[PATCH v5 3/3] usb: typec: tcpm: Respond Wait if VDM state machine is running
From: Kyle Tso
Date: Tue Jan 05 2021 - 11:41:49 EST
Port partner could send PR_SWAP/DR_SWAP/VCONN_SWAP/Request just after it
enters Ready states. This will cause conficts if the port is going to
send DISC_IDENT in the Ready states of TCPM. Set a flag indicating that
the state machine is processing VDM and respond Wait messages until the
VDM state machine stops.
Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx>
Signed-off-by: Will McVicker <willmcvicker@xxxxxxxxxx>
---
drivers/usb/typec/tcpm/tcpm.c | 80 ++++++++++++++++++++++++++++++++---
1 file changed, 73 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index a951307d669d..9aa0e36f87e9 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -352,6 +352,7 @@ struct tcpm_port {
struct hrtimer enable_frs_timer;
struct kthread_work enable_frs;
bool state_machine_running;
+ bool vdm_sm_running;
struct completion tx_complete;
enum tcpm_transmit_status tx_status;
@@ -1527,6 +1528,7 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
rlen = 1;
} else {
tcpm_register_partner_altmodes(port);
+ port->vdm_sm_running = false;
}
break;
case CMD_ENTER_MODE:
@@ -1570,10 +1572,12 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
rlen = 1;
break;
}
+ port->vdm_sm_running = false;
break;
default:
response[0] = p[0] | VDO_CMDT(CMDT_RSP_NAK);
rlen = 1;
+ port->vdm_sm_running = false;
break;
}
@@ -1740,6 +1744,8 @@ static void vdm_run_state_machine(struct tcpm_port *port)
switch (PD_VDO_CMD(vdo_hdr)) {
case CMD_DISCOVER_IDENT:
res = tcpm_ams_start(port, DISCOVER_IDENTITY);
+ if (res == 0)
+ port->send_discover = false;
break;
case CMD_DISCOVER_SVID:
res = tcpm_ams_start(port, DISCOVER_SVIDS);
@@ -1766,8 +1772,10 @@ static void vdm_run_state_machine(struct tcpm_port *port)
break;
}
- if (res < 0)
+ if (res < 0) {
+ port->vdm_sm_running = false;
return;
+ }
}
port->vdm_state = VDM_STATE_SEND_MESSAGE;
@@ -1846,6 +1854,9 @@ static void vdm_state_machine_work(struct kthread_work *work)
port->vdm_state != VDM_STATE_BUSY &&
port->vdm_state != VDM_STATE_SEND_MESSAGE);
+ if (port->vdm_state == VDM_STATE_ERR_TMOUT)
+ port->vdm_sm_running = false;
+
mutex_unlock(&port->lock);
}
@@ -2230,6 +2241,12 @@ static void tcpm_pd_data_request(struct tcpm_port *port,
}
port->sink_request = le32_to_cpu(msg->payload[0]);
+
+ if (port->vdm_sm_running && port->explicit_contract) {
+ tcpm_pd_handle_msg(port, PD_MSG_CTRL_WAIT, port->ams);
+ break;
+ }
+
if (port->state == SRC_SEND_CAPABILITIES)
tcpm_set_state(port, SRC_NEGOTIATE_CAPABILITIES, 0);
else
@@ -2335,6 +2352,10 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
TYPEC_PWR_MODE_PD,
port->pps_data.active,
port->supply_voltage);
+ /* Set VDM running flag ASAP */
+ if (port->data_role == TYPEC_HOST &&
+ port->send_discover)
+ port->vdm_sm_running = true;
tcpm_set_state(port, SNK_READY, 0);
} else {
/*
@@ -2372,10 +2393,14 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
switch (port->state) {
case SNK_NEGOTIATE_CAPABILITIES:
/* USB PD specification, Figure 8-43 */
- if (port->explicit_contract)
+ if (port->explicit_contract) {
next_state = SNK_READY;
- else
+ if (port->data_role == TYPEC_HOST &&
+ port->send_discover)
+ port->vdm_sm_running = true;
+ } else {
next_state = SNK_WAIT_CAPABILITIES;
+ }
tcpm_set_state(port, next_state, 0);
break;
case SNK_NEGOTIATE_PPS_CAPABILITIES:
@@ -2384,6 +2409,11 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
port->pps_data.op_curr = port->current_limit;
port->pps_status = (type == PD_CTRL_WAIT ?
-EAGAIN : -EOPNOTSUPP);
+
+ if (port->data_role == TYPEC_HOST &&
+ port->send_discover)
+ port->vdm_sm_running = true;
+
tcpm_set_state(port, SNK_READY, 0);
break;
case DR_SWAP_SEND:
@@ -2440,6 +2470,10 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
}
break;
case DR_SWAP_SEND:
+ if (port->data_role == TYPEC_DEVICE &&
+ port->send_discover)
+ port->vdm_sm_running = true;
+
tcpm_set_state(port, DR_SWAP_CHANGE_DR, 0);
break;
case PR_SWAP_SEND:
@@ -2470,28 +2504,45 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
* 6.3.9: If an alternate mode is active, a request to swap
* alternate modes shall trigger a port reset.
*/
- if (port->typec_caps.data != TYPEC_PORT_DRD)
+ if (port->typec_caps.data != TYPEC_PORT_DRD) {
tcpm_pd_handle_msg(port,
port->negotiated_rev < PD_REV30 ?
PD_MSG_CTRL_REJECT :
PD_MSG_CTRL_NOT_SUPP,
NONE_AMS);
- else
+ } else {
+ if (port->vdm_sm_running) {
+ tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
+ break;
+ }
+
tcpm_pd_handle_state(port, DR_SWAP_ACCEPT,
DATA_ROLE_SWAP, 0);
+ }
break;
case PD_CTRL_PR_SWAP:
- if (port->port_type != TYPEC_PORT_DRP)
+ if (port->port_type != TYPEC_PORT_DRP) {
tcpm_pd_handle_msg(port,
port->negotiated_rev < PD_REV30 ?
PD_MSG_CTRL_REJECT :
PD_MSG_CTRL_NOT_SUPP,
NONE_AMS);
- else
+ } else {
+ if (port->vdm_sm_running) {
+ tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
+ break;
+ }
+
tcpm_pd_handle_state(port, PR_SWAP_ACCEPT,
POWER_ROLE_SWAP, 0);
+ }
break;
case PD_CTRL_VCONN_SWAP:
+ if (port->vdm_sm_running) {
+ tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
+ break;
+ }
+
tcpm_pd_handle_state(port, VCONN_SWAP_ACCEPT, VCONN_SWAP, 0);
break;
case PD_CTRL_GET_SOURCE_CAP_EXT:
@@ -3359,6 +3410,7 @@ static void tcpm_reset_port(struct tcpm_port *port)
}
port->in_ams = false;
port->ams = NONE_AMS;
+ port->vdm_sm_running = false;
tcpm_unregister_altmodes(port);
tcpm_typec_disconnect(port);
port->attached = false;
@@ -4157,6 +4209,9 @@ static void run_state_machine(struct tcpm_port *port)
break;
case DR_SWAP_ACCEPT:
tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
+ /* Set VDM state machine running flag ASAP */
+ if (port->data_role == TYPEC_DEVICE && port->send_discover)
+ port->vdm_sm_running = true;
tcpm_set_state_cond(port, DR_SWAP_CHANGE_DR, 0);
break;
case DR_SWAP_SEND_TIMEOUT:
@@ -4312,6 +4367,8 @@ static void run_state_machine(struct tcpm_port *port)
break;
case VCONN_SWAP_SEND_TIMEOUT:
tcpm_swap_complete(port, -ETIMEDOUT);
+ if (port->data_role == TYPEC_HOST && port->send_discover)
+ port->vdm_sm_running = true;
tcpm_set_state(port, ready_state(port), 0);
break;
case VCONN_SWAP_START:
@@ -4327,10 +4384,14 @@ static void run_state_machine(struct tcpm_port *port)
case VCONN_SWAP_TURN_ON_VCONN:
tcpm_set_vconn(port, true);
tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
+ if (port->data_role == TYPEC_HOST && port->send_discover)
+ port->vdm_sm_running = true;
tcpm_set_state(port, ready_state(port), 0);
break;
case VCONN_SWAP_TURN_OFF_VCONN:
tcpm_set_vconn(port, false);
+ if (port->data_role == TYPEC_HOST && port->send_discover)
+ port->vdm_sm_running = true;
tcpm_set_state(port, ready_state(port), 0);
break;
@@ -4338,6 +4399,8 @@ static void run_state_machine(struct tcpm_port *port)
case PR_SWAP_CANCEL:
case VCONN_SWAP_CANCEL:
tcpm_swap_complete(port, port->swap_status);
+ if (port->data_role == TYPEC_HOST && port->send_discover)
+ port->vdm_sm_running = true;
if (port->pwr_role == TYPEC_SOURCE)
tcpm_set_state(port, SRC_READY, 0);
else
@@ -4668,6 +4731,9 @@ static void _tcpm_pd_vbus_on(struct tcpm_port *port)
switch (port->state) {
case SNK_TRANSITION_SINK_VBUS:
port->explicit_contract = true;
+ /* Set the VDM flag ASAP */
+ if (port->data_role == TYPEC_HOST && port->send_discover)
+ port->vdm_sm_running = true;
tcpm_set_state(port, SNK_READY, 0);
break;
case SNK_DISCOVERY:
--
2.29.2.729.g45daf8777d-goog