ASoC: cs42l42: Don't rely on GPIOD_OUT_LOW to set RESET initially low
authorRichard Fitzgerald <rf@opensource.cirrus.com>
Wed, 13 Sep 2023 15:00:11 +0000 (16:00 +0100)
committerMark Brown <broonie@kernel.org>
Wed, 13 Sep 2023 15:03:20 +0000 (16:03 +0100)
The ACPI setting for a GPIO default state has higher priority than the
flag passed to devm_gpiod_get_optional() so ACPI can override the
GPIOD_OUT_LOW. Explicitly set the GPIO low when hard resetting.

Although GPIOD_OUT_LOW can't be relied on this doesn't seem like a
reason to stop passing it to devm_gpiod_get_optional(). So we still pass
it to state our intent, but can deal with it having no effect.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230913150012.604775-3-sbinding@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/codecs/cs42l42.c

index 56d2857..dc93861 100644 (file)
@@ -2321,6 +2321,12 @@ int cs42l42_common_probe(struct cs42l42_private *cs42l42,
        if (cs42l42->reset_gpio) {
                dev_dbg(cs42l42->dev, "Found reset GPIO\n");
 
+               /*
+                * ACPI can override the default GPIO state we requested
+                * so ensure that we start with RESET low.
+                */
+               gpiod_set_value_cansleep(cs42l42->reset_gpio, 0);
+
                /* Ensure minimum reset pulse width */
                usleep_range(10, 500);