usb: typec: tcpm: Fix wrong handling for Not_Supported in VDM AMS

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")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Kyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210507062300.1945009-3-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index ae1e842..db567e6 100644 (file)
--- 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 ?