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usb: typec: tpcm: Fix PORT_RESET behavior for self powered devices

PATCH In review Badhri Jagan Sridharan 3 participants 3 messages Feb 28, 2024 – Mar 12, 2024

Subsystems (4)
Stable branch USB USB Type-C class USB Type-C port controller drivers
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Badhri Jagan Sridharan

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#0 lore raw

PATCH v2 1/1 usb: typec: tpcm: Fix PORT_RESET behavior for self powered devices

While commit 69f89168b310 ("usb: typec: tpcm: Fix issues with power being removed during reset") fixes the boot issues for bus powered devices such as LibreTech Renegade Elite/Firefly, it trades off the CC pins NOT being Hi-Zed during errory recovery (i.e PORT_RESET) for devices which are NOT bus powered(a.k.a self powered). This change Hi-Zs the CC pins only for self powered devices, thus preventing brown out for bus powered devices

Adhering to spec is gaining more importance due to the Common charger initiative enforced by the European Union.

Quoting from the spec:
4.5.2.2.2.1 ErrorRecovery State Requirements
The port shall not drive VBUS or VCONN, and shall present a high-impedance to ground (above zOPEN) on its CC1 and CC2 pins.

Hi-Zing the CC pins is the inteded behavior for PORT_RESET. CC pins are set to default state after tErrorRecovery in PORT_RESET_WAIT_OFF.

4.5.2.2.2.2 Exiting From ErrorRecovery State
A Sink shall transition to Unattached.SNK after tErrorRecovery. A Source shall transition to Unattached.SRC after tErrorRecovery.

Fixes 69f89168b310 ("usb: typec: tpcm: Fix issues with power being removed during reset")
Cc [email protected]
Cc Mark Brown <[email protected]>
Signed-off-by Badhri Jagan Sridharan <[email protected]>

---
Changes since V1:
* Fix CC for linux stable

---
 drivers/usb/typec/tcpm/tcpm.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
drivers/usb/typec/tcpm/tcpm.c +5 -2
index c9a78f55ca48..bbe1381232eb 100644
@@ -5593,8 +5593,11 @@ static void run_state_machine(struct tcpm_port *port)
 		break;
 	case PORT_RESET:
 		tcpm_reset_port(port);
-		tcpm_set_cc(port, tcpm_default_state(port) == SNK_UNATTACHED ?
-			    TYPEC_CC_RD : tcpm_rp_cc(port));
+		if (port->self_powered)
+			tcpm_set_cc(port, TYPEC_CC_OPEN);
+		else
+			tcpm_set_cc(port, tcpm_default_state(port) == SNK_UNATTACHED ?
+				    TYPEC_CC_RD : tcpm_rp_cc(port));
 		tcpm_set_state(port, PORT_RESET_WAIT_OFF,
 			       PD_T_ERROR_RECOVERY);
 		break;

base-commit: a560a5672826fc1e057068bda93b3d4c98d037a2

Signature · 1 line
2.44.0.rc1.240.g4c46232300-goog
Tested-by on v2 1/1
#1 lore raw
Quoted 6 lines · Badhri Jagan Sridharan

While commit 69f89168b310 ("usb: typec: tpcm: Fix issues with power being removed during reset") fixes the boot issues for bus powered devices such as LibreTech Renegade Elite/Firefly, it trades off the CC pins NOT being Hi-Zed during errory recovery (i.e PORT_RESET) for devices which are NOT bus powered(a.k.a self powered). This change Hi-Zs the CC pins only for self powered devices, thus preventing brown out for bus powered devices

Tested-by Mark Brown <[email protected]>
maintainer Acked-by on v2 1/1
#2 lore raw
In reply to Badhri Jagan Sridharan
Quoted 19 lines · Badhri Jagan Sridharan

While commit 69f89168b310 ("usb: typec: tpcm: Fix issues with power being removed during reset") fixes the boot issues for bus powered devices such as LibreTech Renegade Elite/Firefly, it trades off the CC pins NOT being Hi-Zed during errory recovery (i.e PORT_RESET) for devices which are NOT bus powered(a.k.a self powered). This change Hi-Zs the CC pins only for self powered devices, thus preventing brown out for bus powered devices

Adhering to spec is gaining more importance due to the Common charger initiative enforced by the European Union.

Quoting from the spec:
4.5.2.2.2.1 ErrorRecovery State Requirements
The port shall not drive VBUS or VCONN, and shall present a high-impedance to ground (above zOPEN) on its CC1 and CC2 pins.

Hi-Zing the CC pins is the inteded behavior for PORT_RESET. CC pins are set to default state after tErrorRecovery in PORT_RESET_WAIT_OFF.

Quoted 8 lines

4.5.2.2.2.2 Exiting From ErrorRecovery State
A Sink shall transition to Unattached.SNK after tErrorRecovery. A Source shall transition to Unattached.SRC after tErrorRecovery.

Fixes 69f89168b310 ("usb: typec: tpcm: Fix issues with power being removed during reset")
Cc [email protected]
Cc Mark Brown <[email protected]>
Signed-off-by Badhri Jagan Sridharan <[email protected]>
Acked-by Heikki Krogerus <[email protected]>
Quoted 29 lines

---
Changes since V1:
* Fix CC for linux stable

---
 drivers/usb/typec/tcpm/tcpm.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
drivers/usb/typec/tcpm/tcpm.c +5 -2
index c9a78f55ca48..bbe1381232eb 100644
@@ -5593,8 +5593,11 @@ static void run_state_machine(struct tcpm_port *port)
 		break;
 	case PORT_RESET:
 		tcpm_reset_port(port);
-		tcpm_set_cc(port, tcpm_default_state(port) == SNK_UNATTACHED ?
-			    TYPEC_CC_RD : tcpm_rp_cc(port));
+		if (port->self_powered)
+			tcpm_set_cc(port, TYPEC_CC_OPEN);
+		else
+			tcpm_set_cc(port, tcpm_default_state(port) == SNK_UNATTACHED ?
+				    TYPEC_CC_RD : tcpm_rp_cc(port));
 		tcpm_set_state(port, PORT_RESET_WAIT_OFF,
 			       PD_T_ERROR_RECOVERY);
 		break;

base-commit: a560a5672826fc1e057068bda93b3d4c98d037a2

Signature · 1 line
2.44.0.rc1.240.g4c46232300-goog
Signature · 1 line
heikki