[alsa-devel] [PATCH] usb_stream alsa-plugin
Karsten Wiese
fzu at wemgehoertderstaat.de
Tue May 20 11:45:49 CEST 2008
Establishes pcm i/o for the snd_usb_us122l module.
Needs below section to be a part of ~/.asoundrc:
# The usb_stream plugin configuration
pcm.!usb_stream {
@args [ CARD ]
@args.CARD {
type string
default "0"
}
type usb_stream
card $CARD
}
Example loop command:
$ ARGS="-MDusb_stream:2 -fS24_3LE -r44100 -c2 --period-size=640" ; arecord $ARGS | aplay $ARGS
Signed-off-by: Karsten Wiese <fzu at wemgehoertderstaat.de>
---
diff -NpurX /home/ka/diff_exc alsa-plugins-1.0.15/configure.in alsa-plugins-1.0.15+usb_stream/configure.in
--- alsa-plugins-1.0.15/configure.in 2008-03-22 18:43:36.000000000 +0100
+++ alsa-plugins-1.0.15+usb_stream/configure.in 2008-03-16 18:07:17.000000000 +0100
@@ -111,6 +111,7 @@ AC_OUTPUT([
rate-lavc/Makefile
maemo/Makefile
doc/Makefile
+ usb_stream/Makefile
])
dnl Show the build conditions
diff -NpurX /home/ka/diff_exc alsa-plugins-1.0.15/Makefile.am alsa-plugins-1.0.15+usb_stream/Makefile.am
--- alsa-plugins-1.0.15/Makefile.am 2008-03-22 18:43:00.000000000 +0100
+++ alsa-plugins-1.0.15+usb_stream/Makefile.am 2008-03-12 00:55:25.000000000 +0100
@@ -18,7 +18,7 @@ if HAVE_PPH
PPHDIR = pph
endif
-SUBDIRS = oss mix $(PPHDIR) $(JACKDIR) $(PULSEDIR) $(SAMPLERATEDIR) $(A52DIR) $(LAVCRATEDIR) $(MAEMODIR) doc
+SUBDIRS = oss mix $(PPHDIR) $(JACKDIR) $(PULSEDIR) $(SAMPLERATEDIR) $(A52DIR) $(LAVCRATEDIR) $(MAEMODIR) usb_stream doc
EXTRA_DIST = hgcompile version COPYING.GPL
AUTOMAKE_OPTIONS = foreign
diff -NpurX /home/ka/diff_exc alsa-plugins-1.0.15/usb_stream/Makefile.am alsa-plugins-1.0.15+usb_stream/usb_stream/Makefile.am
--- alsa-plugins-1.0.15/usb_stream/Makefile.am 1970-01-01 01:00:00.000000000 +0100
+++ alsa-plugins-1.0.15+usb_stream/usb_stream/Makefile.am 2008-03-07 23:23:59.000000000 +0100
@@ -0,0 +1,9 @@
+asound_module_pcm_usb_stream_LTLIBRARIES = libasound_module_pcm_usb_stream.la
+
+asound_module_pcm_usb_streamdir = @ALSA_PLUGIN_DIR@
+
+AM_CFLAGS = -Wall -g @ALSA_CFLAGS@
+AM_LDFLAGS = -module -avoid-version -export-dynamic
+
+libasound_module_pcm_usb_stream_la_SOURCES = pcm_usb_stream.c
+libasound_module_pcm_usb_stream_la_LIBADD = @ALSA_LIBS@
diff -NpurX /home/ka/diff_exc alsa-plugins-1.0.15/usb_stream/pcm_usb_stream.c alsa-plugins-1.0.15+usb_stream/usb_stream/pcm_usb_stream.c
--- alsa-plugins-1.0.15/usb_stream/pcm_usb_stream.c 1970-01-01 01:00:00.000000000 +0100
+++ alsa-plugins-1.0.15+usb_stream/usb_stream/pcm_usb_stream.c 2008-05-18 12:06:07.000000000 +0200
@@ -0,0 +1,485 @@
+/*
+ * PCM - USB_STREAM plugin
+ *
+ * Copyright (c) 2008 by Karsten Wiese <fzu at wemgehoertderstaat.de>
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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 library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <byteswap.h>
+#define _GNU_SOURCE
+#include <sys/mman.h>
+#include <sys/shm.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <pthread.h>
+
+#include <alsa/asoundlib.h>
+#include <alsa/pcm_external.h>
+#include <alsa/hwdep.h>
+
+// FIXME: better way needed to include the kernel's sound/usb/usx2y/usb_stream.h
+#include "/lib/modules/2.6.25.4/source/sound/usb/usx2y/usb_stream.h"
+
+#define DEBUG
+#ifdef DEBUG
+#define DBG(f, ...) \
+ fprintf(stderr, "%s:%i %i "f"\n", __FUNCTION__, __LINE__, getpid(), ## __VA_ARGS__);
+#else
+#define DBG(f, ...)
+#endif
+
+#ifdef VDEBUG
+#define VDBG(f, ...) \
+ fprintf(stderr, "%s:%i %i "f"\n", __FUNCTION__, __LINE__, getpid(), ## __VA_ARGS__);
+#else
+#define VDBG(f, ...)
+#endif
+
+#define LCARD 32
+struct user_usb_stream {
+ char card[LCARD];
+ unsigned use;
+ struct usb_stream *s;
+ void *write_area;
+ struct user_usb_stream *next;
+};
+
+typedef struct {
+ snd_pcm_ioplug_t io;
+
+ snd_hwdep_t *hwdep;
+ struct user_usb_stream *uus;
+
+ struct pollfd pfd;
+
+ unsigned int num_ports;
+ unsigned periods_start;
+ unsigned periods_done;
+
+ unsigned channels;
+} snd_pcm_us_t;
+
+static struct user_usb_stream *uus;
+static pthread_mutex_t uus_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+struct user_usb_stream *get_uus(const char *card)
+{
+ pthread_mutex_lock(&uus_mutex);
+
+ struct user_usb_stream **l_uus = &uus,
+ *r_uus = NULL;
+ while (*l_uus) {
+ if (strcmp((*l_uus)->card, card) == 0) {
+ r_uus = *l_uus;
+ r_uus->use++;
+ goto unlock;
+ }
+ l_uus = &(*l_uus)->next;
+ }
+ r_uus = calloc(1, sizeof(*r_uus));
+ if (r_uus) {
+ r_uus->use = 1;
+ strcpy(r_uus->card, card);
+ *l_uus = r_uus;
+ }
+
+unlock:
+ pthread_mutex_unlock(&uus_mutex);
+ return r_uus;
+}
+
+static void uus_free(snd_pcm_us_t *us)
+{
+ if (!us->uus)
+ return;
+
+ pthread_mutex_lock(&uus_mutex);
+ us->uus->use--;
+ if (!us->uus->use) {
+ struct user_usb_stream **n_uus = &uus,
+ *p_uus;
+ while (us->uus != *n_uus) {
+ p_uus = *n_uus;
+ n_uus = &p_uus->next;
+ }
+ *n_uus = us->uus->next;
+ if (us->uus->s) {
+ munmap(us->uus->write_area, us->uus->s->write_size);
+ munmap(us->uus->s, us->uus->s->read_size);
+ }
+ free(us->uus);
+ }
+ pthread_mutex_unlock(&uus_mutex);
+}
+
+static void us_free(snd_pcm_us_t *us)
+{
+ uus_free(us);
+ free(us);
+}
+
+static int snd_pcm_us_close(snd_pcm_ioplug_t *io)
+{
+ snd_pcm_us_t *us = io->private_data;
+ snd_hwdep_close(us->hwdep);
+ us_free(us);
+ return 0;
+}
+
+static snd_pcm_sframes_t snd_pcm_us_pointer(snd_pcm_ioplug_t *io)
+{
+ snd_pcm_us_t *us = io->private_data;
+ struct usb_stream *s = us->uus->s;
+ snd_pcm_sframes_t hw_pointer;
+
+ switch (io->state) {
+ case SND_PCM_STATE_RUNNING:
+ VDBG("%u %u", s->periods_done, us->periods_done);
+ if (s->periods_done - us->periods_done <= 1)
+ hw_pointer =
+ (s->periods_done - us->periods_start) & 1 ?
+ io->period_size : 0;
+ else
+ hw_pointer = -EPIPE;
+
+ break;
+ case SND_PCM_STATE_XRUN:
+ hw_pointer = -EPIPE;
+ break;
+ default:
+ hw_pointer = 0;
+ break;
+ }
+ VDBG("%li", hw_pointer);
+ return hw_pointer;
+}
+
+static int snd_pcm_us_prepare(snd_pcm_ioplug_t *io)
+{
+ struct usb_stream_config us_cfg;
+ snd_pcm_us_t *us = io->private_data;
+ struct user_usb_stream *uus = us->uus;
+ int ioctl_result, err;
+
+ VDBG("");
+
+ us_cfg.version = USB_STREAM_INTERFACE_VERSION;
+ us_cfg.frame_size = 6;
+ us_cfg.sample_rate = io->rate;
+ us_cfg.period_frames = io->period_size;
+
+ ioctl_result = snd_hwdep_ioctl(us->hwdep, SNDRV_USB_STREAM_IOCTL_SET_PARAMS, &us_cfg);
+ if (ioctl_result < 0) {
+ perror("Couldn't configure usb_stream\n");
+ return ioctl_result;
+ }
+
+ if (ioctl_result && uus && uus->s) {
+ err = munmap(uus->write_area, uus->s->write_size);
+ if (err < 0)
+ return -errno;
+ err = munmap(uus->s, uus->s->read_size);
+ if (err < 0)
+ return -errno;
+ uus->s = NULL;
+ }
+
+ if (!uus->s) {
+ uus->s = mmap(NULL, sizeof(struct usb_stream),
+ PROT_READ,
+ MAP_SHARED, us->pfd.fd,
+ 0);
+ if (MAP_FAILED == uus->s) {
+ perror("ALSA/USX2Y: mmap");
+ return -errno;
+ }
+
+ VDBG("%p %lx %i", uus->s, uus->s, uus->s->read_size);
+
+ if (memcmp(&uus->s->cfg, &us_cfg, sizeof(us_cfg))) {
+ perror("usb_stream Configuration error usb_stream\n");
+ return -EIO;
+ }
+
+
+ uus->s = mremap(uus->s, sizeof(struct usb_stream), uus->s->read_size, MREMAP_MAYMOVE);
+ if (MAP_FAILED == uus->s) {
+ perror("ALSA/USX2Y: mmap");
+ return -EPERM;
+ }
+
+ VDBG("%p %lx %i", uus->s, uus->s, uus->s->read_size);
+
+ uus->write_area = mmap(NULL, uus->s->write_size,
+ PROT_READ|PROT_WRITE,
+ MAP_SHARED, us->pfd.fd,
+ (uus->s->read_size + 4095) & ~4095);
+ if (MAP_FAILED == uus->write_area) {
+ perror("ALSA/USX2Y: mmap");
+ return -1;
+ }
+ VDBG("%p %i", uus->write_area, uus->s->write_size);
+ }
+
+ if (uus->s->state != usb_stream_ready)
+ return -EIO;
+
+ if (poll(&us->pfd, 1, 500000) < 0)
+ return -errno;
+
+ return 0;
+}
+
+static int snd_pcm_us_start(snd_pcm_ioplug_t *io)
+{
+ snd_pcm_us_t *us = io->private_data;
+ VDBG("%u", us->uus->s->periods_done);
+
+ us->periods_start = us->periods_done = us->uus->s->periods_done;
+
+ return 0;
+}
+
+static int snd_pcm_us_stop(snd_pcm_ioplug_t *io)
+{
+ snd_pcm_us_t *us = io->private_data;
+ VDBG("%u", us->uus->s->periods_done);
+
+ if (io->stream == SND_PCM_STREAM_PLAYBACK)
+ memset(us->uus->write_area, 0, us->uus->s->write_size);
+
+ return 0;
+}
+
+static snd_pcm_sframes_t snd_pcm_us_write(snd_pcm_ioplug_t *io,
+ const snd_pcm_channel_area_t *areas,
+ snd_pcm_uframes_t offset,
+ snd_pcm_uframes_t size)
+{
+ void *playback_addr;
+ snd_pcm_us_t *us = io->private_data;
+ struct user_usb_stream *uus = us->uus;
+ struct usb_stream *s = uus->s;
+ unsigned bytes;
+ void *src = areas->addr + offset * s->cfg.frame_size;
+
+ VDBG("%li %li %i %i", offset, size, areas->first, areas->step);
+
+ playback_addr = uus->write_area + s->outpacket[0].offset;
+ memcpy(playback_addr, src, s->outpacket[0].length);
+ bytes = size * s->cfg.frame_size;
+ if (bytes > s->outpacket[0].length) {
+ playback_addr = uus->write_area + s->outpacket[1].offset;
+ memcpy(playback_addr, src + s->outpacket[0].length,
+ bytes - s->outpacket[0].length);
+ }
+ us->periods_done++;
+ return size;
+}
+
+static int usb_stream_read(struct user_usb_stream *uus, void *to, unsigned bytes)
+{
+ struct usb_stream *s = uus->s;
+ int p = s->inpacket_split, l = 0;
+ void *i = (void *)s + s->inpacket[p].offset + s->inpacket_split_at;
+ int il = s->inpacket[p].length - s->inpacket_split_at;
+
+ do {
+ if (l + il > s->period_size)
+ il = s->period_size - l;
+ memcpy(to + l, i, il);
+ l += il;
+ if (l >= s->period_size)
+ break;
+
+ p = (p + 1) % s->inpackets;
+ i = (void *)s + s->inpacket[p].offset;
+ il = s->inpacket[p].length;
+ } while (p != s->inpacket_split);
+
+ return l;
+}
+
+static snd_pcm_sframes_t snd_pcm_us_read(snd_pcm_ioplug_t *io,
+ const snd_pcm_channel_area_t *areas,
+ snd_pcm_uframes_t offset,
+ snd_pcm_uframes_t size)
+{
+ snd_pcm_us_t *us = io->private_data;
+ unsigned frame_size = us->uus->s->cfg.frame_size;
+ void *to = areas->addr + offset * frame_size;
+ snd_pcm_uframes_t red;
+
+ if (size) {
+ if (size != us->uus->s->cfg.period_frames) {
+ SNDERR("usb_stream plugin only supports period_size"
+ " long reads, sorry");
+ return -EINVAL;
+ }
+ if (us->uus->s->periods_done - us->periods_done == 1) {
+ red = usb_stream_read(us->uus, to, size * frame_size) /
+ frame_size;
+ us->periods_done++;
+ return red;
+ }
+ } else
+ if (io->state == SND_PCM_STATE_XRUN)
+ return -EPIPE;
+ return 0;
+}
+
+static snd_pcm_ioplug_callback_t us_playback_callback = {
+ .close = snd_pcm_us_close,
+ .start = snd_pcm_us_start,
+ .stop = snd_pcm_us_stop,
+ .transfer = snd_pcm_us_write,
+ .pointer = snd_pcm_us_pointer,
+ .prepare = snd_pcm_us_prepare,
+};
+static snd_pcm_ioplug_callback_t us_capture_callback = {
+ .close = snd_pcm_us_close,
+ .start = snd_pcm_us_start,
+ .stop = snd_pcm_us_stop,
+ .transfer = snd_pcm_us_read,
+ .pointer = snd_pcm_us_pointer,
+ .prepare = snd_pcm_us_prepare,
+};
+
+#define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
+
+static int us_set_hw_constraint(snd_pcm_us_t *us)
+{
+ unsigned access_list[] = {
+ SND_PCM_ACCESS_MMAP_INTERLEAVED,
+ };
+ unsigned format_list[] = {
+ SND_PCM_FORMAT_S24_3LE,
+ };
+
+ int err;
+
+ if ((err = snd_pcm_ioplug_set_param_list(&us->io, SND_PCM_IOPLUG_HW_ACCESS,
+ ARRAY_SIZE(access_list), access_list)) < 0 ||
+ (err = snd_pcm_ioplug_set_param_list(&us->io, SND_PCM_IOPLUG_HW_FORMAT,
+ ARRAY_SIZE(format_list), format_list)) < 0 ||
+ (err = snd_pcm_ioplug_set_param_minmax(&us->io, SND_PCM_IOPLUG_HW_CHANNELS,
+ us->channels, us->channels)) < 0 ||
+ (err = snd_pcm_ioplug_set_param_minmax(&us->io, SND_PCM_IOPLUG_HW_RATE,
+ 44100, 96000)) < 0 ||
+ (err = snd_pcm_ioplug_set_param_minmax(&us->io, SND_PCM_IOPLUG_HW_PERIOD_BYTES,
+ 128, 64*4096)) < 0 ||
+ (err = snd_pcm_ioplug_set_param_minmax(&us->io, SND_PCM_IOPLUG_HW_PERIODS,
+ 2, 2)) < 0)
+ return err;
+
+ return 0;
+}
+
+static int snd_pcm_us_open(snd_pcm_t **pcmp, const char *name,
+ const char *card,
+ snd_pcm_stream_t stream, int mode)
+{
+ snd_pcm_us_t *us;
+ int err;
+ char us_name[32];
+
+ if (strlen(card) >= LCARD)
+ return -EINVAL;
+
+ assert(pcmp);
+ us = calloc(1, sizeof(*us));
+ if (!us)
+ return -ENOMEM;
+
+ if (snprintf(us_name, sizeof(us_name), "hw:%s", card)
+ >= (int)sizeof(us_name)) {
+ fprintf(stderr, "%s: WARNING: USB_STREAM client name '%s' truncated to %d characters, might not be unique\n",
+ __func__, us_name, (int)strlen(us_name));
+ }
+ VDBG("%i %s", stream, us_name);
+ us->uus = get_uus(card);
+ if (!us->uus)
+ return -ENOMEM;
+ err = snd_hwdep_open(&us->hwdep, us_name, O_RDWR);
+ if (err < 0) {
+ us_free(us);
+ return err;
+ }
+ snd_hwdep_poll_descriptors(us->hwdep, &us->pfd, 1);
+
+ us->channels = 2;
+
+ us->io.version = SND_PCM_IOPLUG_VERSION;
+ us->io.name = "ALSA <-> USB_STREAM PCM I/O Plugin";
+ us->io.callback = stream == SND_PCM_STREAM_PLAYBACK ?
+ &us_playback_callback : &us_capture_callback;
+ us->io.private_data = us;
+ us->io.mmap_rw = 0;
+ us->io.poll_fd = us->pfd.fd;
+ us->io.poll_events = stream == SND_PCM_STREAM_PLAYBACK ? POLLOUT : POLLIN;
+
+ err = snd_pcm_ioplug_create(&us->io, name, stream, mode);
+ if (err < 0) {
+ us_free(us);
+ return err;
+ }
+
+ err = us_set_hw_constraint(us);
+ if (err < 0) {
+ snd_pcm_ioplug_delete(&us->io);
+ return err;
+ }
+
+ VDBG("");
+ *pcmp = us->io.pcm;
+
+ return 0;
+}
+
+
+SND_PCM_PLUGIN_DEFINE_FUNC(usb_stream)
+{
+ snd_config_iterator_t i, next;
+ const char *card;
+ int err;
+
+ snd_config_for_each(i, next, conf) {
+ snd_config_t *n = snd_config_iterator_entry(i);
+ const char *id;
+ if (snd_config_get_id(n, &id) < 0)
+ continue;
+
+ if (strcmp(id, "comment") == 0 || strcmp(id, "type") == 0)
+ continue;
+ if (strcmp(id, "card") == 0) {
+ if (snd_config_get_type(n) != SND_CONFIG_TYPE_STRING) {
+ SNDERR("Invalid type for %s", id);
+ return -EINVAL;
+ }
+ snd_config_get_string(n, &card);
+ continue;
+ }
+ SNDERR("Unknown field %s", id);
+ return -EINVAL;
+ }
+
+ err = snd_pcm_us_open(pcmp, name, card, stream, mode);
+
+ return err;
+}
+
+SND_PCM_PLUGIN_SYMBOL(usb_stream);
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