usb: typec: ucsi: Fix a deadlock in ucsi_send_command_common()

The function returns with the ppm_lock held if the PPM is
busy or there's an error.

Reported-and-tested-by: Luciano Coelho <[email protected]>
Fixes: 5e9c166 ("usb: typec: ucsi: rework command execution functions")
Signed-off-by: Heikki Krogerus <[email protected]>
Reported-by: Luciano Coelho <[email protected]>
Signed-off-by: Luca Coelho <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Heikki Krogerus

drivers/usb/typec/ucsi/ucsi.c

@@ -238,13 +238,10 @@ static int ucsi_send_command_common(struct ucsi *ucsi, u64 cmd,
 	mutex_lock(&ucsi->ppm_lock);
 
 	ret = ucsi_run_command(ucsi, cmd, &cci, data, size, conn_ack);
-	if (cci & UCSI_CCI_BUSY) {
-		ret = ucsi_run_command(ucsi, UCSI_CANCEL, &cci, NULL, 0, false);
-		return ret ? ret : -EBUSY;
-	}
-
-	if (cci & UCSI_CCI_ERROR)
-		return ucsi_read_error(ucsi, connector_num);
+	if (cci & UCSI_CCI_BUSY)
+		ret = ucsi_run_command(ucsi, UCSI_CANCEL, &cci, NULL, 0, false) ?: -EBUSY;
+	else if (cci & UCSI_CCI_ERROR)
+		ret = ucsi_read_error(ucsi, connector_num);
 
 	mutex_unlock(&ucsi->ppm_lock);
 	return ret;