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Sender: "badhri via sendgmr" <badhri@badhri.mtv.corp.google.com>
Date:   Mon,  1 Feb 2021 02:02:12 -0800
Message-Id: <20210201100212.49863-1-badhri@google.com>
Mime-Version: 1.0
Subject: [PATCH v1] usb: typec: tcpm: Handle vbus shutoff when in source mode
From:   Badhri Jagan Sridharan <badhri@google.com>
To:     Guenter Roeck <linux@roeck-us.net>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Kyle Tso <kyletso@google.com>
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        Badhri Jagan Sridharan <badhri@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

While in source mode, vbus could be shutoff by protections
circuits. TCPM does not move back to toggling state to
re-initiate connection. Fix this by moving to SRC_UNATTACHED
state when vbus shuts off while in source mode.

Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 0afd8ef692e8..ff0732c12b8a 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4897,6 +4897,17 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port)
 		/* Do nothing, waiting for sink detection */
 		break;
 
+	case SRC_STARTUP:
+	case SRC_SEND_CAPABILITIES:
+	case SRC_SEND_CAPABILITIES_TIMEOUT:
+	case SRC_NEGOTIATE_CAPABILITIES:
+	case SRC_TRANSITION_SUPPLY:
+	case SRC_READY:
+	case SRC_WAIT_NEW_CAPABILITIES:
+		/* Force to unattached state to re-initiate connection */
+		tcpm_set_state(port, SRC_UNATTACHED, 0);
+		break;
+
 	case PORT_RESET:
 		/*
 		 * State set back to default mode once the timer completes.
-- 
2.30.0.365.g02bc693789-goog