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Date:   Sun,  6 Jun 2021 16:14:52 +0800
Message-Id: <20210606081452.764032-1-kyletso@google.com>
Mime-Version: 1.0
Subject: [PATCH] usb: typec: tcpm: Do not finish VDM AMS for retrying Responses
From:   Kyle Tso <kyletso@google.com>
To:     linux@roeck-us.net, heikki.krogerus@linux.intel.com,
        gregkh@linuxfoundation.org
Cc:     badhri@google.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, Kyle Tso <kyletso@google.com>
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Precedence: bulk

If the VDM responses couldn't be sent successfully, it doesn't need to
finish the AMS until the retry count reaches the limit.

Fixes: 0908c5aca31e ("usb: typec: tcpm: AMS and Collision Avoidance")
Signed-off-by: Kyle Tso <kyletso@google.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 0db685d5d9c0..08fabe1fc31d 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -1965,6 +1965,9 @@ static void vdm_run_state_machine(struct tcpm_port *port)
 			tcpm_log(port, "VDM Tx error, retry");
 			port->vdm_retries++;
 			port->vdm_state = VDM_STATE_READY;
+			if (PD_VDO_SVDM(vdo_hdr) && PD_VDO_CMDT(vdo_hdr) == CMDT_INIT)
+				tcpm_ams_finish(port);
+		} else {
 			tcpm_ams_finish(port);
 		}
 		break;
-- 
2.32.0.rc1.229.g3e70b5a671-goog