usbmixer.c

linux 内核源代码

	{ 0x0707, "Analog Tape" },
	{ 0x0708, "Phonograph" },
	{ 0x0709, "VCR Audio" },
	{ 0x070a, "Video Disk Audio" },
	{ 0x070b, "DVD Audio" },
	{ 0x070c, "TV Tuner Audio" },
	{ 0x070d, "Satellite Rec Audio" },
	{ 0x070e, "Cable Tuner Audio" },
	{ 0x070f, "DSS Audio" },
	{ 0x0710, "Radio Receiver" },
	{ 0x0711, "Radio Transmitter" },
	{ 0x0712, "Multi-Track Recorder" },
	{ 0x0713, "Synthesizer" },
	{ 0 },
};

static int get_term_name(struct mixer_build *state, struct usb_audio_term *iterm,
			 unsigned char *name, int maxlen, int term_only)
{
	struct iterm_name_combo *names;

	if (iterm->name)
		return snd_usb_copy_string_desc(state, iterm->name, name, maxlen);

	/* virtual type - not a real terminal */
	if (iterm->type >> 16) {
		if (term_only)
			return 0;
		switch (iterm->type >> 16) {
		case SELECTOR_UNIT:
			strcpy(name, "Selector"); return 8;
		case PROCESSING_UNIT:
			strcpy(name, "Process Unit"); return 12;
		case EXTENSION_UNIT:
			strcpy(name, "Ext Unit"); return 8;
		case MIXER_UNIT:
			strcpy(name, "Mixer"); return 5;
		default:
			return sprintf(name, "Unit %d", iterm->id);
		}
	}

	switch (iterm->type & 0xff00) {
	case 0x0100:
		strcpy(name, "PCM"); return 3;
	case 0x0200:
		strcpy(name, "Mic"); return 3;
	case 0x0400:
		strcpy(name, "Headset"); return 7;
	case 0x0500:
		strcpy(name, "Phone"); return 5;
	}

	for (names = iterm_names; names->type; names++)
		if (names->type == iterm->type) {
			strcpy(name, names->name);
			return strlen(names->name);
		}
	return 0;
}


/*
 * parse the source unit recursively until it reaches to a terminal
 * or a branched unit.
 */
static int check_input_term(struct mixer_build *state, int id, struct usb_audio_term *term)
{
	unsigned char *p1;

	memset(term, 0, sizeof(*term));
	while ((p1 = find_audio_control_unit(state, id)) != NULL) {
		term->id = id;
		switch (p1[2]) {
		case INPUT_TERMINAL:
			term->type = combine_word(p1 + 4);
			term->channels = p1[7];
			term->chconfig = combine_word(p1 + 8);
			term->name = p1[11];
			return 0;
		case FEATURE_UNIT:
			id = p1[4];
			break; /* continue to parse */
		case MIXER_UNIT:
			term->type = p1[2] << 16; /* virtual type */
			term->channels = p1[5 + p1[4]];
			term->chconfig = combine_word(p1 + 6 + p1[4]);
			term->name = p1[p1[0] - 1];
			return 0;
		case SELECTOR_UNIT:
			/* call recursively to retrieve the channel info */
			if (check_input_term(state, p1[5], term) < 0)
				return -ENODEV;
			term->type = p1[2] << 16; /* virtual type */
			term->id = id;
			term->name = p1[9 + p1[0] - 1];
			return 0;
		case PROCESSING_UNIT:
		case EXTENSION_UNIT:
			if (p1[6] == 1) {
				id = p1[7];
				break; /* continue to parse */
			}
			term->type = p1[2] << 16; /* virtual type */
			term->channels = p1[7 + p1[6]];
			term->chconfig = combine_word(p1 + 8 + p1[6]);
			term->name = p1[12 + p1[6] + p1[11 + p1[6]]];
			return 0;
		default:
			return -ENODEV;
		}
	}
	return -ENODEV;
}


/*
 * Feature Unit
 */

/* feature unit control information */
struct usb_feature_control_info {
	const char *name;
	unsigned int type;	/* control type (mute, volume, etc.) */
};

static struct usb_feature_control_info audio_feature_info[] = {
	{ "Mute",		USB_MIXER_INV_BOOLEAN },
	{ "Volume",		USB_MIXER_S16 },
	{ "Tone Control - Bass",	USB_MIXER_S8 },
	{ "Tone Control - Mid",		USB_MIXER_S8 },
	{ "Tone Control - Treble",	USB_MIXER_S8 },
	{ "Graphic Equalizer",		USB_MIXER_S8 }, /* FIXME: not implemeted yet */
	{ "Auto Gain Control",	USB_MIXER_BOOLEAN },
	{ "Delay Control",	USB_MIXER_U16 },
	{ "Bass Boost",		USB_MIXER_BOOLEAN },
	{ "Loudness",		USB_MIXER_BOOLEAN },
};


/* private_free callback */
static void usb_mixer_elem_free(struct snd_kcontrol *kctl)
{
	kfree(kctl->private_data);
	kctl->private_data = NULL;
}


/*
 * interface to ALSA control for feature/mixer units
 */

/*
 * retrieve the minimum and maximum values for the specified control
 */
static int get_min_max(struct usb_mixer_elem_info *cval, int default_min)
{
	/* for failsafe */
	cval->min = default_min;
	cval->max = cval->min + 1;
	cval->res = 1;

	if (cval->val_type == USB_MIXER_BOOLEAN ||
	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
		cval->initialized = 1;
	} else {
		int minchn = 0;
		if (cval->cmask) {
			int i;
			for (i = 0; i < MAX_CHANNELS; i++)
				if (cval->cmask & (1 << i)) {
					minchn = i + 1;
					break;
				}
		}
		if (get_ctl_value(cval, GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
		    get_ctl_value(cval, GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
			snd_printd(KERN_ERR "%d:%d: cannot get min/max values for control %d (id %d)\n",
				   cval->id, cval->mixer->ctrlif, cval->control, cval->id);
			return -EINVAL;
		}
		if (get_ctl_value(cval, GET_RES, (cval->control << 8) | minchn, &cval->res) < 0) {
			cval->res = 1;
		} else {
			int last_valid_res = cval->res;

			while (cval->res > 1) {
				if (set_ctl_value(cval, SET_RES, (cval->control << 8) | minchn, cval->res / 2) < 0)
					break;
				cval->res /= 2;
			}
			if (get_ctl_value(cval, GET_RES, (cval->control << 8) | minchn, &cval->res) < 0)
				cval->res = last_valid_res;
		}
		if (cval->res == 0)
			cval->res = 1;

		/* Additional checks for the proper resolution
		 *
		 * Some devices report smaller resolutions than actually
		 * reacting.  They don't return errors but simply clip
		 * to the lower aligned value.
		 */
		if (cval->min + cval->res < cval->max) {
			int last_valid_res = cval->res;
			int saved, test, check;
			get_cur_mix_value(cval, minchn, &saved);
			for (;;) {
				test = saved;
				if (test < cval->max)
					test += cval->res;
				else
					test -= cval->res;
				if (test < cval->min || test > cval->max ||
				    set_cur_mix_value(cval, minchn, test) ||
				    get_cur_mix_value(cval, minchn, &check)) {
					cval->res = last_valid_res;
					break;
				}
				if (test == check)
					break;
				cval->res *= 2;
			}
			set_cur_mix_value(cval, minchn, saved);
		}

		cval->initialized = 1;
	}
	return 0;
}


/* get a feature/mixer unit info */
static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;

	if (cval->val_type == USB_MIXER_BOOLEAN ||
	    cval->val_type == USB_MIXER_INV_BOOLEAN)
		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
	else
		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	uinfo->count = cval->channels;
	if (cval->val_type == USB_MIXER_BOOLEAN ||
	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
		uinfo->value.integer.min = 0;
		uinfo->value.integer.max = 1;
	} else {
		if (! cval->initialized)
			get_min_max(cval,  0);
		uinfo->value.integer.min = 0;
		uinfo->value.integer.max =
			(cval->max - cval->min + cval->res - 1) / cval->res;
	}
	return 0;
}

/* get the current value from feature/mixer unit */
static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int c, cnt, val, err;

	if (cval->cmask) {
		cnt = 0;
		for (c = 0; c < MAX_CHANNELS; c++) {
			if (cval->cmask & (1 << c)) {
				err = get_cur_mix_value(cval, c + 1, &val);
				if (err < 0) {
					if (cval->mixer->ignore_ctl_error) {
						ucontrol->value.integer.value[0] = cval->min;
						return 0;
					}
					snd_printd(KERN_ERR "cannot get current value for control %d ch %d: err = %d\n", cval->control, c + 1, err);
					return err;
				}
				val = get_relative_value(cval, val);
				ucontrol->value.integer.value[cnt] = val;
				cnt++;
			}
		}
	} else {
		/* master channel */
		err = get_cur_mix_value(cval, 0, &val);
		if (err < 0) {
			if (cval->mixer->ignore_ctl_error) {
				ucontrol->value.integer.value[0] = cval->min;
				return 0;
			}
			snd_printd(KERN_ERR "cannot get current value for control %d master ch: err = %d\n", cval->control, err);
			return err;
		}
		val = get_relative_value(cval, val);
		ucontrol->value.integer.value[0] = val;
	}
	return 0;
}

/* put the current value to feature/mixer unit */
static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int c, cnt, val, oval, err;
	int changed = 0;

	if (cval->cmask) {
		cnt = 0;
		for (c = 0; c < MAX_CHANNELS; c++) {
			if (cval->cmask & (1 << c)) {
				err = get_cur_mix_value(cval, c + 1, &oval);
				if (err < 0) {
					if (cval->mixer->ignore_ctl_error)
						return 0;
					return err;
				}
				val = ucontrol->value.integer.value[cnt];
				val = get_abs_value(cval, val);
				if (oval != val) {
					set_cur_mix_value(cval, c + 1, val);
					changed = 1;
				}
				get_cur_mix_value(cval, c + 1, &val);
				cnt++;
			}
		}
	} else {
		/* master channel */
		err = get_cur_mix_value(cval, 0, &oval);
		if (err < 0 && cval->mixer->ignore_ctl_error)
			return 0;
		if (err < 0)
			return err;
		val = ucontrol->value.integer.value[0];
		val = get_abs_value(cval, val);
		if (val != oval) {
			set_cur_mix_value(cval, 0, val);
			changed = 1;
		}
	}
	return changed;
}

static struct snd_kcontrol_new usb_feature_unit_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later manually */
	.info = mixer_ctl_feature_info,
	.get = mixer_ctl_feature_get,
	.put = mixer_ctl_feature_put,
};


/*
 * build a feature control
 */

static void build_feature_ctl(struct mixer_build *state, unsigned char *desc,
			      unsigned int ctl_mask, int control,
			      struct usb_audio_term *iterm, int unitid)
{
	unsigned int len = 0;
	int mapped_name = 0;
	int nameid = desc[desc[0] - 1];
	struct snd_kcontrol *kctl;
	struct usb_mixer_elem_info *cval;

	control++; /* change from zero-based to 1-based value */

	if (control == USB_FEATURE_GEQ) {
		/* FIXME: not supported yet */
		return;
	}

	if (check_ignored_ctl(state, unitid, control))
		return;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (! cval) {
		snd_printk(KERN_ERR "cannot malloc kcontrol\n");
		return;
	}
	cval->mixer = state->mixer;
	cval->id = unitid;
	cval->control = control;
	cval->cmask = ctl_mask;
	cval->val_type = audio_feature_info[control-1].type;
	if (ctl_mask == 0)
		cval->channels = 1;	/* master channel */
	else {
		int i, c = 0;
		for (i = 0; i < 16; i++)
			if (ctl_mask & (1 << i))
				c++;
		cval->channels = c;
	}

	/* get min/max values */
	get_min_max(cval, 0);

	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
	if (! kctl) {
		snd_printk(KERN_ERR "cannot malloc kcontrol\n");
		kfree(cval);
		return;
	}
	kctl->private_free = usb_mixer_elem_free;

	len = check_mapped_name(state, unitid, control, kctl->id.name, sizeof(kctl->id.name));
	mapped_name = len != 0;
	if (! len && nameid)
		len = snd_usb_copy_string_desc(state, nameid, kctl->id.name, sizeof(kctl->id.name));

	switch (control) {
	case USB_FEATURE_MUTE:
	case USB_FEATURE_VOLUME:
		/* determine the control name.  the rule is:
		 * - if a name id is given in descriptor, use it.
		 * - if the connected input can be determined, then use the name
		 *   of terminal type.
		 * - if the connected output can be determined, use it.
		 * - otherwise, anonymous name.
		 */
		if (! len) {
			len = get_term_name(state, iterm, kctl->id.name, sizeof(kctl->id.name), 1);
			if (! len)
				len = get_term_name(state, &state->oterm, kctl->id.name, sizeof(kctl->id.name), 1);
			if (! len)
				len = snprintf(kctl->id.name, sizeof(kctl->id.name),
					       "Feature %d", unitid);
		}
		/* determine the stream direction:
		 * if the connected output is USB stream, then it's likely a
		 * capture stream.  otherwise it should be playback (hopefully :)
		 */
		if (! mapped_name && ! (state->oterm.type >> 16)) {
			if ((state->oterm.type & 0xff00) == 0x0100) {
				len = strlcat(kctl->id.name, " Capture", sizeof(kctl->id.name));
			} else {
				len = strlcat(kctl->id.name + len, " Playback", sizeof(kctl->id.name));
			}
		}
		strlcat(kctl->id.name + len, control == USB_FEATURE_MUTE ? " Switch" : " Volume",
			sizeof(kctl->id.name));
		if (control == USB_FEATURE_VOLUME) {
			kctl->tlv.c = mixer_vol_tlv;
			kctl->vd[0].access |= 
				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
		}
		break;

	default:
		if (! len)
			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
				sizeof(kctl->id.name));
		break;
	}

	/* quirk for UDA1321/N101 */
	/* note that detection between firmware 2.1.1.7 (N101) and later 2.1.1.21 */
	/* is not very clear from datasheets */
	/* I hope that the min value is -15360 for newer firmware --jk */
	switch (state->chip->usb_id) {
	case USB_ID(0x0471, 0x0101):
	case USB_ID(0x0471, 0x0104):
	case USB_ID(0x0471, 0x0105):
	case USB_ID(0x0672, 0x1041):
		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
		    cval->min == -15616) {
			snd_printk(KERN_INFO "using volume control quirk for the UDA1321/N101 chip\n");
			cval->max = -256;
		}
	}

	snd_printdd(KERN_INFO "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
		    cval->id, kctl->id.name, cval->channels, cval->min, cval->max, cval->res);
	add_control_to_empty(state, kctl);
}



/*
 * parse a feature unit
 *
 * most of controlls are defined here.
 */
static int parse_audio_feature_unit(struct mixer_build *state, int unitid, unsigned char *ftr)
{
	int channels, i, j;
	struct usb_audio_term iterm;
	unsigned int master_bits, first_ch_bits;
	int err, csize;

	if (ftr[0] < 7 || ! (csize = ftr[5]) || ftr[0] < 7 + csize) {
		snd_printk(KERN_ERR "usbaudio: unit %u: invalid FEATURE_UNIT descriptor\n", unitid);
		return -EINVAL;
	}

	/* parse the source unit */
	if ((err = parse_audio_unit(state, ftr[4])) < 0)
		return err;

	/* determine the input source type and name */
	if (check_input_term(state, ftr[4], &iterm) < 0)
		return -EINVAL;

	channels = (ftr[0] - 7) / csize - 1;

	master_bits = snd_usb_combine_bytes(ftr + 6, csize);
	if (channels > 0)
		first_ch_bits = snd_usb_combine_bytes(ftr + 6 + csize, csize);
	else
		first_ch_bits = 0;
	/* check all control types */
	for (i = 0; i < 10; i++) {