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 --- include/sound/soc-dapm.h | 2 ++ sound/soc/soc-dapm.c | 15 +++++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/include/sound/soc-dapm.h b/include/sound/soc-dapm.h index c080635..e2853da 100644 --- a/include/sound/soc-dapm.h +++ b/include/sound/soc-dapm.h @@ -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); diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index e6a0882..c39146d 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -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