Refactored to sk6812; Added white channel

CMakeLists.txt

@@ -13,12 +13,12 @@ set(sources
 	src/main.c
 	src/udpproto.c
 	src/utils.c
-	src/ws2801.c
+	src/sk6812.c
 	src/fader.h
 	src/logger.h
 	src/udpproto.h
 	src/utils.h
-	src/ws2801.h
+	src/sk6812.h
 	)
 
 include_directories(

src/fader.c

@@ -2,7 +2,7 @@
 
 #include "logger.h"
 #include "utils.h"
-#include "ws2801.h"
+#include "sk6812.h"
 
 #include "fader.h"
 
@@ -11,18 +11,20 @@ uint32_t numModules;
 float fadestep = 1;
 double nextFrame;
 
-int somethingChanged = 0; // indicates when a ws2801 update is required
+int somethingChanged = 0; // indicates when a sk6812 update is required
 
 static const double interval = 0.01f;
 
 struct Colour {
-	float red, green, blue; // value range is 0.0 to 255.0
+	float red, green, blue, white; // value range is 0.0 to 255.0
 };
 
 struct Colour *curColour;
 struct Colour *targetColour;
 
-int fader_init(uint32_t nMod)
+struct sk6812_ctx *ledCtx; // global context for the one strip we control
+
+int fader_init(uint32_t nMod, struct sk6812_ctx *ctx)
 {
 	numModules = nMod;
 
@@ -42,8 +44,12 @@ int fader_init(uint32_t nMod)
 		curColour[i].red   = targetColour[i].red   = 0;
 		curColour[i].green = targetColour[i].green = 0;
 		curColour[i].blue  = targetColour[i].blue  = 0;
+		curColour[i].white = targetColour[i].white = 0;
 	}
 
+	// store LED context (initalized externally)
+	ledCtx = ctx;
+
 	// timestamp for the first frame
 	nextFrame = get_hires_time() + interval;
 
@@ -56,39 +62,37 @@ void fader_shutdown(void)
 	free(targetColour);
 }
 
-void fader_set_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b)
+void fader_set_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b, uint8_t w)
 {
 	curColour[module].red   = targetColour[module].red   = r;
 	curColour[module].green = targetColour[module].green = g;
 	curColour[module].blue  = targetColour[module].blue  = b;
+	curColour[module].white = targetColour[module].white = w;
 
 	somethingChanged = 1;
 }
 
-void fader_fade_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b)
+void fader_fade_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b, uint8_t w)
 {
 	targetColour[module].red   = r;
 	targetColour[module].green = g;
 	targetColour[module].blue  = b;
+	targetColour[module].white = w;
 }
 
-void fader_add_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b)
+void fader_add_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b, uint8_t w)
 {
 	curColour[module].red   += r;
 	curColour[module].green += g;
 	curColour[module].blue  += b;
+	curColour[module].white += w;
 
 	if(curColour[module].red > 255) { curColour[module].red = 255; }
 	if(curColour[module].green > 255) { curColour[module].green = 255; }
 	if(curColour[module].blue > 255) { curColour[module].blue = 255; }
+	if(curColour[module].white > 255) { curColour[module].white = 255; }
 
-	targetColour[module].red   += r;
+	targetColour[module] = curColour[module];
-	targetColour[module].green += g;
-	targetColour[module].blue  += b;
-
-	if(targetColour[module].red > 255) { targetColour[module].red = 255; }
-	if(targetColour[module].green > 255) { targetColour[module].green = 255; }
-	if(targetColour[module].blue > 255) { targetColour[module].blue = 255; }
 
 	somethingChanged = 1;
 }
@@ -137,15 +141,17 @@ void fader_update(void)
 		fade_colour(&(curColour[i].red), &(targetColour[i].red), &somethingChanged);
 		fade_colour(&(curColour[i].green), &(targetColour[i].green), &somethingChanged);
 		fade_colour(&(curColour[i].blue), &(targetColour[i].blue), &somethingChanged);
+		fade_colour(&(curColour[i].white), &(targetColour[i].white), &somethingChanged);
 
-		ws2801_set_colour(i,
+		sk6812_set_colour(ledCtx, i,
 				(uint8_t)curColour[i].red,
 				(uint8_t)curColour[i].green,
-				(uint8_t)curColour[i].blue);
+				(uint8_t)curColour[i].blue,
+				(uint8_t)curColour[i].white);
 	}
 
 	if(somethingChanged) {
-		ws2801_send_update();
+		sk6812_send_update(ledCtx);
 		somethingChanged = 0;
 	}
 }

src/fader.h

@@ -3,11 +3,13 @@
 
 #include <stdint.h>
 
-int  fader_init(uint32_t nMod);
+struct sk6812_ctx;
+
+int fader_init(uint32_t nMod, struct sk6812_ctx *ctx);
 void fader_shutdown(void);
-void fader_set_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b);
+void fader_set_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b, uint8_t w);
-void fader_fade_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b);
+void fader_fade_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b, uint8_t w);
-void fader_add_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b);
+void fader_add_colour(uint32_t module, uint8_t r, uint8_t g, uint8_t b, uint8_t w);
 void fader_set_fadestep(uint8_t newFadestep);
 void fader_update(void);
 void fader_wait_frame(void);

src/main.c

@@ -5,7 +5,7 @@
 #include <errno.h>
 #include <stdint.h>
 
-#include "ws2801.h"
+#include "sk6812.h"
 #include "logger.h"
 #include "fader.h"
 #include "udpproto.h"
@@ -13,9 +13,13 @@
 #define PORT 2703
 
 #define NUM_MODULES 160
+#define GPIO_IDX    960
+#define BASE_ADDR   ((void*)0x40000000U)
 
 int main(void)
 {
+	struct sk6812_ctx ctx;
+
 	// initialize logger	
 	logger_init();
 
@@ -26,13 +30,13 @@ int main(void)
 	}
 
 	// initialize ws2801 library
-	if(ws2801_init(NUM_MODULES) == -1) {
+	if(sk6812_init(&ctx, GPIO_IDX, BASE_ADDR, NUM_MODULES) == -1) {
-		LOG(LVL_FATAL, "Could not initialize WS2801 library.");
+		LOG(LVL_FATAL, "Could not initialize SK6812 library.");
 		return 1;
 	}
 
 	// initialise the LED fader
-	if(fader_init(NUM_MODULES) == -1) {
+	if(fader_init(NUM_MODULES, &ctx) == -1) {
 		LOG(LVL_FATAL, "Could not initialize the LED fader.");
 		return 1;
 	}
@@ -47,7 +51,7 @@ int main(void)
 
 	// shut down all modules
 	fader_shutdown();
-	ws2801_shutdown();
+	sk6812_shutdown(&ctx);
 	udpproto_shutdown();
 
 	return 0;

src/sk6812.c

@@ -0,0 +1,45 @@
+#include <time.h>
+#include <string.h>
+#include <malloc.h>
+#include <errno.h>
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <linux/spi/spidev.h>
+
+#include "logger.h"
+#include "sk6812.h"
+
+int sk6812_init(struct sk6812_ctx *ctx, uint32_t gpio_idx, void *phys_baseptr, uint32_t num_modules)
+{
+	// TODO:
+	// - map memory
+	// - setup GPIO
+
+	return 0;
+}
+
+void sk6812_shutdown(struct sk6812_ctx *ctx)
+{
+	// TODO:
+	// - unmap memory
+}
+
+void sk6812_set_colour(struct sk6812_ctx *ctx, uint32_t module, uint8_t red, uint8_t green, uint8_t blue, uint8_t white)
+{
+	uint32_t value =
+		((uint32_t)red << 24U) |
+		((uint32_t)green << 16U) |
+		((uint32_t)blue << 8U) |
+		(uint32_t)white;
+
+	ctx->memptr->led_data[module] = value;
+}
+
+void sk6812_send_update(struct sk6812_ctx *ctx)
+{
+	// TODO: generate rising edge on GPIO
+}
+

src/sk6812.h

@@ -0,0 +1,23 @@
+#ifndef SK6812_H
+#define SK6812_H
+
+#include <stdint.h>
+
+struct sk6812_memory
+{
+	uint32_t num_leds;
+	uint32_t led_data[];
+};
+
+struct sk6812_ctx
+{
+	struct sk6812_memory *memptr;
+	char *gpio_value_path;
+};
+
+int sk6812_init(struct sk6812_ctx *ctx, uint32_t gpio_idx, void *phys_baseptr, uint32_t num_modules);
+void sk6812_shutdown(struct sk6812_ctx *ctx);
+void sk6812_set_colour(struct sk6812_ctx *ctx, uint32_t module, uint8_t red, uint8_t green, uint8_t blue, uint8_t white);
+void sk6812_send_update(struct sk6812_ctx *ctx);
+
+#endif // SK6812_H

src/udpproto.c

@@ -50,7 +50,7 @@ int udpproto_process(void)
 	uint8_t pkgbuf[65536];
 	ssize_t rcvbytes, offset = 0;
 
-	uint8_t r, g, b, action, module;
+	uint8_t r, g, b, w, action, module;
 	int fds_ready;
 
 	// check if there is data to be read (to prevent blocking)
@@ -81,25 +81,26 @@ int udpproto_process(void)
 
 	// parse commands from packet
 	offset = 0;
-	while(offset <= rcvbytes - 4) {
+	while(offset <= rcvbytes - 5) {
 		action = pkgbuf[offset + 0];
 		module = pkgbuf[offset + 1];
 		r      = pkgbuf[offset + 2];
 		g      = pkgbuf[offset + 3];
 		b      = pkgbuf[offset + 4];
+		w      = pkgbuf[offset + 5];
 		offset += 5;
 
 		switch(action) {
 			case SET_COLOUR:
-				fader_set_colour(module, r, g, b);
+				fader_set_colour(module, r, g, b, w);
 				break;
 
 			case FADE_COLOUR:
-				fader_fade_colour(module, r, g, b);
+				fader_fade_colour(module, r, g, b, w);
 				break;
 
 			case ADD_COLOUR:
-				fader_add_colour(module, r, g, b);
+				fader_add_colour(module, r, g, b, w);
 				break;
 
 			case SET_FADESTEP:
@@ -111,7 +112,7 @@ int udpproto_process(void)
 		}
 	}
 
-	return rcvbytes / 5; // number of commands in packet
+	return rcvbytes / 6; // number of commands in packet
 }
 
 void udpproto_shutdown(void)

src/ws2801.c

@@ -1,107 +0,0 @@
-#include <time.h>
-#include <string.h>
-#include <malloc.h>
-#include <errno.h>
-
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <sys/types.h>
-#include <linux/spi/spidev.h>
-
-//#include <wiringPi.h>
-
-#include "logger.h"
-#include "ws2801.h"
-
-static const char    *spi_dev   = "/dev/spidev0.0";
-static const uint32_t spi_speed = 1000000; // clock freq in Hz
-static const uint16_t spi_delay = 0; // us
-static const uint8_t  spi_bits  = 8; // bits per word
-
-uint32_t  numModules;
-uint8_t *message;
-
-int spi_fd = 0;
-
-void send_message(void)
-{
-	struct spi_ioc_transfer tr = {
-		.tx_buf = (unsigned long)message,
-		.rx_buf = (unsigned long)NULL,
-		.len = 3 * numModules,
-		.delay_usecs = spi_delay,
-		.speed_hz = spi_speed,
-		.bits_per_word = 8
-	};
-
-	if(ioctl(spi_fd, SPI_IOC_MESSAGE(1), &tr) < 0) {
-		LOG(LVL_ERR, "ws2801: could not send SPI message: %s", strerror(errno));
-	}
-}
-
-int ws2801_init(uint32_t nMod)
-{
-	// Initialize SPI
-	// We need to have stable data at falling edge of the spi interface (this
-	// means rising edge at the led strip, as the signal is inverted.
-	uint8_t spi_mode = SPI_NO_CS; // | SPI_CPOL;
-
-	spi_fd = open(spi_dev, O_RDWR);
-	if(spi_fd < 0) {
-		LOG(LVL_ERR, "ws2801: cannot open %s: %s", spi_dev, strerror(errno));
-		return -1;
-	}
-
-	if(ioctl(spi_fd, SPI_IOC_WR_MODE, &spi_mode) == -1) {
-		LOG(LVL_ERR, "ws2801: cannot change SPI mode: %s", strerror(errno));
-		return -1;
-	}
-
-	if(ioctl(spi_fd, SPI_IOC_WR_BITS_PER_WORD, &spi_bits) == -1) {
-		LOG(LVL_ERR, "ws2801: cannot change SPI bits per word: %s", strerror(errno));
-		return -1;
-	}
-
-	if(ioctl(spi_fd, SPI_IOC_WR_MAX_SPEED_HZ, &spi_speed) == -1) {
-		LOG(LVL_ERR, "ws2801: cannot change SPI speed: %s", strerror(errno));
-		return -1;
-	}
-
-	// create the message array
-	numModules = nMod;
-	message = malloc(3 * nMod * sizeof(uint8_t));
-
-	if(!message) {
-		LOG(LVL_ERR, "ws2801: could not allocate the message array!");
-		return -1;
-	}
-
-	return 0;
-}
-
-void ws2801_shutdown(void)
-{
-	close(spi_fd);
-
-	if(message != NULL) { free(message); message = NULL; }
-}
-
-void ws2801_set_colour(uint32_t module, uint8_t red, uint8_t green, uint8_t blue)
-{
-	//message[3*module + 0] = ~red;
-	//message[3*module + 1] = ~green;
-	//message[3*module + 2] = ~blue;
-	message[3*module + 0] = red;
-	message[3*module + 1] = blue;
-	message[3*module + 2] = green;
-}
-
-void ws2801_send_update(void)
-{
-	send_message();
-
-	static const struct timespec sleepval = {0, 550000};
-	nanosleep(&sleepval, NULL);
-}
-

src/ws2801.h

@@ -1,11 +0,0 @@
-#ifndef WS2801_H
-#define WS2801_H
-
-#include <stdint.h>
-
-int ws2801_init(uint32_t num_modules);
-void ws2801_shutdown(void);
-void ws2801_set_colour(uint32_t module, uint8_t red, uint8_t green, uint8_t blue);
-void ws2801_send_update(void);
-
-#endif // WS2801_H