[PATCH v3 15/15] ASoC: cs42l42: Wait for PLL to lock before switching to it

From: Lucas Tanure
Date: Sat Mar 06 2021 - 14:14:31 EST


From: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>

The PLL should have locked before using it to supply MCLK.

Signed-off-by: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Lucas Tanure <tanureal@xxxxxxxxxxxxxxxxxxxxx>
---
Changes in v3:
- No changes

Changes in v2:
- Lucas signed-off added

sound/soc/codecs/cs42l42.c | 12 +++++++++++-
sound/soc/codecs/cs42l42.h | 2 ++
2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c
index d7a314aa59b73..bf982e145e945 100644
--- a/sound/soc/codecs/cs42l42.c
+++ b/sound/soc/codecs/cs42l42.c
@@ -862,6 +862,7 @@ static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
unsigned int regval;
u8 fullScaleVol;
+ int ret;

if (mute) {
/* Mute the headphone */
@@ -887,9 +888,18 @@ static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
} else {
if (!cs42l42->stream_use) {
/* SCLK must be running before codec unmute */
- if ((cs42l42->bclk < 11289600) && (cs42l42->sclk < 11289600))
+ if ((cs42l42->bclk < 11289600) && (cs42l42->sclk < 11289600)) {
snd_soc_component_update_bits(component, CS42L42_PLL_CTL1,
CS42L42_PLL_START_MASK, 1);
+ ret = regmap_read_poll_timeout(cs42l42->regmap,
+ CS42L42_PLL_LOCK_STATUS,
+ regval,
+ (regval & 1),
+ CS42L42_PLL_LOCK_POLL_US,
+ CS42L42_PLL_LOCK_TIMEOUT_US);
+ if (ret < 0)
+ dev_warn(component->dev, "PLL failed to lock: %d\n", ret);
+ }

/* Mark SCLK as present, turn off internal oscillator */
regmap_multi_reg_write(cs42l42->regmap, cs42l42_to_sclk_seq,
diff --git a/sound/soc/codecs/cs42l42.h b/sound/soc/codecs/cs42l42.h
index 214cee762709d..36b763f0d1a06 100644
--- a/sound/soc/codecs/cs42l42.h
+++ b/sound/soc/codecs/cs42l42.h
@@ -756,6 +756,8 @@
#define CS42L42_NUM_SUPPLIES 5
#define CS42L42_BOOT_TIME_US 3000
#define CS42L42_CLOCK_SWITCH_DELAY_US 150
+#define CS42L42_PLL_LOCK_POLL_US 250
+#define CS42L42_PLL_LOCK_TIMEOUT_US 1250

static const char *const cs42l42_supply_names[CS42L42_NUM_SUPPLIES] = {
"VA",
--
2.30.1