidi->usb_protocol_ops = &snd_usbmidi_standard_ops;
	init_timer(&umidi->error_timer);
	umidi->error_timer.function = snd_usbmidi_error_timer;
	umidi->error_timer.data = (unsigned long)umidi;

	/* detect the endpoint(s) to use */
	memset(endpoints, 0, sizeof(endpoints));
	switch (quirk ? quirk->type : QUIRK_MIDI_STANDARD_INTERFACE) {
	case QUIRK_MIDI_STANDARD_INTERFACE:
		err = snd_usbmidi_get_ms_info(umidi, endpoints);
		if (chip->usb_id == USB_ID(0x0763, 0x0150)) /* M-Audio Uno */
			umidi->usb_protocol_ops =
				&snd_usbmidi_maudio_broken_running_status_ops;
		break;
	case QUIRK_MIDI_FIXED_ENDPOINT:
		memcpy(&endpoints[0], quirk->data,
		       sizeof(struct snd_usb_midi_endpoint_info));
		err = snd_usbmidi_detect_endpoints(umidi, &endpoints[0], 1);
		break;
	case QUIRK_MIDI_YAMAHA:
		err = snd_usbmidi_detect_yamaha(umidi, &endpoints[0]);
		break;
	case QUIRK_MIDI_MIDIMAN:
		umidi->usb_protocol_ops = &snd_usbmidi_midiman_ops;
		memcpy(&endpoints[0], quirk->data,
		       sizeof(struct snd_usb_midi_endpoint_info));
		err = 0;
		break;
	case QUIRK_MIDI_NOVATION:
		umidi->usb_protocol_ops = &snd_usbmidi_novation_ops;
		err = snd_usbmidi_detect_per_port_endpoints(umidi, endpoints);
		break;
	case QUIRK_MIDI_RAW:
		umidi->usb_protocol_ops = &snd_usbmidi_raw_ops;
		err = snd_usbmidi_detect_per_port_endpoints(umidi, endpoints);
		break;
	case QUIRK_MIDI_EMAGIC:
		umidi->usb_protocol_ops = &snd_usbmidi_emagic_ops;
		memcpy(&endpoints[0], quirk->data,
		       sizeof(struct snd_usb_midi_endpoint_info));
		err = snd_usbmidi_detect_endpoints(umidi, &endpoints[0], 1);
		break;
	case QUIRK_MIDI_CME:
		umidi->usb_protocol_ops = &snd_usbmidi_cme_ops;
		err = snd_usbmidi_detect_per_port_endpoints(umidi, endpoints);
		break;
	default:
		snd_printd(KERN_ERR "invalid quirk type %d\n", quirk->type);
		err = -ENXIO;
		break;
	}
	if (err < 0) {
		kfree(umidi);
		return err;
	}

	/* create rawmidi device */
	out_ports = 0;
	in_ports = 0;
	for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i) {
		out_ports += snd_usbmidi_count_bits(endpoints[i].out_cables);
		in_ports += snd_usbmidi_count_bits(endpoints[i].in_cables);
	}
	err = snd_usbmidi_create_rawmidi(umidi, out_ports, in_ports);
	if (err < 0) {
		kfree(umidi);
		return err;
	}

	/* create endpoint/port structures */
	if (quirk && quirk->type == QUIRK_MIDI_MIDIMAN)
		err = snd_usbmidi_create_endpoints_midiman(umidi, &endpoints[0]);
	else
		err = snd_usbmidi_create_endpoints(umidi, endpoints);
	if (err < 0) {
		snd_usbmidi_free(umidi);
		return err;
	}

	list_add(&umidi->list, &umidi->chip->midi_list);

	for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i)
		snd_usbmidi_input_start_ep(umidi->endpoints[i].in);
	return 0;
}

EXPORT_SYMBOL(snd_usb_create_midi_interface);
EXPORT_SYMBOL(snd_usbmidi_input_stop);
EXPORT_SYMBOL(snd_usbmidi_input_start);
EXPORT_SYMBOL(snd_usbmidi_disconnect);