[PATCH v2, 1/1] usb: typec: tcpm: PSSourceOffTimer timeout in PR_Swap enters ERROR_RECOVERY

[PATCH v2, 1/1] usb: typec: tcpm: PSSourceOffTimer timeout in PR_Swap enters ERROR_RECOVERY

[joswang]

From: Jos Wang <joswang@lenovo.com>

As PD2.0 spec ("6.5.6.2 PSSourceOffTimer")，the PSSourceOffTimer is
used by the Policy Engine in Dual-Role Power device that is currently
acting as a Sink to timeout on a PS_RDY Message during a Power Role
Swap sequence. This condition leads to a Hard Reset for USB Type-A and
Type-B Plugs and Error Recovery for Type-C plugs and return to USB
Default Operation.

Therefore, after PSSourceOffTimer timeout, the tcpm state machine should
switch from PR_SWAP_SNK_SRC_SINK_OFF to ERROR_RECOVERY. This can also
solve the test items in the USB power delivery compliance test:
TEST.PD.PROT.SNK.12 PR_Swap – PSSourceOffTimer Timeout

[1] https://usb.org/document-library/usb-power-delivery-compliance-test-specification-0/USB_PD3_CTS_Q4_2025_OR.zip

Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable@vger.kernel.org
Signed-off-by: Jos Wang <joswang@lenovo.com>
---
v2: Modify the commit message, remove unnecessary blank lines.
 drivers/usb/typec/tcpm/tcpm.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 47be450d2be3..6bf1a22c785a 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5591,8 +5591,7 @@ static void run_state_machine(struct tcpm_port *port)
 		tcpm_set_auto_vbus_discharge_threshold(port, TYPEC_PWR_MODE_USB,
 						       port->pps_data.active, 0);
 		tcpm_set_charge(port, false);
-		tcpm_set_state(port, hard_reset_state(port),
-			       port->timings.ps_src_off_time);
+		tcpm_set_state(port, ERROR_RECOVERY, port->timings.ps_src_off_time);
 		break;
 	case PR_SWAP_SNK_SRC_SOURCE_ON:
 		tcpm_enable_auto_vbus_discharge(port, true);
-- 
2.17.1

Re: [PATCH v2, 1/1] usb: typec: tcpm: PSSourceOffTimer timeout in PR_Swap enters ERROR_RECOVERY

[Heikki Krogerus]

On Thu, Feb 13, 2025 at 09:49:21PM +0800, joswang wrote:
> From: Jos Wang <joswang@lenovo.com>
> 
> As PD2.0 spec ("6.5.6.2 PSSourceOffTimer")，the PSSourceOffTimer is
> used by the Policy Engine in Dual-Role Power device that is currently
> acting as a Sink to timeout on a PS_RDY Message during a Power Role
> Swap sequence. This condition leads to a Hard Reset for USB Type-A and
> Type-B Plugs and Error Recovery for Type-C plugs and return to USB
> Default Operation.
> 
> Therefore, after PSSourceOffTimer timeout, the tcpm state machine should
> switch from PR_SWAP_SNK_SRC_SINK_OFF to ERROR_RECOVERY. This can also
> solve the test items in the USB power delivery compliance test:
> TEST.PD.PROT.SNK.12 PR_Swap – PSSourceOffTimer Timeout
> 
> [1] https://usb.org/document-library/usb-power-delivery-compliance-test-specification-0/USB_PD3_CTS_Q4_2025_OR.zip
> 
> Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
> Cc: stable@vger.kernel.org
> Signed-off-by: Jos Wang <joswang@lenovo.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> v2: Modify the commit message, remove unnecessary blank lines.
>  drivers/usb/typec/tcpm/tcpm.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 47be450d2be3..6bf1a22c785a 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -5591,8 +5591,7 @@ static void run_state_machine(struct tcpm_port *port)
>  		tcpm_set_auto_vbus_discharge_threshold(port, TYPEC_PWR_MODE_USB,
>  						       port->pps_data.active, 0);
>  		tcpm_set_charge(port, false);
> -		tcpm_set_state(port, hard_reset_state(port),
> -			       port->timings.ps_src_off_time);
> +		tcpm_set_state(port, ERROR_RECOVERY, port->timings.ps_src_off_time);
>  		break;
>  	case PR_SWAP_SNK_SRC_SOURCE_ON:
>  		tcpm_enable_auto_vbus_discharge(port, true);
> -- 
> 2.17.1

-- 
heikki