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>
39 #include <pulsecore/strbuf.h>
41 #include "module-udev-detect-symdef.h"
43 PA_MODULE_AUTHOR("Lennart Poettering");
44 PA_MODULE_DESCRIPTION("Detect available audio hardware and load matching drivers");
45 PA_MODULE_VERSION(PACKAGE_VERSION
);
46 PA_MODULE_LOAD_ONCE(true);
48 "tsched=<enable system timer based scheduling mode?> "
49 "tsched_buffer_size=<buffer size when using timer based scheduling> "
50 "fixed_latency_range=<disable latency range changes on underrun?> "
51 "ignore_dB=<ignore dB information from the device?> "
52 "deferred_volume=<syncronize sw and hw volume changes in IO-thread?> "
53 "use_ucm=<use ALSA UCM for card configuration?>");
61 pa_ratelimit ratelimit
;
69 bool tsched_buffer_size_valid
:1;
70 bool fixed_latency_range
:1;
72 bool deferred_volume
:1;
75 uint32_t tsched_buffer_size
;
78 struct udev_monitor
*monitor
;
82 pa_io_event
*inotify_io
;
85 static const char* const valid_modargs
[] = {
88 "fixed_latency_range",
95 static int setup_inotify(struct userdata
*u
);
97 static void device_free(struct device
*d
) {
101 pa_xfree(d
->card_name
);
106 static const char *path_get_card_id(const char *path
) {
112 if (!(e
= strrchr(path
, '/')))
115 if (!pa_startswith(e
, "/card"))
121 static char *card_get_sysattr(const char *card_idx
, const char *name
) {
123 struct udev_device
*card
= NULL
;
130 if (!(udev
= udev_new())) {
131 pa_log_error("Failed to allocate udev context.");
135 t
= pa_sprintf_malloc("/sys/class/sound/card%s", card_idx
);
136 card
= udev_device_new_from_syspath(udev
, t
);
140 pa_log_error("Failed to get card object.");
144 if ((v
= udev_device_get_sysattr_value(card
, name
)) && *v
)
150 udev_device_unref(card
);
158 static bool pcm_is_modem(const char *card_idx
, const char *pcm
) {
159 char *sysfs_path
, *pcm_class
;
165 /* Check /sys/class/sound/card.../pcmC...../pcm_class. An HDA
166 * modem can be used simultaneously with generic
167 * playback/record. */
169 sysfs_path
= pa_sprintf_malloc("pcmC%sD%s/pcm_class", card_idx
, pcm
);
170 pcm_class
= card_get_sysattr(card_idx
, sysfs_path
);
171 is_modem
= pcm_class
&& pa_streq(pcm_class
, "modem");
173 pa_xfree(sysfs_path
);
178 static bool is_card_busy(const char *id
) {
179 char *card_path
= NULL
, *pcm_path
= NULL
, *sub_status
= NULL
;
180 DIR *card_dir
= NULL
, *pcm_dir
= NULL
;
181 FILE *status_file
= NULL
;
183 struct dirent
*space
= NULL
, *de
;
189 /* This simply uses /proc/asound/card.../pcm.../sub.../status to
190 * check whether there is still a process using this audio device. */
192 card_path
= pa_sprintf_malloc("/proc/asound/card%s", id
);
194 if (!(card_dir
= opendir(card_path
))) {
195 pa_log_warn("Failed to open %s: %s", card_path
, pa_cstrerror(errno
));
199 len
= offsetof(struct dirent
, d_name
) + fpathconf(dirfd(card_dir
), _PC_NAME_MAX
) + 1;
200 space
= pa_xmalloc(len
);
205 if ((r
= readdir_r(card_dir
, space
, &de
)) != 0) {
206 pa_log_warn("readdir_r() failed: %s", pa_cstrerror(r
));
213 if (!pa_startswith(de
->d_name
, "pcm"))
216 if (pcm_is_modem(id
, de
->d_name
+ 3))
220 pcm_path
= pa_sprintf_malloc("%s/%s", card_path
, de
->d_name
);
225 if (!(pcm_dir
= opendir(pcm_path
))) {
226 pa_log_warn("Failed to open %s: %s", pcm_path
, pa_cstrerror(errno
));
233 if ((r
= readdir_r(pcm_dir
, space
, &de
)) != 0) {
234 pa_log_warn("readdir_r() failed: %s", pa_cstrerror(r
));
241 if (!pa_startswith(de
->d_name
, "sub"))
244 pa_xfree(sub_status
);
245 sub_status
= pa_sprintf_malloc("%s/%s/status", pcm_path
, de
->d_name
);
250 if (!(status_file
= pa_fopen_cloexec(sub_status
, "r"))) {
251 pa_log_warn("Failed to open %s: %s", sub_status
, pa_cstrerror(errno
));
255 if (!(fgets(line
, sizeof(line
)-1, status_file
))) {
256 pa_log_warn("Failed to read from %s: %s", sub_status
, pa_cstrerror(errno
));
260 if (!pa_streq(line
, "closed\n")) {
271 pa_xfree(sub_status
);
286 static void verify_access(struct userdata
*u
, struct device
*d
) {
294 cd
= pa_sprintf_malloc("/dev/snd/controlC%s", path_get_card_id(d
->path
));
295 accessible
= access(cd
, R_OK
|W_OK
) >= 0;
296 pa_log_debug("%s is accessible: %s", cd
, pa_yes_no(accessible
));
300 if (d
->module
== PA_INVALID_INDEX
) {
302 /* If we are not loaded, try to load */
308 /* Check if any of the PCM devices that belong to this
309 * card are currently busy. If they are, don't try to load
310 * right now, to make sure the probing phase can
311 * successfully complete. When the current user of the
312 * device closes it we will get another notification via
313 * inotify and can then recheck. */
315 busy
= is_card_busy(path_get_card_id(d
->path
));
316 pa_log_debug("%s is busy: %s", d
->path
, pa_yes_no(busy
));
320 /* So, why do we rate limit here? It's certainly ugly,
321 * but there seems to be no other way. Problem is
322 * this: if we are unable to configure/probe an audio
323 * device after opening it we will close it again and
324 * the module initialization will fail. This will then
325 * cause an inotify event on the device node which
326 * will be forwarded to us. We then try to reopen the
327 * audio device again, practically entering a busy
330 * A clean fix would be if we would be able to ignore
331 * our own inotify close events. However, inotify
332 * lacks such functionality. Also, during probing of
333 * the device we cannot really distinguish between
334 * other processes causing EBUSY or ourselves, which
335 * means we have no way to figure out if the probing
336 * during opening was canceled by a "try again"
337 * failure or a "fatal" failure. */
339 if (pa_ratelimit_test(&d
->ratelimit
, PA_LOG_DEBUG
)) {
340 pa_log_debug("Loading module-alsa-card with arguments '%s'", d
->args
);
341 m
= pa_module_load(u
->core
, "module-alsa-card", d
->args
);
344 d
->module
= m
->index
;
345 pa_log_info("Card %s (%s) module loaded.", d
->path
, d
->card_name
);
347 pa_log_info("Card %s (%s) failed to load module.", d
->path
, d
->card_name
);
349 pa_log_warn("Tried to configure %s (%s) more often than %u times in %llus",
353 (long long unsigned) (d
->ratelimit
.interval
/ PA_USEC_PER_SEC
));
359 /* If we are already loaded update suspend status with
360 * accessible boolean */
362 if ((card
= pa_namereg_get(u
->core
, d
->card_name
, PA_NAMEREG_CARD
))) {
363 pa_log_debug("%s all sinks and sources of card %s.", accessible
? "Resuming" : "Suspending", d
->card_name
);
364 pa_card_suspend(card
, !accessible
, PA_SUSPEND_SESSION
);
369 static void card_changed(struct userdata
*u
, struct udev_device
*dev
) {
379 /* Maybe /dev/snd is now available? */
382 path
= udev_device_get_devpath(dev
);
384 if ((d
= pa_hashmap_get(u
->devices
, path
))) {
389 d
= pa_xnew0(struct device
, 1);
390 d
->path
= pa_xstrdup(path
);
391 d
->module
= PA_INVALID_INDEX
;
392 PA_INIT_RATELIMIT(d
->ratelimit
, 10*PA_USEC_PER_SEC
, 5);
394 if (!(t
= udev_device_get_property_value(dev
, "PULSE_NAME")))
395 if (!(t
= udev_device_get_property_value(dev
, "ID_ID")))
396 if (!(t
= udev_device_get_property_value(dev
, "ID_PATH")))
397 t
= path_get_card_id(path
);
399 n
= pa_namereg_make_valid_name(t
);
400 d
->card_name
= pa_sprintf_malloc("alsa_card.%s", n
);
401 args_buf
= pa_strbuf_new();
402 pa_strbuf_printf(args_buf
,
406 "namereg_fail=false "
408 "fixed_latency_range=%s "
410 "deferred_volume=%s "
412 "card_properties=\"module-udev-detect.discovered=1\"",
413 path_get_card_id(path
),
416 pa_yes_no(u
->use_tsched
),
417 pa_yes_no(u
->fixed_latency_range
),
418 pa_yes_no(u
->ignore_dB
),
419 pa_yes_no(u
->deferred_volume
),
420 pa_yes_no(u
->use_ucm
));
423 if (u
->tsched_buffer_size_valid
)
424 pa_strbuf_printf(args_buf
, " tsched_buffer_size=%" PRIu32
, u
->tsched_buffer_size
);
426 d
->args
= pa_strbuf_tostring_free(args_buf
);
428 pa_hashmap_put(u
->devices
, d
->path
, d
);
433 static void remove_card(struct userdata
*u
, struct udev_device
*dev
) {
439 if (!(d
= pa_hashmap_remove(u
->devices
, udev_device_get_devpath(dev
))))
442 pa_log_info("Card %s removed.", d
->path
);
444 if (d
->module
!= PA_INVALID_INDEX
)
445 pa_module_unload_request_by_index(u
->core
, d
->module
, true);
450 static void process_device(struct userdata
*u
, struct udev_device
*dev
) {
451 const char *action
, *ff
;
456 if (udev_device_get_property_value(dev
, "PULSE_IGNORE")) {
457 pa_log_debug("Ignoring %s, because marked so.", udev_device_get_devpath(dev
));
461 if ((ff
= udev_device_get_property_value(dev
, "SOUND_CLASS")) &&
462 pa_streq(ff
, "modem")) {
463 pa_log_debug("Ignoring %s, because it is a modem.", udev_device_get_devpath(dev
));
467 action
= udev_device_get_action(dev
);
469 if (action
&& pa_streq(action
, "remove"))
471 else if ((!action
|| pa_streq(action
, "change")) && udev_device_get_property_value(dev
, "SOUND_INITIALIZED"))
472 card_changed(u
, dev
);
474 /* For an explanation why we don't look for 'add' events here
475 * have a look into /lib/udev/rules.d/78-sound-card.rules! */
478 static void process_path(struct userdata
*u
, const char *path
) {
479 struct udev_device
*dev
;
481 if (!path_get_card_id(path
))
484 if (!(dev
= udev_device_new_from_syspath(u
->udev
, path
))) {
485 pa_log("Failed to get udev device object from udev.");
489 process_device(u
, dev
);
490 udev_device_unref(dev
);
493 static void monitor_cb(
497 pa_io_event_flags_t events
,
500 struct userdata
*u
= userdata
;
501 struct udev_device
*dev
;
505 if (!(dev
= udev_monitor_receive_device(u
->monitor
))) {
506 pa_log("Failed to get udev device object from monitor.");
510 if (!path_get_card_id(udev_device_get_devpath(dev
))) {
511 udev_device_unref(dev
);
515 process_device(u
, dev
);
516 udev_device_unref(dev
);
520 a
->io_free(u
->udev_io
);
524 static bool pcm_node_belongs_to_device(
531 cd
= pa_sprintf_malloc("pcmC%sD", path_get_card_id(d
->path
));
532 b
= pa_startswith(node
, cd
);
538 static bool control_node_belongs_to_device(
545 cd
= pa_sprintf_malloc("controlC%s", path_get_card_id(d
->path
));
546 b
= pa_streq(node
, cd
);
552 static void inotify_cb(
556 pa_io_event_flags_t events
,
560 struct inotify_event e
;
563 struct userdata
*u
= userdata
;
565 bool deleted
= false;
571 struct inotify_event
*event
;
574 if ((r
= pa_read(fd
, &buf
, sizeof(buf
), &type
)) <= 0) {
576 if (r
< 0 && errno
== EAGAIN
)
579 pa_log("read() from inotify failed: %s", r
< 0 ? pa_cstrerror(errno
) : "EOF");
587 if ((size_t) r
< sizeof(struct inotify_event
)) {
588 pa_log("read() too short.");
592 len
= sizeof(struct inotify_event
) + event
->len
;
594 if ((size_t) r
< len
) {
595 pa_log("Payload missing.");
599 /* From udev we get the guarantee that the control
600 * device's ACL is changed last. To avoid races when ACLs
601 * are changed we hence watch only the control device */
602 if (((event
->mask
& IN_ATTRIB
) && pa_startswith(event
->name
, "controlC")))
603 PA_HASHMAP_FOREACH(d
, u
->devices
, state
)
604 if (control_node_belongs_to_device(d
, event
->name
))
605 d
->need_verify
= true;
607 /* ALSA doesn't really give us any guarantee on the closing
608 * order, so let's simply hope */
609 if (((event
->mask
& IN_CLOSE_WRITE
) && pa_startswith(event
->name
, "pcmC")))
610 PA_HASHMAP_FOREACH(d
, u
->devices
, state
)
611 if (pcm_node_belongs_to_device(d
, event
->name
))
612 d
->need_verify
= true;
614 /* /dev/snd/ might have been removed */
615 if ((event
->mask
& (IN_DELETE_SELF
|IN_MOVE_SELF
)))
618 event
= (struct inotify_event
*) ((uint8_t*) event
+ len
);
623 PA_HASHMAP_FOREACH(d
, u
->devices
, state
)
624 if (d
->need_verify
) {
625 d
->need_verify
= false;
634 a
->io_free(u
->inotify_io
);
635 u
->inotify_io
= NULL
;
638 if (u
->inotify_fd
>= 0) {
639 pa_close(u
->inotify_fd
);
644 static int setup_inotify(struct userdata
*u
) {
647 if (u
->inotify_fd
>= 0)
650 if ((u
->inotify_fd
= inotify_init1(IN_CLOEXEC
|IN_NONBLOCK
)) < 0) {
651 pa_log("inotify_init1() failed: %s", pa_cstrerror(errno
));
655 r
= inotify_add_watch(u
->inotify_fd
, "/dev/snd", IN_ATTRIB
|IN_CLOSE_WRITE
|IN_DELETE_SELF
|IN_MOVE_SELF
);
658 int saved_errno
= errno
;
660 pa_close(u
->inotify_fd
);
663 if (saved_errno
== ENOENT
) {
664 pa_log_debug("/dev/snd/ is apparently not existing yet, retrying to create inotify watch later.");
668 if (saved_errno
== ENOSPC
) {
669 pa_log("You apparently ran out of inotify watches, probably because Tracker/Beagle took them all away. "
670 "I wished people would do their homework first and fix inotify before using it for watching whole "
671 "directory trees which is something the current inotify is certainly not useful for. "
672 "Please make sure to drop the Tracker/Beagle guys a line complaining about their broken use of inotify.");
676 pa_log("inotify_add_watch() failed: %s", pa_cstrerror(saved_errno
));
680 pa_assert_se(u
->inotify_io
= u
->core
->mainloop
->io_new(u
->core
->mainloop
, u
->inotify_fd
, PA_IO_EVENT_INPUT
, inotify_cb
, u
));
685 int pa__init(pa_module
*m
) {
686 struct userdata
*u
= NULL
;
688 struct udev_enumerate
*enumerate
= NULL
;
689 struct udev_list_entry
*item
= NULL
, *first
= NULL
;
691 bool use_tsched
= true, fixed_latency_range
= false, ignore_dB
= false, deferred_volume
= m
->core
->deferred_volume
;
696 if (!(ma
= pa_modargs_new(m
->argument
, valid_modargs
))) {
697 pa_log("Failed to parse module arguments");
701 m
->userdata
= u
= pa_xnew0(struct userdata
, 1);
703 u
->devices
= pa_hashmap_new_full(pa_idxset_string_hash_func
, pa_idxset_string_compare_func
, NULL
, (pa_free_cb_t
) device_free
);
706 if (pa_modargs_get_value_boolean(ma
, "tsched", &use_tsched
) < 0) {
707 pa_log("Failed to parse tsched= argument.");
710 u
->use_tsched
= use_tsched
;
712 if (pa_modargs_get_value(ma
, "tsched_buffer_size", NULL
)) {
713 if (pa_modargs_get_value_u32(ma
, "tsched_buffer_size", &u
->tsched_buffer_size
) < 0) {
714 pa_log("Failed to parse tsched_buffer_size= argument.");
718 u
->tsched_buffer_size_valid
= true;
721 if (pa_modargs_get_value_boolean(ma
, "fixed_latency_range", &fixed_latency_range
) < 0) {
722 pa_log("Failed to parse fixed_latency_range= argument.");
725 u
->fixed_latency_range
= fixed_latency_range
;
727 if (pa_modargs_get_value_boolean(ma
, "ignore_dB", &ignore_dB
) < 0) {
728 pa_log("Failed to parse ignore_dB= argument.");
731 u
->ignore_dB
= ignore_dB
;
733 if (pa_modargs_get_value_boolean(ma
, "deferred_volume", &deferred_volume
) < 0) {
734 pa_log("Failed to parse deferred_volume= argument.");
737 u
->deferred_volume
= deferred_volume
;
739 if (pa_modargs_get_value_boolean(ma
, "use_ucm", &use_ucm
) < 0) {
740 pa_log("Failed to parse use_ucm= argument.");
743 u
->use_ucm
= use_ucm
;
745 if (!(u
->udev
= udev_new())) {
746 pa_log("Failed to initialize udev library.");
750 if (setup_inotify(u
) < 0)
753 if (!(u
->monitor
= udev_monitor_new_from_netlink(u
->udev
, "udev"))) {
754 pa_log("Failed to initialize monitor.");
758 if (udev_monitor_filter_add_match_subsystem_devtype(u
->monitor
, "sound", NULL
) < 0) {
759 pa_log("Failed to subscribe to sound devices.");
764 if (udev_monitor_enable_receiving(u
->monitor
) < 0) {
765 pa_log("Failed to enable monitor: %s", pa_cstrerror(errno
));
767 pa_log_info("Most likely your kernel is simply too old and "
768 "allows only privileged processes to listen to device events. "
769 "Please upgrade your kernel to at least 2.6.30.");
773 if ((fd
= udev_monitor_get_fd(u
->monitor
)) < 0) {
774 pa_log("Failed to get udev monitor fd.");
778 pa_assert_se(u
->udev_io
= u
->core
->mainloop
->io_new(u
->core
->mainloop
, fd
, PA_IO_EVENT_INPUT
, monitor_cb
, u
));
780 if (!(enumerate
= udev_enumerate_new(u
->udev
))) {
781 pa_log("Failed to initialize udev enumerator.");
785 if (udev_enumerate_add_match_subsystem(enumerate
, "sound") < 0) {
786 pa_log("Failed to match to subsystem.");
790 if (udev_enumerate_scan_devices(enumerate
) < 0) {
791 pa_log("Failed to scan for devices.");
795 first
= udev_enumerate_get_list_entry(enumerate
);
796 udev_list_entry_foreach(item
, first
)
797 process_path(u
, udev_list_entry_get_name(item
));
799 udev_enumerate_unref(enumerate
);
801 pa_log_info("Found %u cards.", pa_hashmap_size(u
->devices
));
810 udev_enumerate_unref(enumerate
);
820 void pa__done(pa_module
*m
) {
825 if (!(u
= m
->userdata
))
829 m
->core
->mainloop
->io_free(u
->udev_io
);
832 udev_monitor_unref(u
->monitor
);
838 m
->core
->mainloop
->io_free(u
->inotify_io
);
840 if (u
->inotify_fd
>= 0)
841 pa_close(u
->inotify_fd
);
844 pa_hashmap_free(u
->devices
);