2024-04-23 20:27:47

by RD Babiera

Subject: [PATCH v1] usb: typec: tcpm: clear pd_event queue in PORT_RESET

When a Fast Role Swap control message attempt results in a transition
to ERROR_RECOVERY, the TCPC can still queue a TCPM_SOURCING_VBUS event.

If the event is queued but processed after the tcpm_reset_port() call
in the PORT_RESET state, then the following occurs:
1. tcpm_reset_port() calls tcpm_init_vbus() to reset the vbus sourcing and
sinking state
2. tcpm_pd_event_handler() turns VBUS on before the port is in the default
state.
3. The port resolves as a sink. In the SNK_DISCOVERY state,
tcpm_set_charge() cannot set vbus to charge.

Clear pd events within PORT_RESET to get rid of non-applicable events.

Fixes: b17dd57118fe ("staging: typec: tcpm: Improve role swap with non PD capable partners")
Cc: [email protected]
Signed-off-by: RD Babiera <[email protected]>
---
drivers/usb/typec/tcpm/tcpm.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index c26fb70c3ec6..6dcafbaf10a2 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5605,6 +5605,7 @@ static void run_state_machine(struct tcpm_port *port)
break;
case PORT_RESET:
tcpm_reset_port(port);
+ port->pd_events = 0;
if (port->self_powered)
tcpm_set_cc(port, TYPEC_CC_OPEN);
else

base-commit: 684e9f5f97eb4b7831298ffad140d5c1d426ff27
--
2.44.0.769.g3c40516874-goog

2024-04-25 14:09:37

by Heikki Krogerus

Subject: Re: [PATCH v1] usb: typec: tcpm: clear pd_event queue in PORT_RESET

On Tue, Apr 23, 2024 at 08:27:16PM +0000, RD Babiera wrote:
> When a Fast Role Swap control message attempt results in a transition
> to ERROR_RECOVERY, the TCPC can still queue a TCPM_SOURCING_VBUS event.
>
> If the event is queued but processed after the tcpm_reset_port() call
> in the PORT_RESET state, then the following occurs:
> 1. tcpm_reset_port() calls tcpm_init_vbus() to reset the vbus sourcing and
> sinking state
> 2. tcpm_pd_event_handler() turns VBUS on before the port is in the default
> state.
> 3. The port resolves as a sink. In the SNK_DISCOVERY state,
> tcpm_set_charge() cannot set vbus to charge.
>
> Clear pd events within PORT_RESET to get rid of non-applicable events.
>
> Fixes: b17dd57118fe ("staging: typec: tcpm: Improve role swap with non PD capable partners")
> Cc: [email protected]
> Signed-off-by: RD Babiera <[email protected]>

Reviewed-by: Heikki Krogerus <[email protected]>

> ---
> drivers/usb/typec/tcpm/tcpm.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index c26fb70c3ec6..6dcafbaf10a2 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -5605,6 +5605,7 @@ static void run_state_machine(struct tcpm_port *port)
> break;
> case PORT_RESET:
> tcpm_reset_port(port);
> + port->pd_events = 0;
> if (port->self_powered)
> tcpm_set_cc(port, TYPEC_CC_OPEN);
> else
>
> base-commit: 684e9f5f97eb4b7831298ffad140d5c1d426ff27
> --
> 2.44.0.769.g3c40516874-goog

--
heikki