On Wed, Oct 23, 2024 at 07:22:30PM -0700, Amit Sunil Dhamne wrote:
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@collab... 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 badhri@google.com Closes: https://lore.kernel.org/all/CAPTae5LAwsVugb0dxuKLHFqncjeZeJ785nkY4Jfd+M-tCjH... Signed-off-by: Amit Sunil Dhamne amitsd@google.com Reviewed-by: Badhri Jagan Sridharan badhri@google.com
Tested-by: Xu Yang xu.yang_2@nxp.com
Thanks, Xu Yang
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 d6f2412381cf..c8f467d24fbb 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)} @@ -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;elseupcoming_state = hard_reset_state(port);tcpm_set_state(port, upcoming_state, PD_T_SINK_WAIT_CAP);base-commit: c6d9e43954bfa7415a1e9efdb2806ec1d8a8afc8
2.47.0.105.g07ac214952-goog