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

PATCH Superseded Badhri Jagan Sridharan 2 participants 3 messages Feb 27, 2024 – Feb 28, 2024

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

v1 of 2 Superseded Latest is v2 →

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Badhri Jagan Sridharan

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#0 lore raw

PATCH 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]>
---
 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
build bot
#1 lore raw
FYI: kernel test robot notices the stable kernel rule is not satisfied.

Hi,

Thanks for your patch.

FYI: kernel test robot notices the stable kernel rule is not satisfied.

The check is based on https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html#option-1

Rule: add the tag "Cc: [email protected]" in the sign-off area to have the patch automatically included in the stable tree.
Subject: [PATCH v1] usb: typec: tpcm: Fix PORT_RESET behavior for self powered devices

Link https://lore.kernel.org/stable/20240227235832.744908-1-badhri%40google.com open here
Signature · 2 lines
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
author maintainer
#2 lore raw
In reply to Badhri Jagan Sridharan

HI all,

Please ignore this patch. Adding the right tag "Cc:
[email protected]" for CCing stable.

Thanks,
Badhri

Quoted 55 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.

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]>
---
 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 --
2.44.0.rc1.240.g4c46232300-goog