[PATCH v2 2/2] usb: typec: tcpm: Fix wrong handling for Not_Supported in VDM AMS

[Kyle Tso]

Not_Supported Message is acceptable in VDM AMS. Redirect the VDM state
machine to VDM_STATE_DONE when receiving Not_Supported and finish the
VDM AMS.

Also, after the loop in vdm_state_machine_work, add more conditions of
VDM states to clear the vdm_sm_running flag because those are all
stopping states when leaving the loop.

In addition, finish the VDM AMS if the port partner responds BUSY.

Fixes: 8dea75e11380 ("usb: typec: tcpm: Protocol Error handling")
Fixes: 8d3a0578ad1a ("usb: typec: tcpm: Respond Wait if VDM state machine is running")
Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx>
---
 drivers/usb/typec/tcpm/tcpm.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 07a449f0e8fa..bf97db232f09 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -1897,7 +1897,6 @@ static void vdm_run_state_machine(struct tcpm_port *port)
 
 			if (res < 0) {
 				port->vdm_state = VDM_STATE_ERR_BUSY;
-				port->vdm_sm_running = false;
 				return;
 			}
 		}
@@ -1913,6 +1912,7 @@ static void vdm_run_state_machine(struct tcpm_port *port)
 		port->vdo_data[0] = port->vdo_retry;
 		port->vdo_count = 1;
 		port->vdm_state = VDM_STATE_READY;
+		tcpm_ams_finish(port);
 		break;
 	case VDM_STATE_BUSY:
 		port->vdm_state = VDM_STATE_ERR_TMOUT;
@@ -1978,7 +1978,7 @@ 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)
+	if (port->vdm_state < VDM_STATE_READY)
 		port->vdm_sm_running = false;
 
 	mutex_unlock(&port->lock);
@@ -2569,6 +2569,16 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
 			port->sink_cap_done = true;
 			tcpm_set_state(port, ready_state(port), 0);
 			break;
+		case SRC_READY:
+		case SNK_READY:
+			if (port->vdm_state > VDM_STATE_READY) {
+				port->vdm_state = VDM_STATE_DONE;
+				if (tcpm_vdm_ams(port))
+					tcpm_ams_finish(port);
+				mod_vdm_delayed_work(port, 0);
+				break;
+			}
+			fallthrough;
 		default:
 			tcpm_pd_handle_state(port,
 					     port->pwr_role == TYPEC_SOURCE ?
-- 
2.31.1.527.g47e6f16901-goog