usbmixer.c

linux 内核源代码

		unsigned int ch_bits = 0;
		for (j = 0; j < channels; j++) {
			unsigned int mask = snd_usb_combine_bytes(ftr + 6 + csize * (j+1), csize);
			if (mask & (1 << i))
				ch_bits |= (1 << j);
		}
		if (ch_bits & 1) /* the first channel must be set (for ease of programming) */
			build_feature_ctl(state, ftr, ch_bits, i, &iterm, unitid);
		if (master_bits & (1 << i))
			build_feature_ctl(state, ftr, 0, i, &iterm, unitid);
	}

	return 0;
}


/*
 * Mixer Unit
 */

/*
 * build a mixer unit control
 *
 * the callbacks are identical with feature unit.
 * input channel number (zero based) is given in control field instead.
 */

static void build_mixer_unit_ctl(struct mixer_build *state, unsigned char *desc,
				 int in_pin, int in_ch, int unitid,
				 struct usb_audio_term *iterm)
{
	struct usb_mixer_elem_info *cval;
	unsigned int input_pins = desc[4];
	unsigned int num_outs = desc[5 + input_pins];
	unsigned int i, len;
	struct snd_kcontrol *kctl;

	if (check_ignored_ctl(state, unitid, 0))
		return;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (! cval)
		return;

	cval->mixer = state->mixer;
	cval->id = unitid;
	cval->control = in_ch + 1; /* based on 1 */
	cval->val_type = USB_MIXER_S16;
	for (i = 0; i < num_outs; i++) {
		if (check_matrix_bitmap(desc + 9 + input_pins, in_ch, i, num_outs)) {
			cval->cmask |= (1 << i);
			cval->channels++;
		}
	}

	/* 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, 0, kctl->id.name, sizeof(kctl->id.name));
	if (! len)
		len = get_term_name(state, iterm, kctl->id.name, sizeof(kctl->id.name), 0);
	if (! len)
		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
	strlcat(kctl->id.name + len, " Volume", sizeof(kctl->id.name));

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


/*
 * parse a mixer unit
 */
static int parse_audio_mixer_unit(struct mixer_build *state, int unitid, unsigned char *desc)
{
	struct usb_audio_term iterm;
	int input_pins, num_ins, num_outs;
	int pin, ich, err;

	if (desc[0] < 11 || ! (input_pins = desc[4]) || ! (num_outs = desc[5 + input_pins])) {
		snd_printk(KERN_ERR "invalid MIXER UNIT descriptor %d\n", unitid);
		return -EINVAL;
	}
	/* no bmControls field (e.g. Maya44) -> ignore */
	if (desc[0] <= 10 + input_pins) {
		snd_printdd(KERN_INFO "MU %d has no bmControls field\n", unitid);
		return 0;
	}

	num_ins = 0;
	ich = 0;
	for (pin = 0; pin < input_pins; pin++) {
		err = parse_audio_unit(state, desc[5 + pin]);
		if (err < 0)
			return err;
		err = check_input_term(state, desc[5 + pin], &iterm);
		if (err < 0)
			return err;
		num_ins += iterm.channels;
		for (; ich < num_ins; ++ich) {
			int och, ich_has_controls = 0;

			for (och = 0; och < num_outs; ++och) {
				if (check_matrix_bitmap(desc + 9 + input_pins,
							ich, och, num_outs)) {
					ich_has_controls = 1;
					break;
				}
			}
			if (ich_has_controls)
				build_mixer_unit_ctl(state, desc, pin, ich,
						     unitid, &iterm);
		}
	}
	return 0;
}


/*
 * Processing Unit / Extension Unit
 */

/* get callback for processing/extension unit */
static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int err, val;

	err = get_cur_ctl_value(cval, cval->control << 8, &val);
	if (err < 0 && cval->mixer->ignore_ctl_error) {
		ucontrol->value.integer.value[0] = cval->min;
		return 0;
	}
	if (err < 0)
		return err;
	val = get_relative_value(cval, val);
	ucontrol->value.integer.value[0] = val;
	return 0;
}

/* put callback for processing/extension unit */
static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, oval, err;

	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
	if (err < 0) {
		if (cval->mixer->ignore_ctl_error)
			return 0;
		return err;
	}
	val = ucontrol->value.integer.value[0];
	val = get_abs_value(cval, val);
	if (val != oval) {
		set_cur_ctl_value(cval, cval->control << 8, val);
		return 1;
	}
	return 0;
}

/* alsa control interface for processing/extension unit */
static struct snd_kcontrol_new mixer_procunit_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later */
	.info = mixer_ctl_feature_info,
	.get = mixer_ctl_procunit_get,
	.put = mixer_ctl_procunit_put,
};


/*
 * predefined data for processing units
 */
struct procunit_value_info {
	int control;
	char *suffix;
	int val_type;
	int min_value;
};

struct procunit_info {
	int type;
	char *name;
	struct procunit_value_info *values;
};

static struct procunit_value_info updown_proc_info[] = {
	{ USB_PROC_UPDOWN_SWITCH, "Switch", USB_MIXER_BOOLEAN },
	{ USB_PROC_UPDOWN_MODE_SEL, "Mode Select", USB_MIXER_U8, 1 },
	{ 0 }
};
static struct procunit_value_info prologic_proc_info[] = {
	{ USB_PROC_PROLOGIC_SWITCH, "Switch", USB_MIXER_BOOLEAN },
	{ USB_PROC_PROLOGIC_MODE_SEL, "Mode Select", USB_MIXER_U8, 1 },
	{ 0 }
};
static struct procunit_value_info threed_enh_proc_info[] = {
	{ USB_PROC_3DENH_SWITCH, "Switch", USB_MIXER_BOOLEAN },
	{ USB_PROC_3DENH_SPACE, "Spaciousness", USB_MIXER_U8 },
	{ 0 }
};
static struct procunit_value_info reverb_proc_info[] = {
	{ USB_PROC_REVERB_SWITCH, "Switch", USB_MIXER_BOOLEAN },
	{ USB_PROC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
	{ USB_PROC_REVERB_TIME, "Time", USB_MIXER_U16 },
	{ USB_PROC_REVERB_DELAY, "Delay", USB_MIXER_U8 },
	{ 0 }
};
static struct procunit_value_info chorus_proc_info[] = {
	{ USB_PROC_CHORUS_SWITCH, "Switch", USB_MIXER_BOOLEAN },
	{ USB_PROC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
	{ USB_PROC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
	{ USB_PROC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
	{ 0 }
};
static struct procunit_value_info dcr_proc_info[] = {
	{ USB_PROC_DCR_SWITCH, "Switch", USB_MIXER_BOOLEAN },
	{ USB_PROC_DCR_RATIO, "Ratio", USB_MIXER_U16 },
	{ USB_PROC_DCR_MAX_AMP, "Max Amp", USB_MIXER_S16 },
	{ USB_PROC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
	{ USB_PROC_DCR_ATTACK, "Attack Time", USB_MIXER_U16 },
	{ USB_PROC_DCR_RELEASE, "Release Time", USB_MIXER_U16 },
	{ 0 }
};

static struct procunit_info procunits[] = {
	{ USB_PROC_UPDOWN, "Up Down", updown_proc_info },
	{ USB_PROC_PROLOGIC, "Dolby Prologic", prologic_proc_info },
	{ USB_PROC_3DENH, "3D Stereo Extender", threed_enh_proc_info },
	{ USB_PROC_REVERB, "Reverb", reverb_proc_info },
	{ USB_PROC_CHORUS, "Chorus", chorus_proc_info },
	{ USB_PROC_DCR, "DCR", dcr_proc_info },
	{ 0 },
};

/*
 * build a processing/extension unit
 */
static int build_audio_procunit(struct mixer_build *state, int unitid, unsigned char *dsc, struct procunit_info *list, char *name)
{
	int num_ins = dsc[6];
	struct usb_mixer_elem_info *cval;
	struct snd_kcontrol *kctl;
	int i, err, nameid, type, len;
	struct procunit_info *info;
	struct procunit_value_info *valinfo;
	static struct procunit_value_info default_value_info[] = {
		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
		{ 0 }
	};
	static struct procunit_info default_info = {
		0, NULL, default_value_info
	};

	if (dsc[0] < 13 || dsc[0] < 13 + num_ins || dsc[0] < num_ins + dsc[11 + num_ins]) {
		snd_printk(KERN_ERR "invalid %s descriptor (id %d)\n", name, unitid);
		return -EINVAL;
	}

	for (i = 0; i < num_ins; i++) {
		if ((err = parse_audio_unit(state, dsc[7 + i])) < 0)
			return err;
	}

	type = combine_word(&dsc[4]);
	for (info = list; info && info->type; info++)
		if (info->type == type)
			break;
	if (! info || ! info->type)
		info = &default_info;

	for (valinfo = info->values; valinfo->control; valinfo++) {
		/* FIXME: bitmap might be longer than 8bit */
		if (! (dsc[12 + num_ins] & (1 << (valinfo->control - 1))))
			continue;
		if (check_ignored_ctl(state, unitid, valinfo->control))
			continue;
		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
		if (! cval) {
			snd_printk(KERN_ERR "cannot malloc kcontrol\n");
			return -ENOMEM;
		}
		cval->mixer = state->mixer;
		cval->id = unitid;
		cval->control = valinfo->control;
		cval->val_type = valinfo->val_type;
		cval->channels = 1;

		/* get min/max values */
		if (type == USB_PROC_UPDOWN && cval->control == USB_PROC_UPDOWN_MODE_SEL) {
			/* FIXME: hard-coded */
			cval->min = 1;
			cval->max = dsc[15];
			cval->res = 1;
			cval->initialized = 1;
		} else
			get_min_max(cval, valinfo->min_value);

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

		if (check_mapped_name(state, unitid, cval->control, kctl->id.name, sizeof(kctl->id.name)))
			;
		else if (info->name)
			strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
		else {
			nameid = dsc[12 + num_ins + dsc[11 + num_ins]];
			len = 0;
			if (nameid)
				len = snd_usb_copy_string_desc(state, nameid, kctl->id.name, sizeof(kctl->id.name));
			if (! len)
				strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
		}
		strlcat(kctl->id.name, " ", sizeof(kctl->id.name));
		strlcat(kctl->id.name, valinfo->suffix, sizeof(kctl->id.name));

		snd_printdd(KERN_INFO "[%d] PU [%s] ch = %d, val = %d/%d\n",
			    cval->id, kctl->id.name, cval->channels, cval->min, cval->max);
		if ((err = add_control_to_empty(state, kctl)) < 0)
			return err;
	}
	return 0;
}


static int parse_audio_processing_unit(struct mixer_build *state, int unitid, unsigned char *desc)
{
	return build_audio_procunit(state, unitid, desc, procunits, "Processing Unit");
}

static int parse_audio_extension_unit(struct mixer_build *state, int unitid, unsigned char *desc)
{
	return build_audio_procunit(state, unitid, desc, NULL, "Extension Unit");
}


/*
 * Selector Unit
 */

/* info callback for selector unit
 * use an enumerator type for routing
 */
static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	char **itemlist = (char **)kcontrol->private_value;

	snd_assert(itemlist, return -EINVAL);
	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
	uinfo->count = 1;
	uinfo->value.enumerated.items = cval->max;
	if ((int)uinfo->value.enumerated.item >= cval->max)
		uinfo->value.enumerated.item = cval->max - 1;
	strcpy(uinfo->value.enumerated.name, itemlist[uinfo->value.enumerated.item]);
	return 0;
}

/* get callback for selector unit */
static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, err;

	err = get_cur_ctl_value(cval, 0, &val);
	if (err < 0) {
		if (cval->mixer->ignore_ctl_error) {
			ucontrol->value.enumerated.item[0] = 0;
			return 0;
		}
		return err;
	}
	val = get_relative_value(cval, val);
	ucontrol->value.enumerated.item[0] = val;
	return 0;
}

/* put callback for selector unit */
static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, oval, err;

	err = get_cur_ctl_value(cval, 0, &oval);
	if (err < 0) {
		if (cval->mixer->ignore_ctl_error)
			return 0;
		return err;
	}
	val = ucontrol->value.enumerated.item[0];
	val = get_abs_value(cval, val);
	if (val != oval) {
		set_cur_ctl_value(cval, 0, val);
		return 1;
	}
	return 0;
}

/* alsa control interface for selector unit */
static struct snd_kcontrol_new mixer_selectunit_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later */
	.info = mixer_ctl_selector_info,
	.get = mixer_ctl_selector_get,
	.put = mixer_ctl_selector_put,
};


/* private free callback.
 * free both private_data and private_value
 */
static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
{
	int i, num_ins = 0;

	if (kctl->private_data) {
		struct usb_mixer_elem_info *cval = kctl->private_data;
		num_ins = cval->max;
		kfree(cval);
		kctl->private_data = NULL;
	}
	if (kctl->private_value) {
		char **itemlist = (char **)kctl->private_value;
		for (i = 0; i < num_ins; i++)
			kfree(itemlist[i]);
		kfree(itemlist);
		kctl->private_value = 0;
	}
}

/*
 * parse a selector unit
 */
static int parse_audio_selector_unit(struct mixer_build *state, int unitid, unsigned char *desc)
{
	unsigned int num_ins = desc[4];
	unsigned int i, nameid, len;
	int err;
	struct usb_mixer_elem_info *cval;
	struct snd_kcontrol *kctl;
	char **namelist;

	if (! num_ins || desc[0] < 5 + num_ins) {
		snd_printk(KERN_ERR "invalid SELECTOR UNIT descriptor %d\n", unitid);
		return -EINVAL;
	}

	for (i = 0; i < num_ins; i++) {
		if ((err = parse_audio_unit(state, desc[5 + i])) < 0)
			return err;
	}

	if (num_ins == 1) /* only one ? nonsense! */
		return 0;

	if (check_ignored_ctl(state, unitid, 0))
		return 0;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (! cval) {
		snd_printk(KERN_ERR "cannot malloc kcontrol\n");
		return -ENOMEM;
	}
	cval->mixer = state->mixer;
	cval->id = unitid;
	cval->val_type = USB_MIXER_U8;
	cval->channels = 1;
	cval->min = 1;
	cval->max = num_ins;
	cval->res = 1;
	cval->initialized = 1;

	namelist = kmalloc(sizeof(char *) * num_ins, GFP_KERNEL);
	if (! namelist) {
		snd_printk(KERN_ERR "cannot malloc\n");
		kfree(cval);
		return -ENOMEM;
	}
#define MAX_ITEM_NAME_LEN	64
	for (i = 0; i < num_ins; i++) {
		struct usb_audio_term iterm;
		len = 0;
		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
		if (! namelist[i]) {
			snd_printk(KERN_ERR "cannot malloc\n");
			while (i--)
				kfree(namelist[i]);
			kfree(namelist);
			kfree(cval);
			return -ENOMEM;
		}
		len = check_mapped_selector_name(state, unitid, i, namelist[i],
						 MAX_ITEM_NAME_LEN);
		if (! len && check_input_term(state, desc[5 + i], &iterm) >= 0)
			len = get_term_name(state, &iterm, namelist[i], MAX_ITEM_NAME_LEN, 0);
		if (! len)
			sprintf(namelist[i], "Input %d", i);
	}