[PATCH v3 2/2] usb: typec: tcpm: Fix wrong handling for Not_Supported in VDM AMS

From: Kyle Tso
Date: Fri May 07 2021 - 02:23:25 EST


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>
---
Changes since v2:
- no changes

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