Add new WS281x driver

Add a new WS281x driver which is a wrapper around jgarff's ws281x library which
works on Pi B+, Pi 2, Pi Zero and probably Pi 3 as well.

jgarff's ws281x library is included as a submodule


Former-commit-id: e473dfd36d31b14598da5e56e4b8bf9f2aa7bb24

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "dependencies/external/protobuf"]
 	path = dependencies/external/protobuf
 	url = https://github.com/tvdzwan/protobuf.git
+[submodule "dependencies/external/rpi_ws281x"]
+	path = dependencies/external/rpi_ws281x
+	url = https://github.com/jgarff/rpi_ws281x

CMakeLists.txt

@@ -34,6 +34,9 @@ message(STATUS "ENABLE_V4L2 = " ${ENABLE_V4L2})
 option(ENABLE_WS2812BPWM   "Enable the WS2812b-PWM device" OFF)
 message(STATUS "ENABLE_WS2812BPWM = " ${ENABLE_WS2812BPWM})
 
+option(ENABLE_WS281XPWM   "Enable the WS281x-PWM device" OFF)
+message(STATUS "ENABLE_WS281XPWM = " ${ENABLE_WS281XPWM})
+
 option(ENABLE_X11 "Enable the X11 grabber" OFF)
 message(STATUS "ENABLE_X11 = " ${ENABLE_X11})
 
@@ -56,6 +59,10 @@ if(ENABLE_OSX AND ENABLE_DISPMANX)
 	message(FATAL_ERROR "dispmanx grabber and osx grabber cannot be used at the same time")
 endif(ENABLE_OSX AND ENABLE_DISPMANX)
 
+if(ENABLE_WS2812BPWM AND ENABLE_WS281XPWM)
+	message(FATAL_ERROR "WS2812b and WS281x drivers cannot be used at the same time")
+endif(ENABLE_WS2812BPWM AND ENABLE_WS281XPWM)
+
 #if(ENABLE_QT5)
 # TODO vs ENABLE_QT4?
 #endif(ENABLE_QT5)

HyperionConfig.h.in

@@ -12,6 +12,9 @@
 // Define to enable the ws2812b-pwm-device
 #cmakedefine ENABLE_WS2812BPWM
 
+// Define to enable the ws281x-pwm-via-dma-device using jgarff's library
+#cmakedefine ENABLE_WS281XPWM
+
 // Define to enable the spi-device
 #cmakedefine ENABLE_TINKERFORGE
 

dependencies/CMakeLists.txt

@@ -4,6 +4,13 @@ add_subdirectory(build/jsoncpp)
 add_subdirectory(build/serial)
 add_subdirectory(build/tinkerforge)
 
+if(ENABLE_WS281XPWM)
+	add_library(ws281x
+		external/rpi_ws281x/mailbox.c external/rpi_ws281x/ws2811.c
+		external/rpi_ws281x/pwm.c external/rpi_ws281x/dma.c
+		external/rpi_ws281x/rpihw.c)
+endif(ENABLE_WS281XPWM)
+
 if(ENABLE_PROTOBUF)
 	set(BUILD_SHARED_LIBS OFF CACHE BOOL "Build shared protobuf library")
 	add_subdirectory(external/protobuf)

dependencies/external/rpi_ws281x

@@ -0,0 +1 @@
+Subproject commit 34c917e25044a7aca4f6dc9326c48c1474b8f28c

libsrc/leddevice/CMakeLists.txt

@@ -97,6 +97,18 @@ SET(Leddevice_SOURCES
 )
 endif(ENABLE_WS2812BPWM)
 
+if(ENABLE_WS281XPWM)
+include_directories(../../dependencies/external/rpi_ws281x)
+SET(Leddevice_HEADERS
+		${Leddevice_HEADERS}
+		${CURRENT_SOURCE_DIR}/LedDeviceWS281x.h
+	)
+SET(Leddevice_SOURCES
+		${Leddevice_SOURCES}
+		${CURRENT_SOURCE_DIR}/LedDeviceWS281x.cpp
+)
+endif(ENABLE_WS281XPWM)
+
 if(ENABLE_TINKERFORGE)
 	SET(Leddevice_HEADERS
 			${Leddevice_HEADERS}
@@ -138,6 +150,10 @@ if(ENABLE_TINKERFORGE)
 	target_link_libraries(leddevice tinkerforge)
 endif()
 
+if(ENABLE_WS281XPWM)
+	target_link_libraries(leddevice ws281x)
+endif()
+
 if(APPLE)
 	target_link_libraries(leddevice hidapi-mac)
 else()

libsrc/leddevice/LedDeviceFactory.cpp

@@ -42,6 +42,10 @@
 	#include "LedDeviceWS2812b.h"
 #endif
 
+#ifdef ENABLE_WS281XPWM
+	#include "LedDeviceWS281x.h"
+#endif
+
 LedDevice * LedDeviceFactory::construct(const Json::Value & deviceConfig)
 {
 	std::cout << "Device configuration: " << deviceConfig << std::endl;
@@ -285,6 +289,18 @@ LedDevice * LedDeviceFactory::construct(const Json::Value & deviceConfig)
 		LedDeviceWS2812b * ledDeviceWS2812b = new LedDeviceWS2812b();
 		device = ledDeviceWS2812b;
 	}
+#endif
+#ifdef ENABLE_WS281XPWM
+	else if (type == "ws281x")
+	{
+		const int gpio = deviceConfig.get("gpio", 18).asInt();
+		const int leds = deviceConfig.get("leds", 12).asInt();
+		const uint32_t freq = deviceConfig.get("freq", (Json::UInt)800000ul).asInt();
+		const int dmanum = deviceConfig.get("dmanum", 5).asInt();
+
+		LedDeviceWS281x * ledDeviceWS281x = new LedDeviceWS281x(gpio, leds, freq, dmanum);
+		device = ledDeviceWS281x;
+	}
 #endif
 	else
 	{

libsrc/leddevice/LedDeviceWS281x.cpp

@@ -0,0 +1,78 @@
+#include <iostream>
+
+#include "LedDeviceWS281x.h"
+
+// Constructor
+LedDeviceWS281x::LedDeviceWS281x(const int gpio, const int leds, const uint32_t freq, const int dmanum)
+{
+	initialized = false;
+	led_string.freq = freq;
+	led_string.dmanum = dmanum;
+	led_string.channel[0].gpionum = gpio;
+	led_string.channel[0].invert = 0;
+	led_string.channel[0].count = leds;
+	led_string.channel[0].brightness = 255;
+	led_string.channel[0].strip_type = WS2811_STRIP_RGB;
+
+	led_string.channel[1].gpionum = 0;
+	led_string.channel[1].invert = 0;
+	led_string.channel[1].count = 0;
+	led_string.channel[1].brightness = 0;
+	led_string.channel[0].strip_type = WS2811_STRIP_RGB;
+	if (ws2811_init(&led_string) < 0) {
+		std::cout << "Unable to initialize ws281x library." << std::endl;
+		throw -1;
+	}
+	initialized = true;
+}
+
+// Send new values down the LED chain
+int LedDeviceWS281x::write(const std::vector<ColorRgb> &ledValues)
+{
+	if (!initialized)
+		return -1;
+
+	int idx = 0;
+	for (const ColorRgb& color : ledValues)
+	{
+		if (idx >= led_string.channel[0].count)
+			break;
+		led_string.channel[0].leds[idx++] = ((uint32_t)color.red << 16) + ((uint32_t)color.green << 8) + color.blue;
+	}
+	while (idx < led_string.channel[0].count)
+		led_string.channel[0].leds[idx++] = 0;
+
+	if (ws2811_render(&led_string))
+		return -1;
+
+	return 0;
+}
+
+// Turn off the LEDs by sending 000000's
+// TODO Allow optional power switch out another gpio, if this code handles it can
+// make it more likely we don't accidentally drive data into an off strip
+int LedDeviceWS281x::switchOff()
+{
+	if (!initialized)
+		return -1;
+
+	int idx = 0;
+	while (idx < led_string.channel[0].count)
+		led_string.channel[0].leds[idx++] = 0;
+
+	if (ws2811_render(&led_string))
+		return -1;
+
+	return 0;
+}
+
+// Destructor
+LedDeviceWS281x::~LedDeviceWS281x()
+{
+	if (initialized)
+	{
+		std::cout << "Shutdown WS281x PWM and DMA channel" << std::endl;
+		ws2811_fini(&led_string);
+	}
+	initialized = false;
+}

libsrc/leddevice/LedDeviceWS281x.h

@@ -0,0 +1,43 @@
+#ifndef LEDDEVICEWS281X_H_
+#define LEDDEVICEWS281X_H_
+
+#pragma once
+
+#include <leddevice/LedDevice.h>
+#include <ws2811.h>
+
+class LedDeviceWS281x : public LedDevice
+{
+public:
+	///
+	/// Constructs the LedDevice for WS281x (one wire 800kHz)
+	///
+	/// @param gpio   The gpio pin to use (BCM chip counting, default is 18)
+	/// @param leds   The number of leds attached to the gpio pin
+	/// @param freq   The target frequency for the data line, default is 800000
+	/// @param dmanum The DMA channel to use, default is 5
+	///
+	LedDeviceWS281x(const int gpio, const int leds, const uint32_t freq, int dmanum);
+
+	///
+	/// Destructor of the LedDevice, waits for DMA to complete and then cleans up
+	///
+	~LedDeviceWS281x();
+
+	///
+	/// Writes the led color values to the led-device
+	///
+	/// @param ledValues The color-value per led
+	/// @return Zero on succes else negative
+	///
+	virtual int write(const std::vector<ColorRgb> &ledValues);
+
+	/// Switch the leds off
+	virtual int switchOff();
+
+private:
+	ws2811_t led_string;
+	bool initialized;
+};
+
+#endif /* LEDDEVICEWS281X_H_ */