AP_Notify: add driver for LED on Blue Robotics Navigator board

libraries/AP_Notify/AP_Notify.cpp

@@ -21,6 +21,7 @@
 #include "Display.h"
 #include "ExternalLED.h"
 #include "PCA9685LED_I2C.h"
+#include "NavigatorLED.h"
 #include "NeoPixel.h"
 #include "NCP5623.h"
 #include "OreoLED_I2C.h"
@@ -248,7 +249,7 @@ void AP_Notify::add_backends(void)
   #elif CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_DISCO
                 ADD_BACKEND(new DiscoLED());
   #elif CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_NAVIGATOR
-                ADD_BACKEND(new DiscreteRGBLed(HAL_RGBLED_RED, HAL_RGBLED_GREEN, HAL_RGBLED_BLUE, HAL_RGBLED_NORMAL_POLARITY));
+                ADD_BACKEND(new NavigatorLED());
   #endif
 #endif // CONFIG_HAL_BOARD == HAL_BOARD_LINUX
 

libraries/AP_Notify/NavigatorLED.cpp

@@ -0,0 +1,81 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+// This driver is for the neopixel on the Blue Robotics Navigator board
+// designed for the Raspberry Pi 4. The neopixel data in is connected to
+// the Raspberry Pi's MOSI pin. The clock, chip select, and MISO pins are
+// not used. The data is sent to the neopixel in 24 'SPI bytes', where each
+// spi byte is formatted to appear as a single bit of data to the neopixel.
+
+#include <AP_HAL/AP_HAL.h>
+#include "AP_Notify/AP_Notify.h"
+#include "NavigatorLED.h"
+
+#define NEOPIXEL_LED_LOW    0x18
+#define NEOPIXEL_LED_MEDIUM 0x40
+#define NEOPIXEL_LED_HIGH   0xFF
+#define NEOPIXEL_LED_OFF    0x00
+
+#define LED_T0 0b11000000
+#define LED_T1 0b11110000
+
+extern const AP_HAL::HAL& hal;
+
+NavigatorLED::NavigatorLED() :
+    RGBLed(NEOPIXEL_LED_OFF, NEOPIXEL_LED_HIGH, NEOPIXEL_LED_MEDIUM, NEOPIXEL_LED_LOW)
+{
+}
+
+bool NavigatorLED::init()
+{
+    _dev = hal.spi->get_device("led");
+    if (!_dev) {
+        return false;
+    }
+    return true;
+}
+
+bool NavigatorLED::hw_set_rgb(uint8_t red, uint8_t green, uint8_t blue)
+{
+    if (!_dev) {
+        return false;
+    }
+
+    // format our spi bytes to transmit the desired color data
+    _setup_data(red, green, blue);
+
+    // take i2c bus sempahore
+    WITH_SEMAPHORE(_dev->get_semaphore());
+
+    // send the new color data
+    return _dev->transfer(_data, sizeof(_data), nullptr, 0);
+}
+
+// Get our bytes ready to send the desired color data
+// Datasheet: https://cdn-shop.adafruit.com/datasheets/WS2812B.pdf
+// 24bit msg as 3 byte GRB (not RGB) where first bit is G7, and last bit is B0
+// (first) G7|G6|G5|G4|G3|G2|G1|G0|R7|R6|R5|R4|R3|R2|R1|R0|B7|B6|B5|B4|B3|B2|B1|B0 (last)
+void NavigatorLED::_setup_data(uint8_t red, uint8_t green, uint8_t blue)
+{
+    for (uint8_t i = 0; i < 8; i++) {
+        _data[i] = (green & (1<<(7-i))) ? LED_T1 : LED_T0;
+    }
+    for (uint8_t i = 0; i < 8; i++) {
+        _data[8 + i] = (red & (1<<(7-i))) ? LED_T1 : LED_T0;
+    }
+    for (uint8_t i = 0; i < 8; i++) {
+        _data[16 + i] = (blue & (1<<(7-i))) ? LED_T1 : LED_T0;
+    }
+}

libraries/AP_Notify/NavigatorLED.h

@@ -0,0 +1,32 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "RGBLed.h"
+#include <AP_Common/AP_Common.h>
+
+class NavigatorLED: public RGBLed {
+public:
+    NavigatorLED();
+    bool init(void) override;
+
+protected:
+    bool hw_set_rgb(uint8_t r, uint8_t g, uint8_t b) override;
+
+private:
+    uint8_t _data[24];
+    void _setup_data(uint8_t red, uint8_t green, uint8_t blue);
+    AP_HAL::OwnPtr<AP_HAL::SPIDevice> _dev;
+};