Implemented memory mapping

src/sk6812.c

@@ -1,30 +1,53 @@
-#include <time.h>
+#include <sys/types.h>
-#include <string.h>
+#include <sys/stat.h>
-#include <malloc.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/mman.h>
 #include <errno.h>
 
-#include <unistd.h>
+#include <stdlib.h>
-#include <fcntl.h>
+#include <string.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 memory map for LED memory.
-	// - setup GPIO
+	 */
+	size_t mapsize = num_modules*sizeof(uint32_t);
+	size_t pagesize = (size_t)getpagesize();
+
+	if((mapsize % pagesize) != 0) {
+		mapsize = pagesize * (mapsize / pagesize + 1);
+	}
+
+	ctx->devmem_fd = open("/dev/mem", O_RDWR|O_SYNC);
+	if(ctx->devmem_fd == -1) {
+		LOG(LVL_ERR, "sk6812: open(/dev/mem) failed: %s.", strerror(errno));
+		return -1;
+	}
+
+	ctx->memptr = (struct sk6812_memory*)mmap(0, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, ctx->devmem_fd, (off_t)phys_baseptr);
+	if(ctx->memptr == MAP_FAILED) {
+		LOG(LVL_ERR, "sk6812: mmap(0x%08X) failed: %s.", phys_baseptr, strerror(errno));
+		close(ctx->devmem_fd);
+		return -1;
+	}
+
+	ctx->mapped_size = mapsize;
+
+	// write number of modules to mapped memory
+	ctx->memptr->num_leds = num_modules;
 
 	return 0;
 }
 
 void sk6812_shutdown(struct sk6812_ctx *ctx)
 {
-	// TODO:
+	munmap(ctx->memptr, ctx->mapped_size);
-	// - unmap memory
+	close(ctx->devmem_fd);
 }
 
 void sk6812_set_colour(struct sk6812_ctx *ctx, uint32_t module, uint8_t red, uint8_t green, uint8_t blue, uint8_t white)

src/sk6812.h

@@ -13,6 +13,8 @@ struct sk6812_ctx
 {
 	struct sk6812_memory *memptr;
 	char *gpio_value_path;
+	int devmem_fd;
+	size_t mapped_size;
 };
 
 int sk6812_init(struct sk6812_ctx *ctx, uint32_t gpio_idx, void *phys_baseptr, uint32_t num_modules);