Commit 1cd7b935 authored Oct 27, 2020 by Charles Keepax Committed by Lee Jones Nov 19, 2020

mfd: madera: Add reset as part of resume



The DCVDD supply does not always power down when the CODEC enters
suspend, for example shared regulators or always-on regulators. In
these cases if a register is written back to the default value whilst
the CODEC is in suspend that register will retain the previous value.
As DCVDD never powered down, the register retains its old value and
as the cache sync only synchronises registers that differ from the
default the new value is never written out.

Ensure the registers are in the expected state after suspend by always
resetting the CODEC on resume. This also has the benefit of being
recommended by the datasheet for DCVDD supplies that take longer than
2mS to rise.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

parent 21ca0f5b

drivers/mfd/madera-core.c

+15 −1

Original line number	Diff line number	Diff line
		@@ -291,6 +291,8 @@ static int __maybe_unused madera_runtime_resume(struct device *dev)

		dev_dbg(dev, "Leaving sleep mode\n");

		madera_enable_hard_reset(madera);

		ret = regulator_enable(madera->dcvdd);
		if (ret) {
		dev_err(dev, "Failed to enable DCVDD: %d\n", ret);
		@@ -300,7 +302,19 @@ static int __maybe_unused madera_runtime_resume(struct device *dev)
		regcache_cache_only(madera->regmap, false);
		regcache_cache_only(madera->regmap_32bit, false);

		usleep_range(MADERA_RESET_MIN_US, MADERA_RESET_MAX_US);
		madera_disable_hard_reset(madera);

		if (!madera->pdata.reset) {
		ret = madera_wait_for_boot(madera);
		if (ret)
		goto err;

		ret = madera_soft_reset(madera);
		if (ret) {
		dev_err(dev, "Failed to reset: %d\n", ret);
		goto err;
		}
		}

		ret = madera_wait_for_boot(madera);
		if (ret)

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