| Message ID | 20231116083221.1201892-1-guanyulin@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | usb: typec: tcpm: skip checking port->send_discover in PD3.0 | expand |
On Thu, Nov 16, 2023 at 04:32:16PM +0800, Guan-Yu Lin wrote: > The original Collison Avoidance mechanism, port->send_discover, avoids > the conflict when port partners start AMS almost the same time. However, > this mechanism is replaced by SINK_TX_OK and SINK_TX_NG. Skip the check > in PD3.0 to avoid the deadlock when source is requesting DR_SWAP where > sink is requesting DISCOVER_IDENTITY. > > Signed-off-by: Guan-Yu Lin <guanyulin@google.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > drivers/usb/typec/tcpm/tcpm.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index 058d5b853b57..ff3c171a3a75 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -2847,7 +2847,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > PD_MSG_CTRL_NOT_SUPP, > NONE_AMS); > } else { > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > @@ -2863,7 +2863,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > PD_MSG_CTRL_NOT_SUPP, > NONE_AMS); > } else { > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > @@ -2872,7 +2872,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > } > break; > case PD_CTRL_VCONN_SWAP: > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > -- > 2.43.0.rc0.421.g78406f8d94-goog
On 11/16/23 00:32, Guan-Yu Lin wrote: > The original Collison Avoidance mechanism, port->send_discover, avoids > the conflict when port partners start AMS almost the same time. However, > this mechanism is replaced by SINK_TX_OK and SINK_TX_NG. Skip the check > in PD3.0 to avoid the deadlock when source is requesting DR_SWAP where > sink is requesting DISCOVER_IDENTITY. > > Signed-off-by: Guan-Yu Lin <guanyulin@google.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > drivers/usb/typec/tcpm/tcpm.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index 058d5b853b57..ff3c171a3a75 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -2847,7 +2847,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > PD_MSG_CTRL_NOT_SUPP, > NONE_AMS); > } else { > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > @@ -2863,7 +2863,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > PD_MSG_CTRL_NOT_SUPP, > NONE_AMS); > } else { > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > @@ -2872,7 +2872,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > } > break; > case PD_CTRL_VCONN_SWAP: > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > }
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 058d5b853b57..ff3c171a3a75 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -2847,7 +2847,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, PD_MSG_CTRL_NOT_SUPP, NONE_AMS); } else { - if (port->send_discover) { + if (port->send_discover && port->negotiated_rev < PD_REV30) { tcpm_queue_message(port, PD_MSG_CTRL_WAIT); break; } @@ -2863,7 +2863,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, PD_MSG_CTRL_NOT_SUPP, NONE_AMS); } else { - if (port->send_discover) { + if (port->send_discover && port->negotiated_rev < PD_REV30) { tcpm_queue_message(port, PD_MSG_CTRL_WAIT); break; } @@ -2872,7 +2872,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, } break; case PD_CTRL_VCONN_SWAP: - if (port->send_discover) { + if (port->send_discover && port->negotiated_rev < PD_REV30) { tcpm_queue_message(port, PD_MSG_CTRL_WAIT); break; }
The original Collison Avoidance mechanism, port->send_discover, avoids the conflict when port partners start AMS almost the same time. However, this mechanism is replaced by SINK_TX_OK and SINK_TX_NG. Skip the check in PD3.0 to avoid the deadlock when source is requesting DR_SWAP where sink is requesting DISCOVER_IDENTITY. Signed-off-by: Guan-Yu Lin <guanyulin@google.com> --- drivers/usb/typec/tcpm/tcpm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)