usbmixer.c

linux 内核源代码

	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
	if (! kctl) {
		snd_printk(KERN_ERR "cannot malloc kcontrol\n");
		kfree(namelist);
		kfree(cval);
		return -ENOMEM;
	}
	kctl->private_value = (unsigned long)namelist;
	kctl->private_free = usb_mixer_selector_elem_free;

	nameid = desc[desc[0] - 1];
	len = check_mapped_name(state, unitid, 0, kctl->id.name, sizeof(kctl->id.name));
	if (len)
		;
	else if (nameid)
		snd_usb_copy_string_desc(state, nameid, kctl->id.name, sizeof(kctl->id.name));
	else {
		len = get_term_name(state, &state->oterm,
				    kctl->id.name, sizeof(kctl->id.name), 0);
		if (! len)
			strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));

		if ((state->oterm.type & 0xff00) == 0x0100)
			strlcat(kctl->id.name, " Capture Source", sizeof(kctl->id.name));
		else
			strlcat(kctl->id.name, " Playback Source", sizeof(kctl->id.name));
	}

	snd_printdd(KERN_INFO "[%d] SU [%s] items = %d\n",
		    cval->id, kctl->id.name, num_ins);
	if ((err = add_control_to_empty(state, kctl)) < 0)
		return err;

	return 0;
}


/*
 * parse an audio unit recursively
 */

static int parse_audio_unit(struct mixer_build *state, int unitid)
{
	unsigned char *p1;

	if (test_and_set_bit(unitid, state->unitbitmap))
		return 0; /* the unit already visited */

	p1 = find_audio_control_unit(state, unitid);
	if (!p1) {
		snd_printk(KERN_ERR "usbaudio: unit %d not found!\n", unitid);
		return -EINVAL;
	}

	switch (p1[2]) {
	case INPUT_TERMINAL:
		return 0; /* NOP */
	case MIXER_UNIT:
		return parse_audio_mixer_unit(state, unitid, p1);
	case SELECTOR_UNIT:
		return parse_audio_selector_unit(state, unitid, p1);
	case FEATURE_UNIT:
		return parse_audio_feature_unit(state, unitid, p1);
	case PROCESSING_UNIT:
		return parse_audio_processing_unit(state, unitid, p1);
	case EXTENSION_UNIT:
		return parse_audio_extension_unit(state, unitid, p1);
	default:
		snd_printk(KERN_ERR "usbaudio: unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
		return -EINVAL;
	}
}

static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
{
	kfree(mixer->id_elems);
	if (mixer->urb) {
		kfree(mixer->urb->transfer_buffer);
		usb_free_urb(mixer->urb);
	}
	usb_free_urb(mixer->rc_urb);
	kfree(mixer->rc_setup_packet);
	kfree(mixer);
}

static int snd_usb_mixer_dev_free(struct snd_device *device)
{
	struct usb_mixer_interface *mixer = device->device_data;
	snd_usb_mixer_free(mixer);
	return 0;
}

/*
 * create mixer controls
 *
 * walk through all OUTPUT_TERMINAL descriptors to search for mixers
 */
static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
{
	unsigned char *desc;
	struct mixer_build state;
	int err;
	const struct usbmix_ctl_map *map;
	struct usb_host_interface *hostif;

	hostif = &usb_ifnum_to_if(mixer->chip->dev, mixer->ctrlif)->altsetting[0];
	memset(&state, 0, sizeof(state));
	state.chip = mixer->chip;
	state.mixer = mixer;
	state.buffer = hostif->extra;
	state.buflen = hostif->extralen;

	/* check the mapping table */
	for (map = usbmix_ctl_maps; map->id; map++) {
		if (map->id == state.chip->usb_id) {
			state.map = map->map;
			state.selector_map = map->selector_map;
			mixer->ignore_ctl_error = map->ignore_ctl_error;
			break;
		}
	}

	desc = NULL;
	while ((desc = snd_usb_find_csint_desc(hostif->extra, hostif->extralen, desc, OUTPUT_TERMINAL)) != NULL) {
		if (desc[0] < 9)
			continue; /* invalid descriptor? */
		set_bit(desc[3], state.unitbitmap);  /* mark terminal ID as visited */
		state.oterm.id = desc[3];
		state.oterm.type = combine_word(&desc[4]);
		state.oterm.name = desc[8];
		err = parse_audio_unit(&state, desc[7]);
		if (err < 0)
			return err;
	}
	return 0;
}

static void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer,
				    int unitid)
{
	struct usb_mixer_elem_info *info;

	for (info = mixer->id_elems[unitid]; info; info = info->next_id_elem)
		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
			       info->elem_id);
}

static void snd_usb_mixer_memory_change(struct usb_mixer_interface *mixer,
					int unitid)
{
	if (!mixer->rc_cfg)
		return;
	/* unit ids specific to Extigy/Audigy 2 NX: */
	switch (unitid) {
	case 0: /* remote control */
		mixer->rc_urb->dev = mixer->chip->dev;
		usb_submit_urb(mixer->rc_urb, GFP_ATOMIC);
		break;
	case 4: /* digital in jack */
	case 7: /* line in jacks */
	case 19: /* speaker out jacks */
	case 20: /* headphones out jack */
		break;
	default:
		snd_printd(KERN_DEBUG "memory change in unknown unit %d\n", unitid);
		break;
	}
}

static void snd_usb_mixer_status_complete(struct urb *urb)
{
	struct usb_mixer_interface *mixer = urb->context;

	if (urb->status == 0) {
		u8 *buf = urb->transfer_buffer;
		int i;

		for (i = urb->actual_length; i >= 2; buf += 2, i -= 2) {
			snd_printd(KERN_DEBUG "status interrupt: %02x %02x\n",
				   buf[0], buf[1]);
			/* ignore any notifications not from the control interface */
			if ((buf[0] & 0x0f) != 0)
				continue;
			if (!(buf[0] & 0x40))
				snd_usb_mixer_notify_id(mixer, buf[1]);
			else
				snd_usb_mixer_memory_change(mixer, buf[1]);
		}
	}
	if (urb->status != -ENOENT && urb->status != -ECONNRESET) {
		urb->dev = mixer->chip->dev;
		usb_submit_urb(urb, GFP_ATOMIC);
	}
}

/* create the handler for the optional status interrupt endpoint */
static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
{
	struct usb_host_interface *hostif;
	struct usb_endpoint_descriptor *ep;
	void *transfer_buffer;
	int buffer_length;
	unsigned int epnum;

	hostif = &usb_ifnum_to_if(mixer->chip->dev, mixer->ctrlif)->altsetting[0];
	/* we need one interrupt input endpoint */
	if (get_iface_desc(hostif)->bNumEndpoints < 1)
		return 0;
	ep = get_endpoint(hostif, 0);
	if ((ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) != USB_DIR_IN ||
	    (ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT)
		return 0;

	epnum = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
	if (!transfer_buffer)
		return -ENOMEM;
	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!mixer->urb) {
		kfree(transfer_buffer);
		return -ENOMEM;
	}
	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
			 usb_rcvintpipe(mixer->chip->dev, epnum),
			 transfer_buffer, buffer_length,
			 snd_usb_mixer_status_complete, mixer, ep->bInterval);
	usb_submit_urb(mixer->urb, GFP_KERNEL);
	return 0;
}

static void snd_usb_soundblaster_remote_complete(struct urb *urb)
{
	struct usb_mixer_interface *mixer = urb->context;
	const struct rc_config *rc = mixer->rc_cfg;
	u32 code;

	if (urb->status < 0 || urb->actual_length < rc->packet_length)
		return;

	code = mixer->rc_buffer[rc->offset];
	if (rc->length == 2)
		code |= mixer->rc_buffer[rc->offset + 1] << 8;

	/* the Mute button actually changes the mixer control */
	if (code == rc->mute_code)
		snd_usb_mixer_notify_id(mixer, rc->mute_mixer_id);
	mixer->rc_code = code;
	wmb();
	wake_up(&mixer->rc_waitq);
}

static int snd_usb_sbrc_hwdep_open(struct snd_hwdep *hw, struct file *file)
{
	struct usb_mixer_interface *mixer = hw->private_data;

	if (test_and_set_bit(0, &mixer->rc_hwdep_open))
		return -EBUSY;
	return 0;
}

static int snd_usb_sbrc_hwdep_release(struct snd_hwdep *hw, struct file *file)
{
	struct usb_mixer_interface *mixer = hw->private_data;

	clear_bit(0, &mixer->rc_hwdep_open);
	smp_mb__after_clear_bit();
	return 0;
}

static long snd_usb_sbrc_hwdep_read(struct snd_hwdep *hw, char __user *buf,
				     long count, loff_t *offset)
{
	struct usb_mixer_interface *mixer = hw->private_data;
	int err;
	u32 rc_code;

	if (count != 1 && count != 4)
		return -EINVAL;
	err = wait_event_interruptible(mixer->rc_waitq,
				       (rc_code = xchg(&mixer->rc_code, 0)) != 0);
	if (err == 0) {
		if (count == 1)
			err = put_user(rc_code, buf);
		else
			err = put_user(rc_code, (u32 __user *)buf);
	}
	return err < 0 ? err : count;
}

static unsigned int snd_usb_sbrc_hwdep_poll(struct snd_hwdep *hw, struct file *file,
					    poll_table *wait)
{
	struct usb_mixer_interface *mixer = hw->private_data;

	poll_wait(file, &mixer->rc_waitq, wait);
	return mixer->rc_code ? POLLIN | POLLRDNORM : 0;
}

static int snd_usb_soundblaster_remote_init(struct usb_mixer_interface *mixer)
{
	struct snd_hwdep *hwdep;
	int err, len, i;

	for (i = 0; i < ARRAY_SIZE(rc_configs); ++i)
		if (rc_configs[i].usb_id == mixer->chip->usb_id)
			break;
	if (i >= ARRAY_SIZE(rc_configs))
		return 0;
	mixer->rc_cfg = &rc_configs[i];

	len = mixer->rc_cfg->packet_length;
	
	init_waitqueue_head(&mixer->rc_waitq);
	err = snd_hwdep_new(mixer->chip->card, "SB remote control", 0, &hwdep);
	if (err < 0)
		return err;
	snprintf(hwdep->name, sizeof(hwdep->name),
		 "%s remote control", mixer->chip->card->shortname);
	hwdep->iface = SNDRV_HWDEP_IFACE_SB_RC;
	hwdep->private_data = mixer;
	hwdep->ops.read = snd_usb_sbrc_hwdep_read;
	hwdep->ops.open = snd_usb_sbrc_hwdep_open;
	hwdep->ops.release = snd_usb_sbrc_hwdep_release;
	hwdep->ops.poll = snd_usb_sbrc_hwdep_poll;

	mixer->rc_urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!mixer->rc_urb)
		return -ENOMEM;
	mixer->rc_setup_packet = kmalloc(sizeof(*mixer->rc_setup_packet), GFP_KERNEL);
	if (!mixer->rc_setup_packet) {
		usb_free_urb(mixer->rc_urb);
		mixer->rc_urb = NULL;
		return -ENOMEM;
	}
	mixer->rc_setup_packet->bRequestType =
		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
	mixer->rc_setup_packet->bRequest = GET_MEM;
	mixer->rc_setup_packet->wValue = cpu_to_le16(0);
	mixer->rc_setup_packet->wIndex = cpu_to_le16(0);
	mixer->rc_setup_packet->wLength = cpu_to_le16(len);
	usb_fill_control_urb(mixer->rc_urb, mixer->chip->dev,
			     usb_rcvctrlpipe(mixer->chip->dev, 0),
			     (u8*)mixer->rc_setup_packet, mixer->rc_buffer, len,
			     snd_usb_soundblaster_remote_complete, mixer);
	return 0;
}

#define snd_audigy2nx_led_info		snd_ctl_boolean_mono_info

static int snd_audigy2nx_led_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
	int index = kcontrol->private_value;

	ucontrol->value.integer.value[0] = mixer->audigy2nx_leds[index];
	return 0;
}

static int snd_audigy2nx_led_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
	int index = kcontrol->private_value;
	int value = ucontrol->value.integer.value[0];
	int err, changed;

	if (value > 1)
		return -EINVAL;
	changed = value != mixer->audigy2nx_leds[index];
	err = snd_usb_ctl_msg(mixer->chip->dev,
			      usb_sndctrlpipe(mixer->chip->dev, 0), 0x24,
			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
			      value, index + 2, NULL, 0, 100);
	if (err < 0)
		return err;
	mixer->audigy2nx_leds[index] = value;
	return changed;
}

static struct snd_kcontrol_new snd_audigy2nx_controls[] = {
	{
		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
		.name = "CMSS LED Switch",
		.info = snd_audigy2nx_led_info,
		.get = snd_audigy2nx_led_get,
		.put = snd_audigy2nx_led_put,
		.private_value = 0,
	},
	{
		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
		.name = "Power LED Switch",
		.info = snd_audigy2nx_led_info,
		.get = snd_audigy2nx_led_get,
		.put = snd_audigy2nx_led_put,
		.private_value = 1,
	},
	{
		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
		.name = "Dolby Digital LED Switch",
		.info = snd_audigy2nx_led_info,
		.get = snd_audigy2nx_led_get,
		.put = snd_audigy2nx_led_put,
		.private_value = 2,
	},
};

static int snd_audigy2nx_controls_create(struct usb_mixer_interface *mixer)
{
	int i, err;

	for (i = 0; i < ARRAY_SIZE(snd_audigy2nx_controls); ++i) {
		err = snd_ctl_add(mixer->chip->card,
				  snd_ctl_new1(&snd_audigy2nx_controls[i], mixer));
		if (err < 0)
			return err;
	}
	mixer->audigy2nx_leds[1] = 1; /* Power LED is on by default */
	return 0;
}

static void snd_audigy2nx_proc_read(struct snd_info_entry *entry,
				    struct snd_info_buffer *buffer)
{
	static const struct {
		int unitid;
		const char *name;
	} jacks[] = {
		{4,  "dig in "},
		{7,  "line in"},
		{19, "spk out"},
		{20, "hph out"},
	};
	struct usb_mixer_interface *mixer = entry->private_data;
	int i, err;
	u8 buf[3];

	snd_iprintf(buffer, "%s jacks\n\n", mixer->chip->card->shortname);
	for (i = 0; i < ARRAY_SIZE(jacks); ++i) {
		snd_iprintf(buffer, "%s: ", jacks[i].name);
		err = snd_usb_ctl_msg(mixer->chip->dev,
				      usb_rcvctrlpipe(mixer->chip->dev, 0),
				      GET_MEM, USB_DIR_IN | USB_TYPE_CLASS |
				      USB_RECIP_INTERFACE, 0,
				      jacks[i].unitid << 8, buf, 3, 100);
		if (err == 3 && buf[0] == 3)
			snd_iprintf(buffer, "%02x %02x\n", buf[1], buf[2]);
		else
			snd_iprintf(buffer, "?\n");
	}
}

int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif)
{
	static struct snd_device_ops dev_ops = {
		.dev_free = snd_usb_mixer_dev_free
	};
	struct usb_mixer_interface *mixer;
	int err;

	strcpy(chip->card->mixername, "USB Mixer");

	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
	if (!mixer)
		return -ENOMEM;
	mixer->chip = chip;
	mixer->ctrlif = ctrlif;
#ifdef IGNORE_CTL_ERROR
	mixer->ignore_ctl_error = 1;
#endif
	mixer->id_elems = kcalloc(256, sizeof(*mixer->id_elems), GFP_KERNEL);
	if (!mixer->id_elems) {
		kfree(mixer);
		return -ENOMEM;
	}

	if ((err = snd_usb_mixer_controls(mixer)) < 0 ||
	    (err = snd_usb_mixer_status_create(mixer)) < 0)
		goto _error;

	if ((err = snd_usb_soundblaster_remote_init(mixer)) < 0)
		goto _error;

	if (mixer->chip->usb_id == USB_ID(0x041e, 0x3020)) {
		struct snd_info_entry *entry;

		if ((err = snd_audigy2nx_controls_create(mixer)) < 0)
			goto _error;
		if (!snd_card_proc_new(chip->card, "audigy2nx", &entry))
			snd_info_set_text_ops(entry, mixer,
					      snd_audigy2nx_proc_read);
	}

	err = snd_device_new(chip->card, SNDRV_DEV_LOWLEVEL, mixer, &dev_ops);
	if (err < 0)
		goto _error;
	list_add(&mixer->list, &chip->mixer_list);
	return 0;

_error:
	snd_usb_mixer_free(mixer);
	return err;
}

void snd_usb_mixer_disconnect(struct list_head *p)
{
	struct usb_mixer_interface *mixer;
	
	mixer = list_entry(p, struct usb_mixer_interface, list);
	usb_kill_urb(mixer->urb);
	usb_kill_urb(mixer->rc_urb);
}