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* ALSA: timer: Fix leftover link at closingTakashi Iwai2016-02-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | In ALSA timer core, the active timer instance is managed in active_list linked list. Each element is added / removed dynamically at timer start, stop and in timer interrupt. The problem is that snd_timer_interrupt() has a thinko and leaves the element in active_list when it's the last opened element. This eventually leads to list corruption or use-after-free error. This hasn't been revealed because we used to delete the list forcibly in snd_timer_stop() in the past. However, the recent fix avoids the double-stop behavior (in commit [f784beb75ce8: ALSA: timer: Fix link corruption due to double start or stop]), and this leak hits reality. This patch fixes the link management in snd_timer_interrupt(). Now it simply unlinks no matter which stream is. BugLink: http://lkml.kernel.org/r/CACT4Y+Yy2aukHP-EDp8-ziNqNNmb-NTf=jDWXMP7jB8HDa2vng@mail.gmail.com Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Sync timer deletion at closing the system timerTakashi Iwai2016-02-031-0/+10
| | | | | | | | | | | ALSA timer core framework has no sync point at stopping because it's called inside the spinlock. Thus we need a sync point at close for avoiding the stray timer task. This is simply done by implementing the close callback just calling del_timer_sync(). (It's harmless to call it unconditionally, as the core timer itself cares of the already deleted timer instance.) Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Fix link corruption due to double start or stopTakashi Iwai2016-02-011-2/+28
| | | | | | | | | | | | | | | | | | | Although ALSA timer code got hardening for races, it still causes use-after-free error. This is however rather a corrupted linked list, not actually the concurrent accesses. Namely, when timer start is triggered twice, list_add_tail() is called twice, too. This ends up with the link corruption and triggers KASAN error. The simplest fix would be replacing list_add_tail() with list_move_tail(), but fundamentally it's the problem that we don't check the double start/stop correctly. So, the right fix here is to add the proper checks to snd_timer_start() and snd_timer_stop() (and their variants). BugLink: http://lkml.kernel.org/r/CACT4Y+ZyPRoMQjmawbvmCEDrkBD2BQuH7R09=eOkf5ESK8kJAw@mail.gmail.com Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Introduce disconnect op to snd_timer_instanceTakashi Iwai2016-01-211-12/+11
| | | | | | | | | Instead of the previous ugly hack, introduce a new op, disconnect, to snd_timer_instance object for handling the wake up of pending tasks more cleanly. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=109431 Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Handle disconnection more safelyTakashi Iwai2016-01-211-0/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently ALSA timer device doesn't take the disconnection into account very well; it merely unlinks the timer device at disconnection callback but does nothing else. Because of this, when an application accessing the timer device is disconnected, it may release the resource before actually closed. In most cases, it results in a warning message indicating a leftover timer instance like: ALSA: timer xxxx is busy? But basically this is an open race. This patch tries to address it. The strategy is like other ALSA devices: namely, - Manage card's refcount at each open/close - Wake up the pending tasks at disconnection - Check the shutdown flag appropriately at each possible call Note that this patch has one ugly hack to handle the wakeup of pending tasks. It'd be cleaner to introduce a new disconnect op to snd_timer_instance ops. But since it would lead to internal ABI breakage and it eventually increase my own work when backporting to stable kernels, I took a different path to implement locally in timer.c. A cleanup patch will follow at next for 4.5 kernel. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=109431 Cc: <stable@vger.kernel.org> # v3.15+ Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Code cleanupTakashi Iwai2016-01-151-17/+11
| | | | | | | | | This is a minor code cleanup without any functional changes: - Kill keep_flag argument from _snd_timer_stop(), as all callers pass only it false. - Remove redundant NULL check in _snd_timer_stop(). Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Harden slave timer list handlingTakashi Iwai2016-01-151-4/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | A slave timer instance might be still accessible in a racy way while operating the master instance as it lacks of locking. Since the master operation is mostly protected with timer->lock, we should cope with it while changing the slave instance, too. Also, some linked lists (active_list and ack_list) of slave instances aren't unlinked immediately at stopping or closing, and this may lead to unexpected accesses. This patch tries to address these issues. It adds spin lock of timer->lock (either from master or slave, which is equivalent) in a few places. For avoiding a deadlock, we ensure that the global slave_active_lock is always locked at first before each timer lock. Also, ack and active_list of slave instances are properly unlinked at snd_timer_stop() and snd_timer_close(). Last but not least, remove the superfluous call of _snd_timer_stop() at removing slave links. This is a noop, and calling it may confuse readers wrt locking. Further cleanup will follow in a later patch. Actually we've got reports of use-after-free by syzkaller fuzzer, and this hopefully fixes these issues. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Fix race among timer ioctlsTakashi Iwai2016-01-141-13/+19
| | | | | | | | | | | | | | | | ALSA timer ioctls have an open race and this may lead to a use-after-free of timer instance object. A simplistic fix is to make each ioctl exclusive. We have already tread_sem for controlling the tread, and extend this as a global mutex to be applied to each ioctl. The downside is, of course, the worse concurrency. But these ioctls aren't to be parallel accessible, in anyway, so it should be fine to serialize there. Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Fix double unlink of active_listTakashi Iwai2016-01-131-1/+1
| | | | | | | | | | | | | | | ALSA timer instance object has a couple of linked lists and they are unlinked unconditionally at snd_timer_stop(). Meanwhile snd_timer_interrupt() unlinks it, but it calls list_del() which leaves the element list itself unchanged. This ends up with unlinking twice, and it was caught by syzkaller fuzzer. The fix is to use list_del_init() variant properly there, too. Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: replace CONFIG_PROC_FS with CONFIG_SND_PROC_FSJie Yang2015-05-271-2/+2
| | | | | | | | | | | | | We may disable proc fs only for sound part, to reduce ALSA memory footprint. So add CONFIG_SND_PROC_FS and replace the old CONFIG_PROC_FSs in alsa code. With sound proc fs disabled, we can save about 9KB memory size on X86_64 platform. Signed-off-by: Jie Yang <yang.jie@intel.com> Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: core: Drop superfluous error/debug messages after malloc failuresTakashi Iwai2015-03-101-3/+1
| | | | | | | | The kernel memory allocators already report the errors when the requested allocation fails, thus we don't need to warn it again in each caller side. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge branch 'topic/snd-device' into for-nextTakashi Iwai2015-02-031-11/+31
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| * ALSA: Simplify snd_device_register() variantsTakashi Iwai2015-02-021-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that all callers have been replaced with snd_device_register_for_dev(), let's drop the obsolete device registration code and concentrate only on the code handling struct device directly. That said, - remove the old snd_device_register(), - rename snd_device_register_for_dev() with snd_device_register(), - drop superfluous arguments from snd_device_register(), - change snd_unregister_device() to pass the device pointer directly Reviewed-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * ALSA: timer: Handle the device directlyTakashi Iwai2015-02-021-2/+11
| | | | | | | | | | | | | | | | This is a relatively straightforward change, using the struct device directly for managing the ALSA timer device. Reviewed-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de>
| * ALSA: timer: Propagate the error at initializationTakashi Iwai2015-02-021-10/+22
| | | | | | | | | | | | | | ... instead of just printing errors. Reviewed-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: timer: Use setup_timer() and mod_timer()Takashi Iwai2015-01-191-3/+1
|/ | | | | | No functional change, refactoring with the standard helpers. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: core: Use ktime_get_ts()Thomas Gleixner2014-06-121-2/+2
| | | | | | | | do_posix_clock_monotonic_gettime() is a leftover from the initial posix timer implementation which maps to ktime_get_ts(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Use standard printk helpersTakashi Iwai2014-02-141-7/+6
| | | | | | Use the standard pr_xxx() helpers instead of home-baked snd_print*(). Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: Replace with IS_ENABLED()Takashi Iwai2014-02-101-2/+2
| | | | | | | | | | | | Replace the lengthy #if defined(XXX) || defined(XXX_MODULE) with the new IS_ENABLED() macro. The patch still doesn't cover all ifdefs. For example, the dependency on CONFIG_GAMEPORT is still open-coded because this also has an extra dependency on MODULE. Similarly, an open-coded ifdef in pcm_oss.c and some sequencer-related stuff are left untouched. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* device.h: cleanup users outside of linux/include (C files)Paul Gortmaker2012-03-111-0/+1
| | | | | | | | | | | | | | For files that are actively using linux/device.h, make sure that they call it out. This will allow us to clean up some of the implicit uses of linux/device.h within include/* without introducing build regressions. Yes, this was created by "cheating" -- i.e. the headers were cleaned up, and then the fallout was found and fixed, and then the two commits were reordered. This ensures we don't introduce build regressions into the git history. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* sound: fix drivers needing module.h not moduleparam.hPaul Gortmaker2011-10-311-1/+1
| | | | | | | | | The implicit presence of module.h lured several users into incorrectly thinking that they only needed/used modparam.h but once we clean up the module.h presence, these will show up as build failures, so fix 'em now. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* ALSA: timer - Add NULL-check for invalid slave timerTakashi Iwai2011-08-081-0/+3
| | | | | | Just to be sure. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer - Fix Oops at closing slave timerTakashi Iwai2011-08-081-0/+2
| | | | | | | | | | | A slave-timer instance has no timer reference, and this results in NULL-dereference at stopping the timer, typically called at closing the device. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=40682 Cc: <stable@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: sound/core: merge list_del()/list_add_tail() to list_move_tail()Nicolas Kaiser2011-03-161-5/+3
| | | | | | | Merge list_del() + list_add_tail() to list_move_tail(). Signed-off-by: Nicolas Kaiser <nikai@nikai.net> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: support module on-demand loading for seq and timerKay Sievers2010-11-241-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_SND_DYNAMIC_MINORS is used, assign /dev/snd/seq and /dev/snd/timer the usual static minors, and export specific module aliases to generate udev module on-demand loading instructions: $ cat /lib/modules/2.6.33.4-smp/modules.devname # Device nodes to trigger on-demand module loading. microcode cpu/microcode c10:184 fuse fuse c10:229 ppp_generic ppp c108:0 tun net/tun c10:200 uinput uinput c10:223 dm_mod mapper/control c10:236 snd_timer snd/timer c116:33 snd_seq snd/seq c116:1 The last two lines instruct udev to create device nodes, even when the modules are not loaded at that time. As soon as userspace accesses any of these nodes, the in-kernel module-loader will load the module, and the device can be used. The header file minor calculation needed to be simplified to make __stringify() (supports only two indirections) in the MODULE_ALIAS macro work. This is part of systemd's effort to get rid of unconditional module load instructions and needless init scripts. Cc: Lennart Poettering <lennart@poettering.net> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: automatically load the high-resolution timerClemens Ladisch2010-11-221-2/+2
| | | | | | | | | | Increase the default timer limit so that snd-hrtimer.ko can be automatically loaded when needed, e.g., when used as the default sequencer timer. This replaces the check for the obsolete CONFIG_SND_HPET. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge branch 'topic/core-cleanup' into for-linusTakashi Iwai2010-05-201-0/+6
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| * ALSA: core - Define llseek fopsTakashi Iwai2010-04-131-0/+6
| | | | | | | | | | | | | | | | | | | | | | Set no_llseek to llseek file ops of each sound component (but for hwdep). This avoids the implicit BKL invocation via generic_file_llseek() used as default when fops.llseek is NULL. Also call nonseekable_open() at each open ops to ensure the file flags have no seek bit. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* | ALSA: take tu->qlock with irqs disabledDan Carpenter2010-05-051-2/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | We should disable irqs when we take the tu->qlock because it is used in the irq handler. The only place that doesn't is snd_timer_user_ccallback(). Most of the time snd_timer_user_ccallback() is called with interrupts disabled but the the first ti->ccallback() call in snd_timer_notify1() has interrupts enabled. This was caught by lockdep which generates the following message: > ================================= > [ INFO: inconsistent lock state ] > 2.6.34-rc5 #5 > --------------------------------- > inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. > dolphin/4003 [HC1[1]:SC0[0]:HE0:SE1] takes: > (&(&tu->qlock)->rlock){?.+...}, at: [<f84ec472>] snd_timer_user_tinterrupt+0x28/0x132 [snd_timer] > {HARDIRQ-ON-W} state was registered at: > [<c1048de9>] __lock_acquire+0x654/0x1482 > [<c1049c73>] lock_acquire+0x5c/0x73 > [<c125ac3e>] _raw_spin_lock+0x25/0x34 > [<f84ec370>] snd_timer_user_ccallback+0x55/0x95 [snd_timer] > [<f84ecc4b>] snd_timer_notify1+0x53/0xca [snd_timer] Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer - pass real event in snd_timer_notify1() to instance callbackJaroslav Kysela2010-03-031-1/+1
| | | | | | | Do not use hardcoded SNDRV_TIMER_EVENT_START value. Signed-off-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: sound/core: use memdup_user()Li Zefan2009-04-141-7/+4
| | | | | | | Remove open-coded memdup_user(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Rationalize fasync return valuesJonathan Corbet2009-03-161-5/+1
| | | | | | | | | | | | | | | | | | | | Most fasync implementations do something like: return fasync_helper(...); But fasync_helper() will return a positive value at times - a feature used in at least one place. Thus, a number of other drivers do: err = fasync_helper(...); if (err < 0) return err; return 0; In the interests of consistency and more concise code, it makes sense to map positive return values onto zero where ->fasync() is called. Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* ALSA: hda - Convert from takslet_hi_schedule() to tasklet_schedule()Takashi Iwai2008-12-181-1/+1
| | | | | | | | Replace all tasklet_hi_schedule() callers with the normal tasklet_schedule(). The former often causes troubles with RT-kernels, and has actually no merit. Signed-off-by: Takashi Iwai <tiwai@suse.de>
* saner FASYNC handling on file closeAl Viro2008-11-011-1/+0
| | | | | | | | | | | | | | As it is, all instances of ->release() for files that have ->fasync() need to remember to evict file from fasync lists; forgetting that creates a hole and we actually have a bunch that *does* forget. So let's keep our lives simple - let __fput() check FASYNC in file->f_flags and call ->fasync() there if it's been set. And lose that crap in ->release() instances - leaving it there is still valid, but we don't have to bother anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ALSA: fix a typo during snd_assert() removalTakashi Iwai2008-08-151-1/+1
| | | | | Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
* ALSA: Kill snd_assert() in sound/core/*Takashi Iwai2008-08-131-13/+20
| | | | | | | | Kill snd_assert() in sound/core/*, either removed or replaced with if () with snd_BUG_ON(). Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
* ALSA: remove CONFIG_KMOD from soundJohannes Berg2008-07-101-3/+3
| | | | | | | | | | A bunch of things in alsa depend on CONFIG_KMOD, use CONFIG_MODULES instead where the dependency is needed at all. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
* Dont touch fs_struct in driversJan Blunck2008-02-141-2/+0
| | | | | | | | | | | | | | | The sound drivers and the pnpbios core test for current->root != NULL. This test seems to be unnecessary since we always have rootfs mounted before initializing the drivers. Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Jaroslav Kysela <perex@suse.cz> Acked-by: Takashi Iwai <tiwai@suse.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [ALSA] Remove sound/driver.hTakashi Iwai2008-01-311-1/+0
| | | | | | | | | | | | This header file exists only for some hacks to adapt alsa-driver tree. It's useless for building in the kernel. Let's move a few lines in it to sound/core.h and remove it. With this patch, sound/driver.h isn't removed but has just a single compile warning to include it. This should be really killed in future. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
* [ALSA] Use posix clock monotonic for PCM and timer timestampsJaroslav Kysela2008-01-311-3/+13
| | | | | | | | | We need an accurate and continuous (monotonic) time sources to do accurate synchronization among more timing sources. This patch allows to enable monotonic timestamps for ALSA PCM devices and enables monotonic timestamps for ALSA timer devices. Signed-off-by: Jaroslav Kysela <perex@perex.cz>
* [ALSA] Changed Jaroslav Kysela's e-mail from perex@suse.cz to perex@perex.czJaroslav Kysela2007-10-161-2/+2
| | | | Signed-off-by: Jaroslav Kysela <perex@perex.cz>
* [ALSA] timer: check for incorrect device state in non-debug compiles, tooClemens Ladisch2007-07-201-9/+18
| | | | | | | | | Convert the snd_assert()s to simple if()s to prevent crashes when one of the timer instance ioctls is called before the file is bound to a timer device. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
* header cleaning: don't include smp_lock.h when not usedRandy Dunlap2007-05-081-1/+0
| | | | | | | | | | | | Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] mark struct file_operations const 9Arjan van de Ven2007-02-121-1/+1
| | | | | | | | | | | Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [ALSA] Remove useless reference to obsolete KERNELDRobert P. J. Day2007-02-091-3/+0
| | | | | | | | | Remove the final useless reference to the obsolete KERNELD feature. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
* [ALSA] alsa core: convert to list_for_each_entry*Johannes Berg2007-02-091-52/+25
| | | | | | | | | | | This patch converts most uses of list_for_each to list_for_each_entry all across alsa. In some place apparently an item can be on a list with different pointers so of course that isn't compatible with list_for_each, I therefore didn't touch those places. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
* [ALSA] system timer: remove unused snd_timer_system_private.timer fieldClemens Ladisch2006-09-231-1/+0
| | | | | | | Remove the snd_timer_system_private structure's timer field that was never used. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
* [ALSA] timer: fix timer reschedulingClemens Ladisch2006-09-231-1/+1
| | | | | | | | | When checking whether a hardware timer needs to be rescheduled, we have to compare against the previously scheduled interval and not against the actual interval between the last two interrupts. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
* [ALSA] system timer: clear correction value when timer stopsClemens Ladisch2006-09-231-0/+1
| | | | | | | Do not retain the old correction value when the timer was stopped. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
* [ALSA] system timer: accumulate correction for multiple lost ticksClemens Ladisch2006-09-231-1/+1
| | | | | | | | When multiple timer interrupts arrive too late, correct for all delays instead of ignoring the earlier ones. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
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