From fd39d5b9a12c5cc69eb679ec39ca701bd1989352 Mon Sep 17 00:00:00 2001
From: Jacob Dahl <37091262+dakejahl@users.noreply.github.com>
Date: Fri, 8 Oct 2021 13:30:41 -0800
Subject: [PATCH] drivers/distance_sensor/lightware_laser_serial: add LW20/C
 support

---
 .../lightware_laser_serial.cpp                      | 13 +++++++++++++
 .../lightware_laser_serial/parameters.c             |  3 +++
 2 files changed, 16 insertions(+)

diff --git a/src/drivers/distance_sensor/lightware_laser_serial/lightware_laser_serial.cpp b/src/drivers/distance_sensor/lightware_laser_serial/lightware_laser_serial.cpp
index c6e7571492..359a62f575 100644
--- a/src/drivers/distance_sensor/lightware_laser_serial/lightware_laser_serial.cpp
+++ b/src/drivers/distance_sensor/lightware_laser_serial/lightware_laser_serial.cpp
@@ -127,6 +127,13 @@ LightwareLaserSerial::init()
 		_simple_serial = true;
 		break;
 
+	case 8:
+		/* LW20/c (100M 20Hz) */
+		_px4_rangefinder.set_min_distance(0.2f);
+		_px4_rangefinder.set_max_distance(100.0f);
+		_interval = 50000;
+		break;
+
 	default:
 		PX4_ERR("invalid HW model %" PRIi32 ".", hw_model);
 		return -1;
@@ -297,6 +304,12 @@ void LightwareLaserSerial::Run()
 		if ((termios_state = tcsetattr(_fd, TCSANOW, &uart_config)) < 0) {
 			PX4_ERR("baud %d ATTR", termios_state);
 		}
+
+		// LW20: Enable serial mode by sending some characters
+		if (hw_model == 8) {
+			const char *data = "www\r\n";
+			(void)!::write(_fd, &data, strlen(data));
+		}
 	}
 
 	/* collection phase? */
diff --git a/src/drivers/distance_sensor/lightware_laser_serial/parameters.c b/src/drivers/distance_sensor/lightware_laser_serial/parameters.c
index a59d80600c..f8b2c01a8e 100644
--- a/src/drivers/distance_sensor/lightware_laser_serial/parameters.c
+++ b/src/drivers/distance_sensor/lightware_laser_serial/parameters.c
@@ -41,5 +41,8 @@
  * @value 3 SF10/b
  * @value 4 SF10/c
  * @value 5 SF11/c
+ * @value 6 SF30/b
+ * @value 7 SF30/c
+ * @value 8 LW20/c
  */
 PARAM_DEFINE_INT32(SENS_EN_SF0X, 1);