From afb92ad8733ef0a2843cc229e4d96aead80bc429 Mon Sep 17 00:00:00 2001 From: Amit Sunil Dhamne Date: Wed, 23 Oct 2024 19:22:30 -0700 Subject: [PATCH] usb: typec: tcpm: restrict SNK_WAIT_CAPABILITIES_TIMEOUT transitions to non self-powered devices PD3.1 spec ("8.3.3.3.3 PE_SNK_Wait_for_Capabilities State") mandates that the policy engine perform a hard reset when SinkWaitCapTimer expires. Instead the code explicitly does a GET_SOURCE_CAP when the timer expires as part of SNK_WAIT_CAPABILITIES_TIMEOUT. Due to this the following compliance test failures are reported by the compliance tester (added excerpts from the PD Test Spec): * COMMON.PROC.PD.2#1: The Tester receives a Get_Source_Cap Message from the UUT. This message is valid except the following conditions: [COMMON.PROC.PD.2#1] a. The check fails if the UUT sends this message before the Tester has established an Explicit Contract ... * TEST.PD.PROT.SNK.4: ... 4. The check fails if the UUT does not send a Hard Reset between tTypeCSinkWaitCap min and max. [TEST.PD.PROT.SNK.4#1] The delay is between the VBUS present vSafe5V min and the time of the first bit of Preamble of the Hard Reset sent by the UUT. For the purpose of interoperability, restrict the quirk introduced in https://lore.kernel.org/all/20240523171806.223727-1-sebastian.reichel@collabora.com/ to only non self-powered devices as battery powered devices will not have the issue mentioned in that commit. Cc: stable@vger.kernel.org Fixes: 122968f8dda8 ("usb: typec: tcpm: avoid resets for missing source capability messages") Reported-by: Badhri Jagan Sridharan Closes: https://lore.kernel.org/all/CAPTae5LAwsVugb0dxuKLHFqncjeZeJ785nkY4Jfd+M-tCjHSnQ@mail.gmail.com/ Signed-off-by: Amit Sunil Dhamne Reviewed-by: Badhri Jagan Sridharan Reviewed-by: Heikki Krogerus Tested-by: Xu Yang Reviewed-by: Sebastian Reichel Link: https://lore.kernel.org/r/20241024022233.3276995-1-amitsd@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/tcpm/tcpm.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index fc619478200f..7ae341a40342 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -4515,7 +4515,8 @@ static inline enum tcpm_state hard_reset_state(struct tcpm_port *port) return ERROR_RECOVERY; if (port->pwr_role == TYPEC_SOURCE) return SRC_UNATTACHED; - if (port->state == SNK_WAIT_CAPABILITIES_TIMEOUT) + if (port->state == SNK_WAIT_CAPABILITIES || + port->state == SNK_WAIT_CAPABILITIES_TIMEOUT) return SNK_READY; return SNK_UNATTACHED; } @@ -5043,8 +5044,11 @@ static void run_state_machine(struct tcpm_port *port) tcpm_set_state(port, SNK_SOFT_RESET, PD_T_SINK_WAIT_CAP); } else { - tcpm_set_state(port, SNK_WAIT_CAPABILITIES_TIMEOUT, - PD_T_SINK_WAIT_CAP); + if (!port->self_powered) + upcoming_state = SNK_WAIT_CAPABILITIES_TIMEOUT; + else + upcoming_state = hard_reset_state(port); + tcpm_set_state(port, upcoming_state, PD_T_SINK_WAIT_CAP); } break; case SNK_WAIT_CAPABILITIES_TIMEOUT: