Commit e0ccdef9 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: usb-audio: Clean up check_input_term() 



The primary changes in this patch are cleanups of __check_input_term()
and move to a non-nested switch-case block by evaluating the pair of
UAC version and the unit type, as we've done for parse_audio_unit().
Also each parser is split into the function for readability.

Now, a slight behavior change by this cleanup is the handling of
processing and extension units.  Formerly we've dealt with them
differently between UAC1/2 and UAC3; the latter returns an error if no
input sources are available, while the former continues to parse.

In this patch, unify the behavior in all cases: when input sources are
available, it parses recursively, then override the type and the id,
as well as channel information if not provided yet.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 744f51e8

sound/usb/mixer.c

+209 −192
Original line number Diff line number Diff line
@@ -758,151 +758,62 @@ static int uac_mixer_unit_get_channels(struct mixer_build *state, 
}



/*

 * parse the source unit recursively until it reaches to a terminal

 * or a branched unit.

 * Parse Input Terminal Unit

 */

static int __check_input_term(struct mixer_build *state, int id,

			    struct usb_audio_term *term)

{

	int protocol = state->mixer->protocol;

	int err;

	void *p1;

	unsigned char *hdr;



	memset(term, 0, sizeof(*term));

	for (;;) {

		/* a loop in the terminal chain? */

		if (test_and_set_bit(id, state->termbitmap))

			return -EINVAL;



		p1 = find_audio_control_unit(state, id);

		if (!p1)

			break;

		if (!snd_usb_validate_audio_desc(p1, protocol))

			break; /* bad descriptor */

			      struct usb_audio_term *term);



		hdr = p1;

		term->id = id;



		if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {

			switch (hdr[2]) {

			case UAC_INPUT_TERMINAL:

				if (protocol == UAC_VERSION_1) {

static int parse_term_uac1_iterm_unit(struct mixer_build *state,

				      struct usb_audio_term *term,

				      void *p1, int id)

{

	struct uac_input_terminal_descriptor *d = p1;



	term->type = le16_to_cpu(d->wTerminalType);

	term->channels = d->bNrChannels;

	term->chconfig = le16_to_cpu(d->wChannelConfig);

	term->name = d->iTerminal;

				} else { /* UAC_VERSION_2 */

	return 0;

}



static int parse_term_uac2_iterm_unit(struct mixer_build *state,

				      struct usb_audio_term *term,

				      void *p1, int id)

{

	struct uac2_input_terminal_descriptor *d = p1;

	int err;



					/* call recursively to verify that the

					 * referenced clock entity is valid */

	/* call recursively to verify the referenced clock entity */

	err = __check_input_term(state, d->bCSourceID, term);

	if (err < 0)

		return err;



	/* save input term properties after recursion,

					 * to ensure they are not overriden by the

					 * recursion calls */

	 * to ensure they are not overriden by the recursion calls

	 */

	term->id = id;

	term->type = le16_to_cpu(d->wTerminalType);

	term->channels = d->bNrChannels;

	term->chconfig = le32_to_cpu(d->bmChannelConfig);

	term->name = d->iTerminal;

				}

	return 0;

			case UAC_FEATURE_UNIT: {

				/* the header is the same for v1 and v2 */

				struct uac_feature_unit_descriptor *d = p1;



				id = d->bSourceID;

				break; /* continue to parse */

}

			case UAC_MIXER_UNIT: {

				struct uac_mixer_unit_descriptor *d = p1;



				term->type = UAC3_MIXER_UNIT << 16; /* virtual type */

				term->channels = uac_mixer_unit_bNrChannels(d);

				term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);

				term->name = uac_mixer_unit_iMixer(d);

				return 0;

			}

			case UAC_SELECTOR_UNIT:

			case UAC2_CLOCK_SELECTOR: {

				struct uac_selector_unit_descriptor *d = p1;

				/* call recursively to retrieve the channel info */

				err = __check_input_term(state, d->baSourceID[0], term);

				if (err < 0)

					return err;

				term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */

				term->id = id;

				term->name = uac_selector_unit_iSelector(d);

				return 0;

			}

			case UAC1_PROCESSING_UNIT:

			/* UAC2_EFFECT_UNIT */

				if (protocol == UAC_VERSION_1)

					term->type = UAC3_PROCESSING_UNIT << 16; /* virtual type */

				else /* UAC_VERSION_2 */

					term->type = UAC3_EFFECT_UNIT << 16; /* virtual type */

				/* fall through */

			case UAC1_EXTENSION_UNIT:

			/* UAC2_PROCESSING_UNIT_V2 */

				if (protocol == UAC_VERSION_1 && !term->type)

					term->type = UAC3_EXTENSION_UNIT << 16; /* virtual type */

				else if (protocol == UAC_VERSION_2 && !term->type)

					term->type = UAC3_PROCESSING_UNIT << 16; /* virtual type */

				/* fall through */

			case UAC2_EXTENSION_UNIT_V2: {

				struct uac_processing_unit_descriptor *d = p1;



				if (protocol == UAC_VERSION_2 &&

					hdr[2] == UAC2_EFFECT_UNIT) {

					/* UAC2/UAC1 unit IDs overlap here in an

					 * uncompatible way. Ignore this unit for now.

					 */

					return 0;

				}



				if (d->bNrInPins) {

					id = d->baSourceID[0];

					break; /* continue to parse */

				}

				if (!term->type)

					term->type = UAC3_EXTENSION_UNIT << 16; /* virtual type */



				term->channels = uac_processing_unit_bNrChannels(d);

				term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);

				term->name = uac_processing_unit_iProcessing(d, protocol);

				return 0;

			}

			case UAC2_CLOCK_SOURCE: {

				struct uac_clock_source_descriptor *d = p1;



				term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */

				term->id = id;

				term->name = d->iClockSource;

				return 0;

			}

			default:

				return -ENODEV;

			}

		} else { /* UAC_VERSION_3 */

			switch (hdr[2]) {

			case UAC_INPUT_TERMINAL: {

static int parse_term_uac3_iterm_unit(struct mixer_build *state,

				      struct usb_audio_term *term,

				      void *p1, int id)

{

	struct uac3_input_terminal_descriptor *d = p1;

	int err;



				/* call recursively to verify that the

				 * referenced clock entity is valid */

	/* call recursively to verify the referenced clock entity */

	err = __check_input_term(state, d->bCSourceID, term);

	if (err < 0)

		return err;



	/* save input term properties after recursion,

				 * to ensure they are not overriden by the

				 * recursion calls */

	 * to ensure they are not overriden by the recursion calls

	 */

	term->id = id;

	term->type = le16_to_cpu(d->wTerminalType);
@@ -917,67 +828,174 @@ static int __check_input_term(struct mixer_build *state, int id, 
	term->name = le16_to_cpu(d->wTerminalDescrStr);

	return 0;

}

			case UAC3_FEATURE_UNIT: {

				struct uac3_feature_unit_descriptor *d = p1;



				id = d->bSourceID;

				break; /* continue to parse */

			}

			case UAC3_CLOCK_SOURCE: {

				struct uac3_clock_source_descriptor *d = p1;



				term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */

				term->id = id;

				term->name = le16_to_cpu(d->wClockSourceStr);

				return 0;

			}

			case UAC3_MIXER_UNIT: {

static int parse_term_mixer_unit(struct mixer_build *state,

				 struct usb_audio_term *term,

				 void *p1, int id)

{

	struct uac_mixer_unit_descriptor *d = p1;

	int protocol = state->mixer->protocol;

	int err;



	err = uac_mixer_unit_get_channels(state, d);

	if (err <= 0)

		return err;



				term->channels = err;

	term->type = UAC3_MIXER_UNIT << 16; /* virtual type */



	term->channels = err;

	if (protocol != UAC_VERSION_3) {

		term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);

		term->name = uac_mixer_unit_iMixer(d);

	}

	return 0;

}

			case UAC3_SELECTOR_UNIT:

			case UAC3_CLOCK_SELECTOR: {



static int parse_term_selector_unit(struct mixer_build *state,

				    struct usb_audio_term *term,

				    void *p1, int id)

{

	struct uac_selector_unit_descriptor *d = p1;

	int err;



	/* call recursively to retrieve the channel info */

	err = __check_input_term(state, d->baSourceID[0], term);

	if (err < 0)

		return err;

	term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */

	term->id = id;

				term->name = 0; /* TODO: UAC3 Class-specific strings */



	if (state->mixer->protocol != UAC_VERSION_3)

		term->name = uac_selector_unit_iSelector(d);

	return 0;

}

			case UAC3_PROCESSING_UNIT: {

				struct uac_processing_unit_descriptor *d = p1;



				if (!d->bNrInPins)

					return -EINVAL;

static int parse_term_proc_unit(struct mixer_build *state,

				struct usb_audio_term *term,

				void *p1, int id, int vtype)

{

	struct uac_processing_unit_descriptor *d = p1;

	int protocol = state->mixer->protocol;

	int err;



	if (d->bNrInPins) {

		/* call recursively to retrieve the channel info */

		err = __check_input_term(state, d->baSourceID[0], term);

		if (err < 0)

			return err;

	}



	term->type = vtype << 16; /* virtual type */

	term->id = id;



	if (protocol == UAC_VERSION_3)

		return 0;



	if (!term->channels) {

		term->channels = uac_processing_unit_bNrChannels(d);

		term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);

	}

	term->name = uac_processing_unit_iProcessing(d, protocol);

	return 0;

}



				term->type = UAC3_PROCESSING_UNIT << 16; /* virtual type */

static int parse_term_uac2_clock_source(struct mixer_build *state,

					struct usb_audio_term *term,

					void *p1, int id)

{

	struct uac_clock_source_descriptor *d = p1;



	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */

	term->id = id;

				term->name = 0; /* TODO: UAC3 Class-specific strings */

	term->name = d->iClockSource;

	return 0;

}



static int parse_term_uac3_clock_source(struct mixer_build *state,

					struct usb_audio_term *term,

					void *p1, int id)

{

	struct uac3_clock_source_descriptor *d = p1;



	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */

	term->id = id;

	term->name = le16_to_cpu(d->wClockSourceStr);

	return 0;

}



#define PTYPE(a, b)	((a) << 8 | (b))



/*

 * 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)

{

	int protocol = state->mixer->protocol;

	void *p1;

	unsigned char *hdr;



	for (;;) {

		/* a loop in the terminal chain? */

		if (test_and_set_bit(id, state->termbitmap))

			return -EINVAL;



		p1 = find_audio_control_unit(state, id);

		if (!p1)

			break;

		if (!snd_usb_validate_audio_desc(p1, protocol))

			break; /* bad descriptor */



		hdr = p1;

		term->id = id;



		switch (PTYPE(protocol, hdr[2])) {

		case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):

		case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):

		case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT): {

			/* the header is the same for all versions */

			struct uac_feature_unit_descriptor *d = p1;



			id = d->bSourceID;

			break; /* continue to parse */

		}

		case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):

			return parse_term_uac1_iterm_unit(state, term, p1, id);

		case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):

			return parse_term_uac2_iterm_unit(state, term, p1, id);

		case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):

			return parse_term_uac3_iterm_unit(state, term, p1, id);

		case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):

		case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):

		case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):

			return parse_term_mixer_unit(state, term, p1, id);

		case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):

		case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):

		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):

		case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):

		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):

			return parse_term_selector_unit(state, term, p1, id);

		case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):

		case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):

		case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):

			return parse_term_proc_unit(state, term, p1, id,

						    UAC3_PROCESSING_UNIT);

		case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):

		case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):

			return parse_term_proc_unit(state, term, p1, id,

						    UAC3_EFFECT_UNIT);

		case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):

		case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):

		case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):

			return parse_term_proc_unit(state, term, p1, id,

						    UAC3_EXTENSION_UNIT);

		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):

			return parse_term_uac2_clock_source(state, term, p1, id);

		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):

			return parse_term_uac3_clock_source(state, term, p1, id);

		default:

			return -ENODEV;

		}

	}

	}

	return -ENODEV;

}
@@ -2712,7 +2730,6 @@ static int parse_audio_unit(struct mixer_build *state, int unitid) 
		return 0; /* skip invalid unit */

	}



#define PTYPE(a, b)	((a) << 8 | (b))

	switch (PTYPE(protocol, p1[2])) {

	case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):

	case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):

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