diff options
| -rw-r--r-- | common/usb_pd_protocol.c | 19 | ||||
| -rw-r--r-- | common/usbc/usb_tc_drp_acc_trysrc_sm.c | 19 | ||||
| -rw-r--r-- | include/config.h | 16 |
3 files changed, 41 insertions, 13 deletions
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c index 29b07a0767..4c480c4bed 100644 --- a/common/usb_pd_protocol.c +++ b/common/usb_pd_protocol.c @@ -426,13 +426,20 @@ static void set_vconn(int port, int enable) ppc_set_vconn(port, 0); /* - * We always need to tell the TCPC to enable Vconn first, otherwise some - * TCPCs get confused when a PPC sets secondary CC line to 5V and TCPC - * immediately disconnect. If there is a PPC, both devices will - * potentially source Vconn, but that should be okay since Vconn has - * "make before break" electrical requirements when swapping anyway. + * Some TCPCs/PPC combinations can trigger OVP if the TCPC doesn't + * source VCONN. This happens if the TCPC will trip OVP with 5V, and the + * PPC doesn't isolate the TCPC from VCONN when sourcing. But, some PPCs + * which do isolate the TCPC can't handle 5V on its host-side CC pins, + * so the TCPC shouldn't source VCONN in those cases. + * + * In the first case, both TCPC and PPC will potentially source Vconn, + * but that should be okay since Vconn has "make before break" + * electrical requirements when swapping anyway. + * + * See b/72961003 and b/180973460 */ - tcpm_set_vconn(port, enable); + if (IS_ENABLED(CONFIG_USB_PD_TCPC_VCONN)) + tcpm_set_vconn(port, enable); if (IS_ENABLED(CONFIG_USBC_PPC_VCONN) && enable) ppc_set_vconn(port, 1); diff --git a/common/usbc/usb_tc_drp_acc_trysrc_sm.c b/common/usbc/usb_tc_drp_acc_trysrc_sm.c index 30f1d6ac85..b45d7377d6 100644 --- a/common/usbc/usb_tc_drp_acc_trysrc_sm.c +++ b/common/usbc/usb_tc_drp_acc_trysrc_sm.c @@ -1692,13 +1692,20 @@ static void set_vconn(int port, int enable) ppc_set_vconn(port, 0); /* - * We always need to tell the TCPC to enable Vconn first, otherwise some - * TCPCs get confused and think the CC line is in over voltage mode and - * immediately disconnects. If there is a PPC, both devices will - * potentially source Vconn, but that should be okay since Vconn has - * "make before break" electrical requirements when swapping anyway. + * Some TCPCs/PPC combinations can trigger OVP if the TCPC doesn't + * source VCONN. This happens if the TCPC will trip OVP with 5V, and the + * PPC doesn't isolate the TCPC from VCONN when sourcing. But, some PPCs + * which do isolate the TCPC can't handle 5V on its host-side CC pins, + * so the TCPC shouldn't source VCONN in those cases. + * + * In the first case, both TCPC and PPC will potentially source Vconn, + * but that should be okay since Vconn has "make before break" + * electrical requirements when swapping anyway. + * + * See b/72961003 and b/180973460 */ - tcpm_set_vconn(port, enable); + if (IS_ENABLED(CONFIG_USB_PD_TCPC_VCONN)) + tcpm_set_vconn(port, enable); if (IS_ENABLED(CONFIG_USBC_PPC_VCONN) && enable) ppc_set_vconn(port, 1); diff --git a/include/config.h b/include/config.h index a7177856b3..1d6181e135 100644 --- a/include/config.h +++ b/include/config.h @@ -4180,6 +4180,9 @@ /* Define EC and TCPC modules are in one integrated chip */ #undef CONFIG_USB_PD_TCPC_ON_CHIP +/* If VCONN is enabled, the TCPC will provide VCONN */ +#define CONFIG_USB_PD_TCPC_VCONN + /* Enable the encoding of msg SOP* in bits 31-28 of 32-bit msg header type */ #undef CONFIG_USB_PD_DECODE_SOP @@ -5345,10 +5348,21 @@ #define CONFIG_USBC_PPC_VCONN #endif -/* The SYV682X supports VCONN and needs to be informed of CC polarity */ +/* + * The SYV682X supports VCONN and needs to be informed of CC polarity. + * There is a 3.6V limit on the HOST_CC signals, so the TCPC should not source + * 5V VCONN. + * + * For the ITE integrated TCPC, it wants to be notified of VCONN but won't + * source VCONN itself, so is safe to keep enabled. + */ #if defined(CONFIG_USBC_PPC_SYV682X) #define CONFIG_USBC_PPC_POLARITY #define CONFIG_USBC_PPC_VCONN +#if !defined(CONFIG_USB_PD_TCPM_DRIVER_IT83XX) && \ + !defined(CONFIG_USB_PD_TCPM_DRIVER_IT8XXX2) +#undef CONFIG_USB_PD_TCPC_VCONN +#endif #endif /*****************************************************************************/ |