ASoC: Only run power_check() on a widget once per run

Some widgets will get power_check() run on them more than once during a
DAPM run, most commonly due to supply widgets checking to see if their
consumers are powered up. It's wasteful to do this so cache the result
of power_check() during a run. For one system I tested this on I got an
improvement of:

           Power    Path   Neighbour
Before:    106      970    1186
After:     69       727    905

from this.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Mark Brown 2011-10-04 22:15:59 +01:00
parent 75c1f891b4
commit 9b8a83b205
2 changed files with 15 additions and 2 deletions

View file

@ -473,6 +473,8 @@ struct snd_soc_dapm_widget {
unsigned char ext:1; /* has external widgets */
unsigned char force:1; /* force state */
unsigned char ignore_suspend:1; /* kept enabled over suspend */
unsigned char new_power:1; /* power from this run */
unsigned char power_checked:1; /* power checked this run */
int subseq; /* sort within widget type */
int (*power_check)(struct snd_soc_dapm_widget *w);

View file

@ -787,10 +787,17 @@ EXPORT_SYMBOL_GPL(dapm_reg_event);
static int dapm_widget_power_check(struct snd_soc_dapm_widget *w)
{
if (w->power_checked)
return w->new_power;
if (w->force)
return 1;
w->new_power = 1;
else
return w->power_check(w);
w->new_power = w->power_check(w);
w->power_checked = true;
return w->new_power;
}
/* Generic check to see if a widget should be powered.
@ -1322,6 +1329,10 @@ static int dapm_power_widgets(struct snd_soc_dapm_context *dapm, int event)
memset(&card->dapm_stats, 0, sizeof(card->dapm_stats));
list_for_each_entry(w, &card->widgets, list) {
w->power_checked = false;
}
/* Check which widgets we need to power and store them in
* lists indicating if they should be powered up or down. We
* only check widgets that have been flagged as dirty but note