diff options
| -rw-r--r-- | common/usb_pd_protocol.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c index 89885c3e84..12b1546217 100644 --- a/common/usb_pd_protocol.c +++ b/common/usb_pd_protocol.c @@ -329,15 +329,17 @@ static void set_polarity(int port, int polarity) #ifdef CONFIG_USBC_VCONN static void set_vconn(int port, int enable) { -#ifdef CONFIG_USBC_PPC /* - * USB-C PPCs can source their own Vconn. No need to tell the TCPC - * to source its own. + * 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. */ - ppc_set_vconn(port, enable); -#else /* !defined(CONFIG_USBC_PPC) */ tcpm_set_vconn(port, enable); -#endif /* defined(CONFIG_USBC_PPC) */ +#ifdef CONFIG_USBC_PPC + ppc_set_vconn(port, enable); +#endif } #endif /* defined(CONFIG_USBC_VCONN) */ |