Add sk6812rgbw support (#666)

* Removed -HUP so the default -TERM signal is sent instead.
- hyperiond only listens for TERM and INT. HUP is often used to get an exe to reread its config

Changed pgrep to add '-x' so it wont partial match on the exe name.
- I have multiple instances with multiple hyperiond-instance1 names
- this ensures the service script only kills the right process

* reversing errant change to hyperion.systemd.sh

* adding support for SK6812 - not working yet

* Changed rpi_ws281x submodule to be penfold42's fork

* Set White to zero for now

* starting on the code to make the White led do stuff

* Added some basic whie led calculation
white = min(r,g,b)
r-=w, g-=w, b-=w

* cleaned up a couple of compiler warnings

* updated strip type to use corrected RGBW strip type
(the SK6812RGBW datasheet is wrong)

* moved bitpair_to_byte initialiser to (hopefully) work with older GCC

* compiler warning in udp driver
removed some tabs in ws2812b.cpp

* formatting - spaces to tabs

* moved rpi_281x to tag sk6812-v1.0

* attempt #3 at migrating the rpi_281x submodule to my fork/branch

* moving to my fork of rpi_281x

* Started implementing multiple RGB to RGBW conversion options

a quick hack has been implemented inside WS281x.cpp but ive started
moving this to RgbToRgbw.cpp for reuse by other led device types

* migrated RGB to RGBW conversion to RgbToRgbw.cpp


Former-commit-id: ff8e9038c4bb8203b71b42d12bf23be4abcc0b3b

libsrc/leddevice/LedDeviceFactory.cpp

@@ -363,8 +363,11 @@ LedDevice * LedDeviceFactory::construct(const Json::Value & deviceConfig)
 		const int dmanum = deviceConfig.get("dmanum", 5).asInt();
                 const int pwmchannel = deviceConfig.get("pwmchannel", 0).asInt();
 		const int invert = deviceConfig.get("invert", 0).asInt();
+		const int rgbw = deviceConfig.get("rgbw", 0).asInt();
+		const std::string& whiteAlgorithm = deviceConfig.get("white_algorithm","").asString();
 
-		LedDeviceWS281x * ledDeviceWS281x = new LedDeviceWS281x(gpio, leds, freq, dmanum, pwmchannel, invert);
+		LedDeviceWS281x * ledDeviceWS281x = new LedDeviceWS281x(gpio, leds, freq, dmanum, pwmchannel, invert, 
+			rgbw, whiteAlgorithm);
 		device = ledDeviceWS281x;
 	}
 #endif

libsrc/leddevice/LedDeviceWS281x.cpp

@@ -3,8 +3,11 @@
 #include "LedDeviceWS281x.h"
 
 // Constructor
-LedDeviceWS281x::LedDeviceWS281x(const int gpio, const int leds, const uint32_t freq, const int dmanum, const int pwmchannel, const int invert)
+LedDeviceWS281x::LedDeviceWS281x(const int gpio, const int leds, const uint32_t freq, const int dmanum, const int pwmchannel, const int invert, const int rgbw, const std::string& whiteAlgorithm)
 {
+	_whiteAlgorithm = whiteAlgorithm;
+std::cout << "whiteAlgorithm :" << whiteAlgorithm << ":\n";
+
 	initialized = false;
 	led_string.freq = freq;
 	led_string.dmanum = dmanum;
@@ -17,7 +20,11 @@ LedDeviceWS281x::LedDeviceWS281x(const int gpio, const int leds, const uint32_t
 	led_string.channel[chan].invert = invert;
 	led_string.channel[chan].count = leds;
 	led_string.channel[chan].brightness = 255;
-	led_string.channel[chan].strip_type = WS2811_STRIP_RGB;
+	if (rgbw == 1) {
+		led_string.channel[chan].strip_type = SK6812_STRIP_GRBW;
+	} else {
+		led_string.channel[chan].strip_type = WS2811_STRIP_RGB;
+	}
 
 	led_string.channel[!chan].gpionum = 0;
 	led_string.channel[!chan].invert = invert;
@@ -42,7 +49,19 @@ int LedDeviceWS281x::write(const std::vector<ColorRgb> &ledValues)
 	{
 		if (idx >= led_string.channel[chan].count)
 			break;
-		led_string.channel[chan].leds[idx++] = ((uint32_t)color.red << 16) + ((uint32_t)color.green << 8) + color.blue;
+
+		_temp_rgbw.red = color.red;
+		_temp_rgbw.green = color.green;
+		_temp_rgbw.blue = color.blue;
+		_temp_rgbw.white = 0;
+
+		if (led_string.channel[chan].strip_type == SK6812_STRIP_GRBW) {
+			Rgb_to_Rgbw(color, &_temp_rgbw, _whiteAlgorithm);
+		}
+
+		led_string.channel[chan].leds[idx++] = 
+			((uint32_t)_temp_rgbw.white << 24) + ((uint32_t)_temp_rgbw.red << 16) + ((uint32_t)_temp_rgbw.green << 8) + _temp_rgbw.blue;
+
 	}
 	while (idx < led_string.channel[chan].count)
 		led_string.channel[chan].leds[idx++] = 0;

libsrc/leddevice/LedDeviceWS281x.h

@@ -18,9 +18,11 @@ public:
 	/// @param dmanum The DMA channel to use, default is 5
 	/// @param pwmchannel The pwm channel to use
 	/// @param invert Invert the output line to support an inverting level shifter
+	/// @param rgbw   Send 32 bit rgbw colour data for sk6812
 
 	///
-	LedDeviceWS281x(const int gpio, const int leds, const uint32_t freq, int dmanum, int pwmchannel, int invert);
+	LedDeviceWS281x(const int gpio, const int leds, const uint32_t freq, int dmanum, int pwmchannel, int invert, 
+		int rgbw, const std::string& whiteAlgorithm);
 
 	///
 	/// Destructor of the LedDevice, waits for DMA to complete and then cleans up
@@ -42,6 +44,8 @@ private:
 	ws2811_t led_string;
 	int chan;
 	bool initialized;
+        std::string _whiteAlgorithm;
+	ColorRgbw _temp_rgbw;
 };
 
 #endif /* LEDDEVICEWS281X_H_ */