From: Dmitry Osipenko <digetx@gmail.com>
Date: Thu, 21 Oct 2021 21:33:08 +0300
Subject: regulator: Don't error out fixed regulator in
 regulator_sync_voltage()

Git-commit: 400d5a5da43c0e84e5aa75151082ea91f0fae3c9
Patch-mainline: v5.16-rc1
References: git-fixes

Fixed regulator can't change voltage and regulator_sync_voltage()
returns -EINVAL in this case. Make regulator_sync_voltage() to succeed
for regulators that are incapable to change voltage.

On NVIDIA Tegra power management driver needs to sync voltage and we have
one device (Trimslice) that uses fixed regulator which is getting synced.
The syncing error isn't treated as fatal, but produces a noisy error
message. This patch silences that error.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20211021183308.27786-1-digetx@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
 drivers/regulator/core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 21a2b28ab0ca..f6ca2098cc01 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -4249,6 +4249,9 @@ int regulator_sync_voltage(struct regulator *regulator)
 	struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
 	int ret, min_uV, max_uV;
 
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
+		return 0;
+
 	regulator_lock(rdev);
 
 	if (!rdev->desc->ops->set_voltage &&
-- 
2.31.1