alsa-project · ujfalusi · Aug 11, 2026
diff --git a/src/utils/Makefile.am b/src/utils/Makefile.am
@@ -1,12 +1,14 @@
 SUBDIRS=sofprobeclient
 
-bin_PROGRAMS = cplay crecord
+bin_PROGRAMS = cplay crecord ccaps
 
 cplay_SOURCES = cplay.c wave.c
 crecord_SOURCES = crecord.c wave.c
+ccaps_SOURCES = ccaps.c
 
 cplay_CFLAGS = -I$(top_srcdir)/include
 crecord_CFLAGS = -I$(top_srcdir)/include
+ccaps_CFLAGS = -I$(top_srcdir)/include
 
 
 cplay_LDADD = $(top_builddir)/src/lib/libtinycompress.la

diff --git a/src/utils/ccaps.c b/src/utils/ccaps.c
@@ -0,0 +1,281 @@
+/*
+ * This file is provided under a dual BSD/LGPLv2.1 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * BSD LICENSE
+ *
+ * ccaps command line capability query tool for compress audio offload in alsa
+ * Copyright (c) 2024, Intel Corporation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * Neither the name of Intel Corporation nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * LGPL LICENSE
+ *
+ * ccaps command line capability query tool for compress audio offload in alsa
+ * Copyright (c) 2024, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU Lesser General Public License,
+ * version 2.1, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to
+ * the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdint.h>
+#include <linux/types.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include <sys/ioctl.h>
+#include <config.h>
+#define __force
+#define __bitwise
+#define __user
+#include "sound/compress_params.h"
+#include "sound/compress_offload.h"
+
+static const struct {
+	const char *name;
+	unsigned int id;
+} codec_ids[] = {
+	{ "PCM", SND_AUDIOCODEC_PCM },
+	{ "MP3", SND_AUDIOCODEC_MP3 },
+	{ "AMR", SND_AUDIOCODEC_AMR },
+	{ "AMRWB", SND_AUDIOCODEC_AMRWB },
+	{ "AMRWBPLUS", SND_AUDIOCODEC_AMRWBPLUS },
+	{ "AAC", SND_AUDIOCODEC_AAC },
+	{ "WMA", SND_AUDIOCODEC_WMA },
+	{ "REAL", SND_AUDIOCODEC_REAL },
+	{ "VORBIS", SND_AUDIOCODEC_VORBIS },
+	{ "FLAC", SND_AUDIOCODEC_FLAC },
+	{ "IEC61937", SND_AUDIOCODEC_IEC61937 },
+	{ "G723_1", SND_AUDIOCODEC_G723_1 },
+	{ "G729", SND_AUDIOCODEC_G729 },
+#ifdef SND_AUDIOCODEC_BESPOKE
+	{ "BESPOKE", SND_AUDIOCODEC_BESPOKE },
+#endif
+#ifdef SND_AUDIOCODEC_ALAC
+	{ "ALAC", SND_AUDIOCODEC_ALAC },
+#endif
+#ifdef SND_AUDIOCODEC_APE
+	{ "APE", SND_AUDIOCODEC_APE },
+#endif
+};
+#define CCAPS_NUM_CODEC_IDS (sizeof(codec_ids) / sizeof(codec_ids[0]))
+
+static void usage(void)
+{
+	fprintf(stderr, "usage: ccaps [OPTIONS]\n"
+		"-c\tcard number\n"
+		"-d\tdevice node\n"
+		"-D\tdirection: p(layback) or c(apture), default is autodetect\n"
+		"-h\tPrints this help list\n\n"
+		"Example:\n"
+		"\tccaps -c 1 -d 2\n"
+		"\tccaps -c 0 -d 0 -D c\n");
+
+	exit(EXIT_FAILURE);
+}
+
+static const char *codec_name(unsigned int id)
+{
+	unsigned int i;
+
+	for (i = 0; i < CCAPS_NUM_CODEC_IDS; i++)
+		if (codec_ids[i].id == id)
+			return codec_ids[i].name;
+
+	return "UNKNOWN";
+}
+
+static const char *direction_name(unsigned int dir)
+{
+	switch (dir) {
+	case SND_COMPRESS_PLAYBACK:
+		return "playback";
+	case SND_COMPRESS_CAPTURE:
+		return "capture";
+#ifdef SND_COMPRESS_ACCEL
+	case SND_COMPRESS_ACCEL:
+		return "accel";
+#endif
+	default:
+		return "unknown";
+	}
+}
+
+static void print_u32_list(const char *label, const __u32 *values,
+			   unsigned int count, unsigned int max)
+{
+	unsigned int i;
+
+	if (count > max)
+		count = max;
+
+	printf("    %s (%u):", label, count);
+	for (i = 0; i < count; i++)
+		printf(" %u", values[i]);
+	printf("\n");
+}
+
+static void print_codec_caps(int fd, unsigned int codec)
+{
+	struct snd_compr_codec_caps ccaps;
+	unsigned int i;
+
+	memset(&ccaps, 0, sizeof(ccaps));
+	ccaps.codec = codec;
+
+	if (ioctl(fd, SNDRV_COMPRESS_GET_CODEC_CAPS, &ccaps)) {
+		printf("    no codec descriptors (%s)\n", strerror(errno));
+		return;
+	}
+
+	if (ccaps.num_descriptors > MAX_NUM_CODEC_DESCRIPTORS)
+		ccaps.num_descriptors = MAX_NUM_CODEC_DESCRIPTORS;
+
+	for (i = 0; i < ccaps.num_descriptors; i++) {
+		struct snd_codec_desc *d = &ccaps.descriptor[i];
+
+		printf("    descriptor %u:\n", i);
+		printf("      max channels: %u\n", d->max_ch);
+		print_u32_list("sample rates", d->sample_rates,
+			       d->num_sample_rates, MAX_NUM_SAMPLE_RATES);
+		print_u32_list("bit rates", d->bit_rate,
+			       d->num_bitrates, MAX_NUM_BITRATES);
+		printf("      rate control: 0x%08x%s%s\n", d->rate_control,
+		       (d->rate_control & SND_RATECONTROLMODE_CONSTANTBITRATE) ? " CBR" : "",
+		       (d->rate_control & SND_RATECONTROLMODE_VARIABLEBITRATE) ? " VBR" : "");
+		printf("      profiles:     0x%08x\n", d->profiles);
+		printf("      modes:        0x%08x\n", d->modes);
+		printf("      formats:      0x%08x\n", d->formats);
+		printf("      min buffer:   %u\n", d->min_buffer);
+	}
+}
+
+static int open_device(unsigned int card, unsigned int device, int dir_flags)
+{
+	char fn[256];
+	int fd;
+
+	snprintf(fn, sizeof(fn), "/dev/snd/comprC%uD%u", card, device);
+
+	if (dir_flags != -1)
+		return open(fn, dir_flags);
+
+	/* autodetect: the kernel derives the stream direction from the flags */
+	fd = open(fn, O_WRONLY);
+	if (fd < 0)
+		fd = open(fn, O_RDONLY);
+
+	return fd;
+}
+
+int main(int argc, char **argv)
+{
+	struct snd_compr_caps caps;
+	unsigned int card = 0, device = 0;
+	int dir_flags = -1;
+	int version = 0;
+	unsigned int i;
+	int c, fd;
+
+	while ((c = getopt(argc, argv, "hc:d:D:")) != -1) {
+		switch (c) {
+		case 'h':
+			usage();
+			break;
+		case 'c':
+			card = strtol(optarg, NULL, 10);
+			break;
+		case 'd':
+			device = strtol(optarg, NULL, 10);
+			break;
+		case 'D':
+			if (optarg[0] == 'p')
+				dir_flags = O_WRONLY;
+			else if (optarg[0] == 'c')
+				dir_flags = O_RDONLY;
+			else
+				usage();
+			break;
+		default:
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	fd = open_device(card, device, dir_flags);
+	if (fd < 0) {
+		fprintf(stderr, "Unable to open /dev/snd/comprC%uD%u: %s\n",
+			card, device, strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	if (ioctl(fd, SNDRV_COMPRESS_IOCTL_VERSION, &version))
+		fprintf(stderr, "Unable to read protocol version: %s\n",
+			strerror(errno));
+
+	memset(&caps, 0, sizeof(caps));
+	if (ioctl(fd, SNDRV_COMPRESS_GET_CAPS, &caps)) {
+		fprintf(stderr, "Unable to get device caps: %s\n", strerror(errno));
+		close(fd);
+		exit(EXIT_FAILURE);
+	}
+
+	if (caps.num_codecs > MAX_NUM_CODECS)
+		caps.num_codecs = MAX_NUM_CODECS;
+
+	printf("Compress device hw:%u,%u\n", card, device);
+	printf("  protocol version:  %d.%d.%d\n",
+	       (version >> 16) & 0xffff, (version >> 8) & 0xff, version & 0xff);
+	printf("  direction:         %s\n", direction_name(caps.direction));
+	printf("  fragment size:     %u - %u bytes\n",
+	       caps.min_fragment_size, caps.max_fragment_size);
+	printf("  fragments:         %u - %u\n",
+	       caps.min_fragments, caps.max_fragments);
+	printf("  codecs:            %u\n", caps.num_codecs);
+
+	for (i = 0; i < caps.num_codecs; i++) {
+		printf("  [%u] %s (0x%x)\n", i, codec_name(caps.codecs[i]),
+		       caps.codecs[i]);
+		print_codec_caps(fd, caps.codecs[i]);
+	}
+
+	close(fd);
+	exit(EXIT_SUCCESS);
+}