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: stable@kernel.org Cc: Mark Brown broonie@kernel.org Signed-off-by: Badhri Jagan Sridharan badhri@google.com --- drivers/usb/typec/tcpm/tcpm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index c9a78f55ca48..bbe1381232eb 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -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
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#opti...
Rule: add the tag "Cc: stable@vger.kernel.org" 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
HI all,
Please ignore this patch. Adding the right tag "Cc: stable@vger.kernel.org" for CCing stable.
Thanks, Badhri
On Tue, Feb 27, 2024 at 3:58 PM Badhri Jagan Sridharan badhri@google.com wrote:
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: stable@kernel.org Cc: Mark Brown broonie@kernel.org Signed-off-by: Badhri Jagan Sridharan badhri@google.com
drivers/usb/typec/tcpm/tcpm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index c9a78f55ca48..bbe1381232eb 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -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
linux-stable-mirror@lists.linaro.org