Commit dcbe7bcf authored by Daniel Mack's avatar Daniel Mack Committed by Takashi Iwai
Browse files

ALSA: usb-audio: UAC2: clean up parsing of bmaControls 



Introduce two new static inline functions for a more readable parsing
of UAC2 bmaControls.

Signed-off-by: default avatarDaniel Mack <daniel@caiaq.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 67a3e12b

include/linux/usb/audio-v2.h

+10 −0
Original line number Diff line number Diff line
@@ -18,6 +18,16 @@ 
/* v1.0 and v2.0 of this standard have many things in common. For the rest

 * of the definitions, please refer to audio.h */



static inline bool uac2_control_is_readable(u32 bmControls, u8 control)

{

	return (bmControls >> (control * 2)) & 0x1;

}



static inline bool uac2_control_is_writeable(u32 bmControls, u8 control)

{

	return (bmControls >> (control * 2)) & 0x2;

}



/* 4.7.2.1 Clock Source Descriptor */



struct uac_clock_source_descriptor {

sound/usb/mixer.c

+4 −4
Original line number Diff line number Diff line
@@ -1188,9 +1188,9 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void 


			for (j = 0; j < channels; j++) {

				unsigned int mask = snd_usb_combine_bytes(bmaControls + csize * (j+1), csize);

				if (mask & (1 << (i * 2))) {

				if (uac2_control_is_readable(mask, i)) {

					ch_bits |= (1 << j);

					if (~mask & (1 << ((i * 2) + 1)))

					if (!uac2_control_is_writeable(mask, i))

						ch_read_only |= (1 << j);

				}

			}
@@ -1198,9 +1198,9 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void 
			/* FIXME: the whole unit is read-only if any of the channels is marked read-only */

			if (ch_bits & 1) /* the first channel must be set (for ease of programming) */

				build_feature_ctl(state, _ftr, ch_bits, i, &iterm, unitid, !!ch_read_only);

			if (master_bits & (1 << i * 2))

			if (uac2_control_is_readable(master_bits, i))

				build_feature_ctl(state, _ftr, 0, i, &iterm, unitid,

						  ~master_bits & (1 << ((i * 2) + 1)));

						  !uac2_control_is_writeable(master_bits, i));

		}

	}