[alsa-devel] [PATCH v2 1/3] ALSA: timer: Simplify timer hw resolution calls
Takashi Iwai
tiwai at suse.de
Thu May 17 10:49:09 CEST 2018
There multiple open-codes to get the hardware timer resolution.
Make a local helper function snd_timer_hw_resolution() and call it
from all relevant places.
There is no functional change by this, just a preliminary work for the
following timer resolution hardening patch.
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
sound/core/timer.c | 33 ++++++++++++++-------------------
1 file changed, 14 insertions(+), 19 deletions(-)
diff --git a/sound/core/timer.c b/sound/core/timer.c
index dc87728c5b74..23b941df9c43 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -427,6 +427,14 @@ int snd_timer_close(struct snd_timer_instance *timeri)
}
EXPORT_SYMBOL(snd_timer_close);
+static unsigned long snd_timer_hw_resolution(struct snd_timer *timer)
+{
+ if (timer->hw.c_resolution)
+ return timer->hw.c_resolution(timer);
+ else
+ return timer->hw.resolution;
+}
+
unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
{
struct snd_timer * timer;
@@ -434,11 +442,8 @@ unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
if (timeri == NULL)
return 0;
timer = timeri->timer;
- if (timer) {
- if (timer->hw.c_resolution)
- return timer->hw.c_resolution(timer);
- return timer->hw.resolution;
- }
+ if (timer)
+ return snd_timer_hw_resolution(timer);
return 0;
}
EXPORT_SYMBOL(snd_timer_resolution);
@@ -771,10 +776,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
spin_lock_irqsave(&timer->lock, flags);
/* remember the current resolution */
- if (timer->hw.c_resolution)
- resolution = timer->hw.c_resolution(timer);
- else
- resolution = timer->hw.resolution;
+ resolution = snd_timer_hw_resolution(timer);
/* loop for all active instances
* Here we cannot use list_for_each_entry because the active_list of a
@@ -1014,12 +1016,8 @@ void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstam
spin_lock_irqsave(&timer->lock, flags);
if (event == SNDRV_TIMER_EVENT_MSTART ||
event == SNDRV_TIMER_EVENT_MCONTINUE ||
- event == SNDRV_TIMER_EVENT_MRESUME) {
- if (timer->hw.c_resolution)
- resolution = timer->hw.c_resolution(timer);
- else
- resolution = timer->hw.resolution;
- }
+ event == SNDRV_TIMER_EVENT_MRESUME)
+ resolution = snd_timer_hw_resolution(timer);
list_for_each_entry(ti, &timer->active_list_head, active_list) {
if (ti->ccallback)
ti->ccallback(ti, event, tstamp, resolution);
@@ -1656,10 +1654,7 @@ static int snd_timer_user_gstatus(struct file *file,
mutex_lock(®ister_mutex);
t = snd_timer_find(&tid);
if (t != NULL) {
- if (t->hw.c_resolution)
- gstatus.resolution = t->hw.c_resolution(t);
- else
- gstatus.resolution = t->hw.resolution;
+ gstatus.resolution = snd_timer_hw_resolution(t);
if (t->hw.precise_resolution) {
t->hw.precise_resolution(t, &gstatus.resolution_num,
&gstatus.resolution_den);
--
2.16.3
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