[PATCH 3/3] ASoC: tas2770: Initialise SDZ GPIO low

[James Calligeros]

On Apple Silicon machines integrating TAS2770, the SDZ pin of all
codecs is connected to a shared GPIO line. The kernel's shared
GPIO infrastructure relies on the first change of the GPIO state
being marked as its "default" state, and allows any consumer of the
shared line to assert that state without consensus from other
consumers.

If the pin is initialised high, the shared GPIO core does not
allow the line to be asserted without consensus. This breaks
resuming from suspend on Apple Silicon machines; the driver attempts
to restore the codec's register state and fails because other
codecs are still holding the line low.

Initialise the SDZ GPIO low so that the first state change on probe
asserts it high, allowing any codec to pull the line up when
it needs to.

Signed-off-by: James Calligeros <jcalligeros99 at gmail.com>
---
 sound/soc/codecs/tas2770.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/tas2770.c b/sound/soc/codecs/tas2770.c
index e79754edac5c..ecc37d4ac00b 100644
--- a/sound/soc/codecs/tas2770.c
+++ b/sound/soc/codecs/tas2770.c
@@ -886,7 +886,7 @@ static int tas2770_parse_dt(struct device *dev, struct tas2770_priv *tas2770)
 	if (rc)
 		tas2770->pdm_slot = -1;
 
-	tas2770->sdz_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
+	tas2770->sdz_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_LOW);
 	if (IS_ERR(tas2770->sdz_gpio)) {
 		if (PTR_ERR(tas2770->sdz_gpio) == -EPROBE_DEFER)
 			return -EPROBE_DEFER;

-- 
2.55.0