ALSA: compress: fix the return value for SNDRV_COMPRESS_VERSION
[linux-2.6.git] / sound / core / timer.c
index 0f6e672..6ddcf06 100644 (file)
@@ -1,6 +1,6 @@
 /*
  *  Timers abstract layer
- *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
+ *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  *
  *
  *   This program is free software; you can redistribute it and/or modify
  *
  */
 
-#include <sound/driver.h>
 #include <linux/delay.h>
 #include <linux/init.h>
-#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <linux/time.h>
 #include <linux/mutex.h>
-#include <linux/moduleparam.h>
+#include <linux/device.h>
+#include <linux/module.h>
 #include <linux/string.h>
 #include <sound/core.h>
 #include <sound/timer.h>
 #include <sound/minors.h>
 #include <sound/initval.h>
 #include <linux/kmod.h>
-#ifdef CONFIG_KERNELD
-#include <linux/kerneld.h>
-#endif
 
-#if defined(CONFIG_SND_HPET) || defined(CONFIG_SND_HPET_MODULE)
-#define DEFAULT_TIMER_LIMIT 3
+#if defined(CONFIG_SND_HRTIMER) || defined(CONFIG_SND_HRTIMER_MODULE)
+#define DEFAULT_TIMER_LIMIT 4
 #elif defined(CONFIG_SND_RTCTIMER) || defined(CONFIG_SND_RTCTIMER_MODULE)
 #define DEFAULT_TIMER_LIMIT 2
 #else
 #endif
 
 static int timer_limit = DEFAULT_TIMER_LIMIT;
-MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>, Takashi Iwai <tiwai@suse.de>");
+static int timer_tstamp_monotonic = 1;
+MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
 MODULE_DESCRIPTION("ALSA timer interface");
 MODULE_LICENSE("GPL");
 module_param(timer_limit, int, 0444);
 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
+module_param(timer_tstamp_monotonic, int, 0444);
+MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
+
+MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
+MODULE_ALIAS("devname:snd/timer");
 
 struct snd_timer_user {
        struct snd_timer_instance *timeri;
@@ -130,11 +132,8 @@ static struct snd_timer_instance *snd_timer_instance_new(char *owner,
 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 {
        struct snd_timer *timer = NULL;
-       struct list_head *p;
-
-       list_for_each(p, &snd_timer_list) {
-               timer = list_entry(p, struct snd_timer, device_list);
 
+       list_for_each_entry(timer, &snd_timer_list, device_list) {
                if (timer->tmr_class != tid->dev_class)
                        continue;
                if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
@@ -151,12 +150,10 @@ static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
        return NULL;
 }
 
-#ifdef CONFIG_KMOD
+#ifdef CONFIG_MODULES
 
 static void snd_timer_request(struct snd_timer_id *tid)
 {
-       if (! current->fs->root)
-               return;
        switch (tid->dev_class) {
        case SNDRV_TIMER_CLASS_GLOBAL:
                if (tid->device < timer_limit)
@@ -184,18 +181,14 @@ static void snd_timer_check_slave(struct snd_timer_instance *slave)
 {
        struct snd_timer *timer;
        struct snd_timer_instance *master;
-       struct list_head *p, *q;
 
        /* FIXME: it's really dumb to look up all entries.. */
-       list_for_each(p, &snd_timer_list) {
-               timer = list_entry(p, struct snd_timer, device_list);
-               list_for_each(q, &timer->open_list_head) {
-                       master = list_entry(q, struct snd_timer_instance, open_list);
+       list_for_each_entry(timer, &snd_timer_list, device_list) {
+               list_for_each_entry(master, &timer->open_list_head, open_list) {
                        if (slave->slave_class == master->slave_class &&
                            slave->slave_id == master->slave_id) {
-                               list_del(&slave->open_list);
-                               list_add_tail(&slave->open_list,
-                                             &master->slave_list_head);
+                               list_move_tail(&slave->open_list,
+                                              &master->slave_list_head);
                                spin_lock_irq(&slave_active_lock);
                                slave->master = master;
                                slave->timer = master->timer;
@@ -214,16 +207,13 @@ static void snd_timer_check_slave(struct snd_timer_instance *slave)
  */
 static void snd_timer_check_master(struct snd_timer_instance *master)
 {
-       struct snd_timer_instance *slave;
-       struct list_head *p, *n;
+       struct snd_timer_instance *slave, *tmp;
 
        /* check all pending slaves */
-       list_for_each_safe(p, n, &snd_timer_slave_list) {
-               slave = list_entry(p, struct snd_timer_instance, open_list);
+       list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
                if (slave->slave_class == master->slave_class &&
                    slave->slave_id == master->slave_id) {
-                       list_del(p);
-                       list_add_tail(p, &master->slave_list_head);
+                       list_move_tail(&slave->open_list, &master->slave_list_head);
                        spin_lock_irq(&slave_active_lock);
                        slave->master = master;
                        slave->timer = master->timer;
@@ -272,8 +262,8 @@ int snd_timer_open(struct snd_timer_instance **ti,
        /* open a master instance */
        mutex_lock(&register_mutex);
        timer = snd_timer_find(tid);
-#ifdef CONFIG_KMOD
-       if (timer == NULL) {
+#ifdef CONFIG_MODULES
+       if (!timer) {
                mutex_unlock(&register_mutex);
                snd_timer_request(tid);
                mutex_lock(&register_mutex);
@@ -317,10 +307,10 @@ static int _snd_timer_stop(struct snd_timer_instance *timeri,
 int snd_timer_close(struct snd_timer_instance *timeri)
 {
        struct snd_timer *timer = NULL;
-       struct list_head *p, *n;
-       struct snd_timer_instance *slave;
+       struct snd_timer_instance *slave, *tmp;
 
-       snd_assert(timeri != NULL, return -ENXIO);
+       if (snd_BUG_ON(!timeri))
+               return -ENXIO;
 
        /* force to stop the timer */
        snd_timer_stop(timeri);
@@ -339,6 +329,8 @@ int snd_timer_close(struct snd_timer_instance *timeri)
                mutex_unlock(&register_mutex);
        } else {
                timer = timeri->timer;
+               if (snd_BUG_ON(!timer))
+                       goto out;
                /* wait, until the active callback is finished */
                spin_lock_irq(&timer->lock);
                while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
@@ -353,18 +345,18 @@ int snd_timer_close(struct snd_timer_instance *timeri)
                    timer->hw.close)
                        timer->hw.close(timer);
                /* remove slave links */
-               list_for_each_safe(p, n, &timeri->slave_list_head) {
-                       slave = list_entry(p, struct snd_timer_instance, open_list);
+               list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
+                                        open_list) {
                        spin_lock_irq(&slave_active_lock);
                        _snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
-                       list_del(p);
-                       list_add_tail(p, &snd_timer_slave_list);
+                       list_move_tail(&slave->open_list, &snd_timer_slave_list);
                        slave->master = NULL;
                        slave->timer = NULL;
                        spin_unlock_irq(&slave_active_lock);
                }
                mutex_unlock(&register_mutex);
        }
+ out:
        if (timeri->private_free)
                timeri->private_free(timeri);
        kfree(timeri->owner);
@@ -394,17 +386,20 @@ static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
        unsigned long flags;
        unsigned long resolution = 0;
        struct snd_timer_instance *ts;
-       struct list_head *n;
        struct timespec tstamp;
 
-       getnstimeofday(&tstamp);
-       snd_assert(event >= SNDRV_TIMER_EVENT_START &&
-                  event <= SNDRV_TIMER_EVENT_PAUSE, return);
+       if (timer_tstamp_monotonic)
+               do_posix_clock_monotonic_gettime(&tstamp);
+       else
+               getnstimeofday(&tstamp);
+       if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
+                      event > SNDRV_TIMER_EVENT_PAUSE))
+               return;
        if (event == SNDRV_TIMER_EVENT_START ||
            event == SNDRV_TIMER_EVENT_CONTINUE)
                resolution = snd_timer_resolution(ti);
        if (ti->ccallback)
-               ti->ccallback(ti, SNDRV_TIMER_EVENT_START, &tstamp, resolution);
+               ti->ccallback(ti, event, &tstamp, resolution);
        if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
                return;
        timer = ti->timer;
@@ -413,19 +408,16 @@ static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
        if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
                return;
        spin_lock_irqsave(&timer->lock, flags);
-       list_for_each(n, &ti->slave_active_head) {
-               ts = list_entry(n, struct snd_timer_instance, active_list);
+       list_for_each_entry(ts, &ti->slave_active_head, active_list)
                if (ts->ccallback)
                        ts->ccallback(ti, event + 100, &tstamp, resolution);
-       }
        spin_unlock_irqrestore(&timer->lock, flags);
 }
 
 static int snd_timer_start1(struct snd_timer *timer, struct snd_timer_instance *timeri,
                            unsigned long sticks)
 {
-       list_del(&timeri->active_list);
-       list_add_tail(&timeri->active_list, &timer->active_list_head);
+       list_move_tail(&timeri->active_list, &timer->active_list_head);
        if (timer->running) {
                if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
                        goto __start_now;
@@ -489,7 +481,8 @@ static int _snd_timer_stop(struct snd_timer_instance * timeri,
        struct snd_timer *timer;
        unsigned long flags;
 
-       snd_assert(timeri != NULL, return -ENXIO);
+       if (snd_BUG_ON(!timeri))
+               return -ENXIO;
 
        if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
                if (!keep_flag) {
@@ -542,6 +535,8 @@ int snd_timer_stop(struct snd_timer_instance *timeri)
        if (err < 0)
                return err;
        timer = timeri->timer;
+       if (!timer)
+               return -EINVAL;
        spin_lock_irqsave(&timer->lock, flags);
        timeri->cticks = timeri->ticks;
        timeri->pticks = 0;
@@ -593,10 +588,8 @@ static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_l
 {
        struct snd_timer_instance *ti;
        unsigned long ticks = ~0UL;
-       struct list_head *p;
 
-       list_for_each(p, &timer->active_list_head) {
-               ti = list_entry(p, struct snd_timer_instance, active_list);
+       list_for_each_entry(ti, &timer->active_list_head, active_list) {
                if (ti->flags & SNDRV_TIMER_IFLG_START) {
                        ti->flags &= ~SNDRV_TIMER_IFLG_START;
                        ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
@@ -661,9 +654,9 @@ static void snd_timer_tasklet(unsigned long arg)
  */
 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 {
-       struct snd_timer_instance *ti, *ts;
+       struct snd_timer_instance *ti, *ts, *tmp;
        unsigned long resolution, ticks;
-       struct list_head *p, *q, *n, *ack_list_head;
+       struct list_head *p, *ack_list_head;
        unsigned long flags;
        int use_tasklet = 0;
 
@@ -679,12 +672,12 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
                resolution = timer->hw.resolution;
 
        /* loop for all active instances
-        * Here we cannot use list_for_each because the active_list of a
+        * Here we cannot use list_for_each_entry because the active_list of a
         * processed instance is relinked to done_list_head before the callback
         * is called.
         */
-       list_for_each_safe(p, n, &timer->active_list_head) {
-               ti = list_entry(p, struct snd_timer_instance, active_list);
+       list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
+                                active_list) {
                if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
                        continue;
                ti->pticks += ticks_left;
@@ -700,7 +693,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
                } else {
                        ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
                        if (--timer->running)
-                               list_del(p);
+                               list_del(&ti->active_list);
                }
                if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
                    (ti->flags & SNDRV_TIMER_IFLG_FAST))
@@ -709,8 +702,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
                        ack_list_head = &timer->sack_list_head;
                if (list_empty(&ti->ack_list))
                        list_add_tail(&ti->ack_list, ack_list_head);
-               list_for_each(q, &ti->slave_active_head) {
-                       ts = list_entry(q, struct snd_timer_instance, active_list);
+               list_for_each_entry(ts, &ti->slave_active_head, active_list) {
                        ts->pticks = ti->pticks;
                        ts->resolution = resolution;
                        if (list_empty(&ts->ack_list))
@@ -718,7 +710,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
                }
        }
        if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
-               snd_timer_reschedule(timer, ticks_left);
+               snd_timer_reschedule(timer, timer->sticks);
        if (timer->running) {
                if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
                        timer->hw.stop(timer);
@@ -758,7 +750,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
        spin_unlock_irqrestore(&timer->lock, flags);
 
        if (use_tasklet)
-               tasklet_hi_schedule(&timer->task_queue);
+               tasklet_schedule(&timer->task_queue);
 }
 
 /*
@@ -776,9 +768,10 @@ int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
                .dev_disconnect = snd_timer_dev_disconnect,
        };
 
-       snd_assert(tid != NULL, return -EINVAL);
-       snd_assert(rtimer != NULL, return -EINVAL);
-       *rtimer = NULL;
+       if (snd_BUG_ON(!tid))
+               return -EINVAL;
+       if (rtimer)
+               *rtimer = NULL;
        timer = kzalloc(sizeof(*timer), GFP_KERNEL);
        if (timer == NULL) {
                snd_printk(KERN_ERR "timer: cannot allocate\n");
@@ -806,13 +799,15 @@ int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
                        return err;
                }
        }
-       *rtimer = timer;
+       if (rtimer)
+               *rtimer = timer;
        return 0;
 }
 
 static int snd_timer_free(struct snd_timer *timer)
 {
-       snd_assert(timer != NULL, return -ENXIO);
+       if (!timer)
+               return 0;
 
        mutex_lock(&register_mutex);
        if (! list_empty(&timer->open_list_head)) {
@@ -844,17 +839,15 @@ static int snd_timer_dev_register(struct snd_device *dev)
 {
        struct snd_timer *timer = dev->device_data;
        struct snd_timer *timer1;
-       struct list_head *p;
 
-       snd_assert(timer != NULL && timer->hw.start != NULL &&
-                  timer->hw.stop != NULL, return -ENXIO);
+       if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
+               return -ENXIO;
        if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
            !timer->hw.resolution && timer->hw.c_resolution == NULL)
                return -EINVAL;
 
        mutex_lock(&register_mutex);
-       list_for_each(p, &snd_timer_list) {
-               timer1 = list_entry(p, struct snd_timer, device_list);
+       list_for_each_entry(timer1, &snd_timer_list, device_list) {
                if (timer1->tmr_class > timer->tmr_class)
                        break;
                if (timer1->tmr_class < timer->tmr_class)
@@ -877,7 +870,7 @@ static int snd_timer_dev_register(struct snd_device *dev)
                mutex_unlock(&register_mutex);
                return -EBUSY;
        }
-       list_add_tail(&timer->device_list, p);
+       list_add_tail(&timer->device_list, &timer1->device_list);
        mutex_unlock(&register_mutex);
        return 0;
 }
@@ -896,12 +889,12 @@ void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstam
        unsigned long flags;
        unsigned long resolution = 0;
        struct snd_timer_instance *ti, *ts;
-       struct list_head *p, *n;
 
        if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
                return;
-       snd_assert(event >= SNDRV_TIMER_EVENT_MSTART &&
-                  event <= SNDRV_TIMER_EVENT_MRESUME, return);
+       if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
+                      event > SNDRV_TIMER_EVENT_MRESUME))
+               return;
        spin_lock_irqsave(&timer->lock, flags);
        if (event == SNDRV_TIMER_EVENT_MSTART ||
            event == SNDRV_TIMER_EVENT_MCONTINUE ||
@@ -911,15 +904,12 @@ void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstam
                else
                        resolution = timer->hw.resolution;
        }
-       list_for_each(p, &timer->active_list_head) {
-               ti = list_entry(p, struct snd_timer_instance, active_list);
+       list_for_each_entry(ti, &timer->active_list_head, active_list) {
                if (ti->ccallback)
                        ti->ccallback(ti, event, tstamp, resolution);
-               list_for_each(n, &ti->slave_active_head) {
-                       ts = list_entry(n, struct snd_timer_instance, active_list);
+               list_for_each_entry(ts, &ti->slave_active_head, active_list)
                        if (ts->ccallback)
                                ts->ccallback(ts, event, tstamp, resolution);
-               }
        }
        spin_unlock_irqrestore(&timer->lock, flags);
 }
@@ -959,7 +949,6 @@ int snd_timer_global_register(struct snd_timer *timer)
 
 struct snd_timer_system_private {
        struct timer_list tlist;
-       struct timer * timer;
        unsigned long last_expires;
        unsigned long last_jiffies;
        unsigned long correction;
@@ -1006,6 +995,7 @@ static int snd_timer_s_stop(struct snd_timer * timer)
                timer->sticks = priv->last_expires - jiff;
        else
                timer->sticks = 1;
+       priv->correction = 0;
        return 0;
 }
 
@@ -1057,11 +1047,9 @@ static void snd_timer_proc_read(struct snd_info_entry *entry,
 {
        struct snd_timer *timer;
        struct snd_timer_instance *ti;
-       struct list_head *p, *q;
 
        mutex_lock(&register_mutex);
-       list_for_each(p, &snd_timer_list) {
-               timer = list_entry(p, struct snd_timer, device_list);
+       list_for_each_entry(timer, &snd_timer_list, device_list) {
                switch (timer->tmr_class) {
                case SNDRV_TIMER_CLASS_GLOBAL:
                        snd_iprintf(buffer, "G%i: ", timer->tmr_device);
@@ -1088,14 +1076,12 @@ static void snd_timer_proc_read(struct snd_info_entry *entry,
                if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
                        snd_iprintf(buffer, " SLAVE");
                snd_iprintf(buffer, "\n");
-               list_for_each(q, &timer->open_list_head) {
-                       ti = list_entry(q, struct snd_timer_instance, open_list);
+               list_for_each_entry(ti, &timer->open_list_head, open_list)
                        snd_iprintf(buffer, "  Client %s : %s\n",
                                    ti->owner ? ti->owner : "unknown",
                                    ti->flags & (SNDRV_TIMER_IFLG_START |
                                                 SNDRV_TIMER_IFLG_RUNNING)
                                    ? "running" : "stopped");
-               }
        }
        mutex_unlock(&register_mutex);
 }
@@ -1181,6 +1167,7 @@ static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
 {
        struct snd_timer_user *tu = timeri->callback_data;
        struct snd_timer_tread r1;
+       unsigned long flags;
 
        if (event >= SNDRV_TIMER_EVENT_START &&
            event <= SNDRV_TIMER_EVENT_PAUSE)
@@ -1190,9 +1177,9 @@ static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
        r1.event = event;
        r1.tstamp = *tstamp;
        r1.val = resolution;
-       spin_lock(&tu->qlock);
+       spin_lock_irqsave(&tu->qlock, flags);
        snd_timer_user_append_to_tqueue(tu, &r1);
-       spin_unlock(&tu->qlock);
+       spin_unlock_irqrestore(&tu->qlock, flags);
        kill_fasync(&tu->fasync, SIGIO, POLL_IN);
        wake_up(&tu->qchange_sleep);
 }
@@ -1213,8 +1200,12 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
                spin_unlock(&tu->qlock);
                return;
        }
-       if (tu->last_resolution != resolution || ticks > 0)
-               getnstimeofday(&tstamp);
+       if (tu->last_resolution != resolution || ticks > 0) {
+               if (timer_tstamp_monotonic)
+                       do_posix_clock_monotonic_gettime(&tstamp);
+               else
+                       getnstimeofday(&tstamp);
+       }
        if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
            tu->last_resolution != resolution) {
                r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
@@ -1254,6 +1245,11 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
 static int snd_timer_user_open(struct inode *inode, struct file *file)
 {
        struct snd_timer_user *tu;
+       int err;
+
+       err = nonseekable_open(inode, file);
+       if (err < 0)
+               return err;
 
        tu = kzalloc(sizeof(*tu), GFP_KERNEL);
        if (tu == NULL)
@@ -1280,7 +1276,6 @@ static int snd_timer_user_release(struct inode *inode, struct file *file)
        if (file->private_data) {
                tu = file->private_data;
                file->private_data = NULL;
-               fasync_helper(-1, file, 0, &tu->fasync);
                if (tu->timeri)
                        snd_timer_close(tu->timeri);
                kfree(tu->queue);
@@ -1413,13 +1408,10 @@ static int snd_timer_user_ginfo(struct file *file,
        struct list_head *p;
        int err = 0;
 
-       ginfo = kmalloc(sizeof(*ginfo), GFP_KERNEL);
-       if (! ginfo)
-               return -ENOMEM;
-       if (copy_from_user(ginfo, _ginfo, sizeof(*ginfo))) {
-               kfree(ginfo);
-               return -EFAULT;
-       }
+       ginfo = memdup_user(_ginfo, sizeof(*ginfo));
+       if (IS_ERR(ginfo))
+               return PTR_ERR(ginfo);
+
        tid = ginfo->tid;
        memset(ginfo, 0, sizeof(*ginfo));
        ginfo->tid = tid;
@@ -1580,9 +1572,11 @@ static int snd_timer_user_info(struct file *file,
        int err = 0;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        t = tu->timeri->timer;
-       snd_assert(t != NULL, return -ENXIO);
+       if (!t)
+               return -EBADFD;
 
        info = kzalloc(sizeof(*info), GFP_KERNEL);
        if (! info)
@@ -1610,9 +1604,11 @@ static int snd_timer_user_params(struct file *file,
        int err;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        t = tu->timeri->timer;
-       snd_assert(t != NULL, return -ENXIO);
+       if (!t)
+               return -EBADFD;
        if (copy_from_user(&params, _params, sizeof(params)))
                return -EFAULT;
        if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
@@ -1706,7 +1702,8 @@ static int snd_timer_user_status(struct file *file,
        struct snd_timer_status status;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        memset(&status, 0, sizeof(status));
        status.tstamp = tu->tstamp;
        status.resolution = snd_timer_resolution(tu->timeri);
@@ -1726,7 +1723,8 @@ static int snd_timer_user_start(struct file *file)
        struct snd_timer_user *tu;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        snd_timer_stop(tu->timeri);
        tu->timeri->lost = 0;
        tu->last_resolution = 0;
@@ -1739,7 +1737,8 @@ static int snd_timer_user_stop(struct file *file)
        struct snd_timer_user *tu;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
 }
 
@@ -1749,7 +1748,8 @@ static int snd_timer_user_continue(struct file *file)
        struct snd_timer_user *tu;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        tu->timeri->lost = 0;
        return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
 }
@@ -1760,7 +1760,8 @@ static int snd_timer_user_pause(struct file *file)
        struct snd_timer_user *tu;
 
        tu = file->private_data;
-       snd_assert(tu->timeri != NULL, return -ENXIO);
+       if (!tu->timeri)
+               return -EBADFD;
        return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
 }
 
@@ -1834,13 +1835,9 @@ static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
 static int snd_timer_user_fasync(int fd, struct file * file, int on)
 {
        struct snd_timer_user *tu;
-       int err;
 
        tu = file->private_data;
-       err = fasync_helper(fd, file, on, &tu->fasync);
-        if (err < 0)
-               return err;
-       return 0;
+       return fasync_helper(fd, file, on, &tu->fasync);
 }
 
 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
@@ -1931,12 +1928,13 @@ static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
 #define snd_timer_user_ioctl_compat    NULL
 #endif
 
-static struct file_operations snd_timer_f_ops =
+static const struct file_operations snd_timer_f_ops =
 {
        .owner =        THIS_MODULE,
        .read =         snd_timer_user_read,
        .open =         snd_timer_user_open,
        .release =      snd_timer_user_release,
+       .llseek =       no_llseek,
        .poll =         snd_timer_user_poll,
        .unlocked_ioctl =       snd_timer_user_ioctl,
        .compat_ioctl = snd_timer_user_ioctl_compat,