[PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer

[Chang Wu <kunjinkao.jp@gmail.com>]

regulator_is_enabled() reports the aggregate regulator state, not
whether this consumer holds an enable reference. If another consumer
enables VBUS first, the driver can skip its own regulator_enable() call
and later attempt to drop a reference it never acquired, triggering an
unbalanced regulator disable warning.

Track successful enable and disable calls locally. Keep the state
unchanged when an operation fails so a later role or ID notification
retries the operation while this consumer keeps balanced references.

Fixes: b3f9d6e491fd ("usb: typec: hd3ss3220: Check if regulator needs to be switched")
Cc: stable@vger.kernel.org
Link: https://github.com/qualcomm-linux/kernel/issues/472
Signed-off-by: Chang Wu <kunjinkao.jp@gmail.com>
---
Testing:
- scripts/checkpatch.pl --strict: passed
- Qualcomm CI checkpatch, sparse, DT and UAPI checks: passed
- Not tested on hardware

 drivers/usb/typec/hd3ss3220.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/hd3ss3220.c b/drivers/usb/typec/hd3ss3220.c
index d0de5a2488f9..4eec90c82bae 100644
--- a/drivers/usb/typec/hd3ss3220.c
+++ b/drivers/usb/typec/hd3ss3220.c
@@ -62,6 +62,7 @@ struct hd3ss3220 {
 	int id_irq;
 
 	struct regulator *vbus;
+	bool vbus_enabled;
 };
 
 static int hd3ss3220_set_power_opmode(struct hd3ss3220 *hd3ss3220, int power_opmode)
@@ -208,7 +209,7 @@ static void hd3ss3220_regulator_control(struct hd3ss3220 *hd3ss3220, bool on)
 {
 	int ret;
 
-	if (regulator_is_enabled(hd3ss3220->vbus) == on)
+	if (hd3ss3220->vbus_enabled == on)
 		return;
 
 	if (on)
@@ -216,9 +217,13 @@ static void hd3ss3220_regulator_control(struct hd3ss3220 *hd3ss3220, bool on)
 	else
 		ret = regulator_disable(hd3ss3220->vbus);
 
-	if (ret)
+	if (ret) {
 		dev_err(hd3ss3220->dev,
 			"vbus regulator %s failed: %d\n", on ? "enable" : "disable", ret);
+		return;
+	}
+
+	hd3ss3220->vbus_enabled = on;
 }
 
 static void hd3ss3220_set_role(struct hd3ss3220 *hd3ss3220)

base-commit: e1e6e541c5c9cf548e9fdc35fc26808c82074440
-- 
2.48.0