ASoC: arizona: Export functions to control subsystem DVFS

The WM5102 and WM8997 codecs have an internal dynamic clock booster.
When this booster is active, the DCVDD voltage must be increased.
If all the currently active audio paths can run with the root SYSCLK
we can disable the booster, allowing us to turn down DCVDD voltage
to save power.

Previously this was being done by having the booster enable bit set
as a side-effect of the LDO1 regulator driver, which is unexpected
behaviour of a regulator and not compatible with using an external
regulator.  [Originally this was documented as a feature of the internal
LDO -- broonie]

This patch exports functions to handle the booster enable and
DCVDD voltage, with each relevant subsystem flagging whether it can
currently run without the booster. Note that these subsystems are
stateless and none of them are nestable, so there's no need for
reference counting, we only need a simple boolean for each subsystem
of whether their current condition could require the booster or will
allow us to turn the codec down to lower operating power.

Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/sound/soc/codecs/arizona.h b/sound/soc/codecs/arizona.h
index bacc296a7d72..84e119a56515 100644
--- a/sound/soc/codecs/arizona.h
+++ b/sound/soc/codecs/arizona.h
@@ -60,6 +60,9 @@
 #define ARIZONA_MAX_DAI  6
 #define ARIZONA_MAX_ADSP 4
 
+#define ARIZONA_DVFS_SR1_RQ	0x001
+#define ARIZONA_DVFS_ADSP1_RQ	0x100
+
 struct arizona;
 struct wm_adsp;
 
@@ -84,6 +87,10 @@ struct arizona_priv {
 
 	unsigned int spk_ena:2;
 	unsigned int spk_ena_pending:1;
+
+	unsigned int dvfs_reqs;
+	struct mutex dvfs_lock;
+	bool dvfs_cached;
 };
 
 #define ARIZONA_NUM_MIXER_INPUTS 103
@@ -245,6 +252,12 @@ struct arizona_fll {
 	char clock_ok_name[ARIZONA_FLL_NAME_LEN];
 };
 
+extern int arizona_dvfs_up(struct snd_soc_codec *codec, unsigned int flags);
+extern int arizona_dvfs_down(struct snd_soc_codec *codec, unsigned int flags);
+extern int arizona_dvfs_sysclk_ev(struct snd_soc_dapm_widget *w,
+				  struct snd_kcontrol *kcontrol, int event);
+extern void arizona_init_dvfs(struct arizona_priv *priv);
+
 extern int arizona_init_fll(struct arizona *arizona, int id, int base,
 			    int lock_irq, int ok_irq, struct arizona_fll *fll);
 extern int arizona_set_fll_refclk(struct arizona_fll *fll, int source,