* Re: [PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer
2026-08-19 15:20 [PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer Chang Wu
@ 2026-08-24 11:20 ` Heikki Krogerus
2026-08-25 12:39 ` Jan Remmet
2026-08-26 10:29 ` Krishna Kurapati
2 siblings, 0 replies; 4+ messages in thread
From: Heikki Krogerus @ 2026-08-24 11:20 UTC (permalink / raw)
To: Chang Wu; +Cc: Greg Kroah-Hartman, Jan Remmet, linux-usb, linux-kernel, stable
On Wed, Aug 19, 2026 at 11:20:27PM +0800, Chang Wu wrote:
> 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>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.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
--
heikki
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer
2026-08-19 15:20 [PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer Chang Wu
2026-08-24 11:20 ` Heikki Krogerus
@ 2026-08-25 12:39 ` Jan Remmet
2026-08-26 10:29 ` Krishna Kurapati
2 siblings, 0 replies; 4+ messages in thread
From: Jan Remmet @ 2026-08-25 12:39 UTC (permalink / raw)
To: Chang Wu, Heikki Krogerus, Greg Kroah-Hartman
Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
stable@vger.kernel.org
Am 19.08.26 um 17:20 schrieb Chang Wu:
> 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>
tested on our i.MX95 devboard with switching device / host scenarios.
Tested-by: Jan Remmet <j.remmet@phytec.de>
> ---
> 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
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer
2026-08-19 15:20 [PATCH] usb: typec: hd3ss3220: track VBUS enable state per consumer Chang Wu
2026-08-24 11:20 ` Heikki Krogerus
2026-08-25 12:39 ` Jan Remmet
@ 2026-08-26 10:29 ` Krishna Kurapati
2 siblings, 0 replies; 4+ messages in thread
From: Krishna Kurapati @ 2026-08-26 10:29 UTC (permalink / raw)
To: Chang Wu, Heikki Krogerus, Greg Kroah-Hartman
Cc: Jan Remmet, linux-usb, linux-kernel, stable
On 8/19/2026 8:50 PM, Chang Wu wrote:
> 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>
Reviewed-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.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
^ permalink raw reply [flat|nested] 4+ messages in thread