2 This file is part of PulseAudio.
4 Copyright 2009 Lennart Poettering
6 PulseAudio is free software; you can redistribute it and/or modify
7 it under the terms of the GNU Lesser General Public License as
8 published by the Free Software Foundation; either version 2.1 of the
9 License, or (at your option) any later version.
11 PulseAudio is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with PulseAudio; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
29 #include <sys/inotify.h>
32 #include <pulse/timeval.h>
34 #include <pulsecore/modargs.h>
35 #include <pulsecore/core-error.h>
36 #include <pulsecore/core-util.h>
37 #include <pulsecore/namereg.h>
38 #include <pulsecore/ratelimit.h>
40 #include "module-udev-detect-symdef.h"
42 PA_MODULE_AUTHOR("Lennart Poettering");
43 PA_MODULE_DESCRIPTION("Detect available audio hardware and load matching drivers");
44 PA_MODULE_VERSION(PACKAGE_VERSION);
45 PA_MODULE_LOAD_ONCE(TRUE);
47 "tsched=<enable system timer based scheduling mode?> "
48 "fixed_latency_range=<disable latency range changes on underrun?> "
49 "ignore_dB=<ignore dB information from the device?> "
50 "deferred_volume=<syncronize sw and hw volume changes in IO-thread?>");
54 pa_bool_t need_verify;
58 pa_ratelimit ratelimit;
65 pa_bool_t use_tsched:1;
66 pa_bool_t fixed_latency_range:1;
67 pa_bool_t ignore_dB:1;
68 pa_bool_t deferred_volume:1;
71 struct udev_monitor *monitor;
75 pa_io_event *inotify_io;
78 static const char* const valid_modargs[] = {
80 "fixed_latency_range",
86 static int setup_inotify(struct userdata *u);
88 static void device_free(struct device *d) {
92 pa_xfree(d->card_name);
97 static const char *path_get_card_id(const char *path) {
103 if (!(e = strrchr(path, '/')))
106 if (!pa_startswith(e, "/card"))
112 static char *card_get_sysattr(const char *card_idx, const char *name) {
114 struct udev_device *card = NULL;
121 if (!(udev = udev_new())) {
122 pa_log_error("Failed to allocate udev context.");
126 t = pa_sprintf_malloc("/sys/class/sound/card%s", card_idx);
127 card = udev_device_new_from_syspath(udev, t);
131 pa_log_error("Failed to get card object.");
135 if ((v = udev_device_get_sysattr_value(card, name)) && *v)
141 udev_device_unref(card);
149 static pa_bool_t pcm_is_modem(const char *card_idx, const char *pcm) {
150 char *sysfs_path, *pcm_class;
156 /* Check /sys/class/sound/card.../pcmC...../pcm_class. An HDA
157 * modem can be used simultaneously with generic
158 * playback/record. */
160 sysfs_path = pa_sprintf_malloc("pcmC%sD%s/pcm_class", card_idx, pcm);
161 pcm_class = card_get_sysattr(card_idx, sysfs_path);
162 is_modem = pcm_class && pa_streq(pcm_class, "modem");
164 pa_xfree(sysfs_path);
169 static pa_bool_t is_card_busy(const char *id) {
170 char *card_path = NULL, *pcm_path = NULL, *sub_status = NULL;
171 DIR *card_dir = NULL, *pcm_dir = NULL;
172 FILE *status_file = NULL;
174 struct dirent *space = NULL, *de;
175 pa_bool_t busy = FALSE;
180 /* This simply uses /proc/asound/card.../pcm.../sub.../status to
181 * check whether there is still a process using this audio device. */
183 card_path = pa_sprintf_malloc("/proc/asound/card%s", id);
185 if (!(card_dir = opendir(card_path))) {
186 pa_log_warn("Failed to open %s: %s", card_path, pa_cstrerror(errno));
190 len = offsetof(struct dirent, d_name) + fpathconf(dirfd(card_dir), _PC_NAME_MAX) + 1;
191 space = pa_xmalloc(len);
196 if ((r = readdir_r(card_dir, space, &de)) != 0) {
197 pa_log_warn("readdir_r() failed: %s", pa_cstrerror(r));
204 if (!pa_startswith(de->d_name, "pcm"))
207 if (pcm_is_modem(id, de->d_name + 3))
211 pcm_path = pa_sprintf_malloc("%s/%s", card_path, de->d_name);
216 if (!(pcm_dir = opendir(pcm_path))) {
217 pa_log_warn("Failed to open %s: %s", pcm_path, pa_cstrerror(errno));
224 if ((r = readdir_r(pcm_dir, space, &de)) != 0) {
225 pa_log_warn("readdir_r() failed: %s", pa_cstrerror(r));
232 if (!pa_startswith(de->d_name, "sub"))
235 pa_xfree(sub_status);
236 sub_status = pa_sprintf_malloc("%s/%s/status", pcm_path, de->d_name);
241 if (!(status_file = pa_fopen_cloexec(sub_status, "r"))) {
242 pa_log_warn("Failed to open %s: %s", sub_status, pa_cstrerror(errno));
246 if (!(fgets(line, sizeof(line)-1, status_file))) {
247 pa_log_warn("Failed to read from %s: %s", sub_status, pa_cstrerror(errno));
251 if (!pa_streq(line, "closed\n")) {
262 pa_xfree(sub_status);
277 static void verify_access(struct userdata *u, struct device *d) {
280 pa_bool_t accessible;
285 cd = pa_sprintf_malloc("/dev/snd/controlC%s", path_get_card_id(d->path));
286 accessible = access(cd, R_OK|W_OK) >= 0;
287 pa_log_debug("%s is accessible: %s", cd, pa_yes_no(accessible));
291 if (d->module == PA_INVALID_INDEX) {
293 /* If we are not loaded, try to load */
299 /* Check if any of the PCM devices that belong to this
300 * card are currently busy. If they are, don't try to load
301 * right now, to make sure the probing phase can
302 * successfully complete. When the current user of the
303 * device closes it we will get another notification via
304 * inotify and can then recheck. */
306 busy = is_card_busy(path_get_card_id(d->path));
307 pa_log_debug("%s is busy: %s", d->path, pa_yes_no(busy));
311 /* So, why do we rate limit here? It's certainly ugly,
312 * but there seems to be no other way. Problem is
313 * this: if we are unable to configure/probe an audio
314 * device after opening it we will close it again and
315 * the module initialization will fail. This will then
316 * cause an inotify event on the device node which
317 * will be forwarded to us. We then try to reopen the
318 * audio device again, practically entering a busy
321 * A clean fix would be if we would be able to ignore
322 * our own inotify close events. However, inotify
323 * lacks such functionality. Also, during probing of
324 * the device we cannot really distinguish between
325 * other processes causing EBUSY or ourselves, which
326 * means we have no way to figure out if the probing
327 * during opening was canceled by a "try again"
328 * failure or a "fatal" failure. */
330 if (pa_ratelimit_test(&d->ratelimit, PA_LOG_DEBUG)) {
331 pa_log_debug("Loading module-alsa-card with arguments '%s'", d->args);
332 m = pa_module_load(u->core, "module-alsa-card", d->args);
335 d->module = m->index;
336 pa_log_info("Card %s (%s) module loaded.", d->path, d->card_name);
338 pa_log_info("Card %s (%s) failed to load module.", d->path, d->card_name);
340 pa_log_warn("Tried to configure %s (%s) more often than %u times in %llus",
344 (long long unsigned) (d->ratelimit.interval / PA_USEC_PER_SEC));
350 /* If we are already loaded update suspend status with
351 * accessible boolean */
353 if ((card = pa_namereg_get(u->core, d->card_name, PA_NAMEREG_CARD)))
354 pa_card_suspend(card, !accessible, PA_SUSPEND_SESSION);
358 static void card_changed(struct userdata *u, struct udev_device *dev) {
367 /* Maybe /dev/snd is now available? */
370 path = udev_device_get_devpath(dev);
372 if ((d = pa_hashmap_get(u->devices, path))) {
377 d = pa_xnew0(struct device, 1);
378 d->path = pa_xstrdup(path);
379 d->module = PA_INVALID_INDEX;
380 PA_INIT_RATELIMIT(d->ratelimit, 10*PA_USEC_PER_SEC, 5);
382 if (!(t = udev_device_get_property_value(dev, "PULSE_NAME")))
383 if (!(t = udev_device_get_property_value(dev, "ID_ID")))
384 if (!(t = udev_device_get_property_value(dev, "ID_PATH")))
385 t = path_get_card_id(path);
387 n = pa_namereg_make_valid_name(t);
388 d->card_name = pa_sprintf_malloc("alsa_card.%s", n);
389 d->args = pa_sprintf_malloc("device_id=\"%s\" "
392 "namereg_fail=false "
394 "fixed_latency_range=%s "
396 "deferred_volume=%s "
397 "card_properties=\"module-udev-detect.discovered=1\"",
398 path_get_card_id(path),
401 pa_yes_no(u->use_tsched),
402 pa_yes_no(u->fixed_latency_range),
403 pa_yes_no(u->ignore_dB),
404 pa_yes_no(u->deferred_volume));
407 pa_hashmap_put(u->devices, d->path, d);
412 static void remove_card(struct userdata *u, struct udev_device *dev) {
418 if (!(d = pa_hashmap_remove(u->devices, udev_device_get_devpath(dev))))
421 pa_log_info("Card %s removed.", d->path);
423 if (d->module != PA_INVALID_INDEX)
424 pa_module_unload_request_by_index(u->core, d->module, TRUE);
429 static void process_device(struct userdata *u, struct udev_device *dev) {
430 const char *action, *ff;
435 if (udev_device_get_property_value(dev, "PULSE_IGNORE")) {
436 pa_log_debug("Ignoring %s, because marked so.", udev_device_get_devpath(dev));
440 if ((ff = udev_device_get_property_value(dev, "SOUND_CLASS")) &&
441 pa_streq(ff, "modem")) {
442 pa_log_debug("Ignoring %s, because it is a modem.", udev_device_get_devpath(dev));
446 action = udev_device_get_action(dev);
448 if (action && pa_streq(action, "remove"))
450 else if ((!action || pa_streq(action, "change")) && udev_device_get_property_value(dev, "SOUND_INITIALIZED"))
451 card_changed(u, dev);
453 /* For an explanation why we don't look for 'add' events here
454 * have a look into /lib/udev/rules.d/78-sound-card.rules! */
457 static void process_path(struct userdata *u, const char *path) {
458 struct udev_device *dev;
460 if (!path_get_card_id(path))
463 if (!(dev = udev_device_new_from_syspath(u->udev, path))) {
464 pa_log("Failed to get udev device object from udev.");
468 process_device(u, dev);
469 udev_device_unref(dev);
472 static void monitor_cb(
476 pa_io_event_flags_t events,
479 struct userdata *u = userdata;
480 struct udev_device *dev;
484 if (!(dev = udev_monitor_receive_device(u->monitor))) {
485 pa_log("Failed to get udev device object from monitor.");
489 if (!path_get_card_id(udev_device_get_devpath(dev))) {
490 udev_device_unref(dev);
494 process_device(u, dev);
495 udev_device_unref(dev);
499 a->io_free(u->udev_io);
503 static pa_bool_t pcm_node_belongs_to_device(
510 cd = pa_sprintf_malloc("pcmC%sD", path_get_card_id(d->path));
511 b = pa_startswith(node, cd);
517 static pa_bool_t control_node_belongs_to_device(
524 cd = pa_sprintf_malloc("controlC%s", path_get_card_id(d->path));
525 b = pa_streq(node, cd);
531 static void inotify_cb(
535 pa_io_event_flags_t events,
539 struct inotify_event e;
542 struct userdata *u = userdata;
544 pa_bool_t deleted = FALSE;
550 struct inotify_event *event;
553 if ((r = pa_read(fd, &buf, sizeof(buf), &type)) <= 0) {
555 if (r < 0 && errno == EAGAIN)
558 pa_log("read() from inotify failed: %s", r < 0 ? pa_cstrerror(errno) : "EOF");
566 if ((size_t) r < sizeof(struct inotify_event)) {
567 pa_log("read() too short.");
571 len = sizeof(struct inotify_event) + event->len;
573 if ((size_t) r < len) {
574 pa_log("Payload missing.");
578 /* From udev we get the guarantee that the control
579 * device's ACL is changed last. To avoid races when ACLs
580 * are changed we hence watch only the control device */
581 if (((event->mask & IN_ATTRIB) && pa_startswith(event->name, "controlC")))
582 PA_HASHMAP_FOREACH(d, u->devices, state)
583 if (control_node_belongs_to_device(d, event->name))
584 d->need_verify = TRUE;
586 /* ALSA doesn't really give us any guarantee on the closing
587 * order, so let's simply hope */
588 if (((event->mask & IN_CLOSE_WRITE) && pa_startswith(event->name, "pcmC")))
589 PA_HASHMAP_FOREACH(d, u->devices, state)
590 if (pcm_node_belongs_to_device(d, event->name))
591 d->need_verify = TRUE;
593 /* /dev/snd/ might have been removed */
594 if ((event->mask & (IN_DELETE_SELF|IN_MOVE_SELF)))
597 event = (struct inotify_event*) ((uint8_t*) event + len);
602 PA_HASHMAP_FOREACH(d, u->devices, state)
603 if (d->need_verify) {
604 d->need_verify = FALSE;
613 a->io_free(u->inotify_io);
614 u->inotify_io = NULL;
617 if (u->inotify_fd >= 0) {
618 pa_close(u->inotify_fd);
623 static int setup_inotify(struct userdata *u) {
626 if (u->inotify_fd >= 0)
629 if ((u->inotify_fd = inotify_init1(IN_CLOEXEC|IN_NONBLOCK)) < 0) {
630 pa_log("inotify_init1() failed: %s", pa_cstrerror(errno));
634 r = inotify_add_watch(u->inotify_fd, "/dev/snd", IN_ATTRIB|IN_CLOSE_WRITE|IN_DELETE_SELF|IN_MOVE_SELF);
637 int saved_errno = errno;
639 pa_close(u->inotify_fd);
642 if (saved_errno == ENOENT) {
643 pa_log_debug("/dev/snd/ is apparently not existing yet, retrying to create inotify watch later.");
647 if (saved_errno == ENOSPC) {
648 pa_log("You apparently ran out of inotify watches, probably because Tracker/Beagle took them all away. "
649 "I wished people would do their homework first and fix inotify before using it for watching whole "
650 "directory trees which is something the current inotify is certainly not useful for. "
651 "Please make sure to drop the Tracker/Beagle guys a line complaining about their broken use of inotify.");
655 pa_log("inotify_add_watch() failed: %s", pa_cstrerror(saved_errno));
659 pa_assert_se(u->inotify_io = u->core->mainloop->io_new(u->core->mainloop, u->inotify_fd, PA_IO_EVENT_INPUT, inotify_cb, u));
664 int pa__init(pa_module *m) {
665 struct userdata *u = NULL;
667 struct udev_enumerate *enumerate = NULL;
668 struct udev_list_entry *item = NULL, *first = NULL;
670 pa_bool_t use_tsched = TRUE, fixed_latency_range = FALSE, ignore_dB = FALSE, deferred_volume = m->core->deferred_volume;
675 if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
676 pa_log("Failed to parse module arguments");
680 m->userdata = u = pa_xnew0(struct userdata, 1);
682 u->devices = pa_hashmap_new(pa_idxset_string_hash_func, pa_idxset_string_compare_func);
685 if (pa_modargs_get_value_boolean(ma, "tsched", &use_tsched) < 0) {
686 pa_log("Failed to parse tsched= argument.");
689 u->use_tsched = use_tsched;
691 if (pa_modargs_get_value_boolean(ma, "fixed_latency_range", &fixed_latency_range) < 0) {
692 pa_log("Failed to parse fixed_latency_range= argument.");
695 u->fixed_latency_range = fixed_latency_range;
697 if (pa_modargs_get_value_boolean(ma, "ignore_dB", &ignore_dB) < 0) {
698 pa_log("Failed to parse ignore_dB= argument.");
701 u->ignore_dB = ignore_dB;
703 if (pa_modargs_get_value_boolean(ma, "deferred_volume", &deferred_volume) < 0) {
704 pa_log("Failed to parse deferred_volume= argument.");
707 u->deferred_volume = deferred_volume;
709 if (!(u->udev = udev_new())) {
710 pa_log("Failed to initialize udev library.");
714 if (setup_inotify(u) < 0)
717 if (!(u->monitor = udev_monitor_new_from_netlink(u->udev, "udev"))) {
718 pa_log("Failed to initialize monitor.");
722 if (udev_monitor_filter_add_match_subsystem_devtype(u->monitor, "sound", NULL) < 0) {
723 pa_log("Failed to subscribe to sound devices.");
728 if (udev_monitor_enable_receiving(u->monitor) < 0) {
729 pa_log("Failed to enable monitor: %s", pa_cstrerror(errno));
731 pa_log_info("Most likely your kernel is simply too old and "
732 "allows only privileged processes to listen to device events. "
733 "Please upgrade your kernel to at least 2.6.30.");
737 if ((fd = udev_monitor_get_fd(u->monitor)) < 0) {
738 pa_log("Failed to get udev monitor fd.");
742 pa_assert_se(u->udev_io = u->core->mainloop->io_new(u->core->mainloop, fd, PA_IO_EVENT_INPUT, monitor_cb, u));
744 if (!(enumerate = udev_enumerate_new(u->udev))) {
745 pa_log("Failed to initialize udev enumerator.");
749 if (udev_enumerate_add_match_subsystem(enumerate, "sound") < 0) {
750 pa_log("Failed to match to subsystem.");
754 if (udev_enumerate_scan_devices(enumerate) < 0) {
755 pa_log("Failed to scan for devices.");
759 first = udev_enumerate_get_list_entry(enumerate);
760 udev_list_entry_foreach(item, first)
761 process_path(u, udev_list_entry_get_name(item));
763 udev_enumerate_unref(enumerate);
765 pa_log_info("Found %u cards.", pa_hashmap_size(u->devices));
774 udev_enumerate_unref(enumerate);
784 void pa__done(pa_module *m) {
789 if (!(u = m->userdata))
793 m->core->mainloop->io_free(u->udev_io);
796 udev_monitor_unref(u->monitor);
802 m->core->mainloop->io_free(u->inotify_io);
804 if (u->inotify_fd >= 0)
805 pa_close(u->inotify_fd);
810 while ((d = pa_hashmap_steal_first(u->devices)))
813 pa_hashmap_free(u->devices, NULL, NULL);