Merge pull request #2166 from QB4-dev/master

Linux Framebuffer support

csrc/u8g2.h

@@ -1783,6 +1783,10 @@ void u8g2_SetupBuffer_TGA_LCD(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb);
 /* u8x8_d_bitmap.c */
 void u8g2_SetupBitmap(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb, uint16_t pixel_width, uint16_t pixel_height);
 
+/*==========================================*/
+/* u8x8_d_framebuffer.c */
+void u8g2_SetupLinuxFb(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb, const char *fb_device);
+
 
 /*==========================================*/
 /* u8x8_d_utf8.c */

csrc/u8x8.h

@@ -815,6 +815,11 @@ void u8x8_SaveBitmapTGA(u8x8_t *u8x8, const char *filename);
 void u8x8_SetupBitmap(u8x8_t *u8x8, uint16_t pixel_width, uint16_t pixel_height);
 uint8_t u8x8_ConnectBitmapToU8x8(u8x8_t *u8x8);
 
+/*==========================================*/
+/* u8x8_d_framebuffer.c */
+void u8x8_SetupLinuxFb(u8x8_t *u8x8, int fbfd);
+void u8x8_LinuxFbSetActiveColor(uint32_t color);
+
 /*==========================================*/
 /* u8x8_d_utf8.c */
 void u8x8_Setup_Utf8(u8x8_t *u8x8);	/* stdout UTF-8 display */

sys/linux-fb/common/u8x8_d_framebuffer.c

@@ -0,0 +1,277 @@
+/*
+
+  u8x8_framebuffer.c
+  
+  a framebuffer device
+
+*/
+
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <linux/fb.h>
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+#include "u8g2.h"		/* because of u8g2_Setup... */
+
+/*========================================================*/
+/* framebuffer struct */
+
+struct _u8x8_linuxfb_struct
+{
+	u8x8_msg_cb u8x8_bitmap_display_old_cb;
+	int fbfd;
+	struct fb_var_screeninfo vinfo;
+	struct fb_fix_screeninfo finfo;
+	uint8_t *u8x8_buf;
+	uint8_t *u8g2_buf;
+	uint8_t *fbp;
+	uint32_t active_color;
+};
+
+typedef struct _u8x8_linuxfb_struct u8x8_linuxfb_t;
+
+/*========================================================*/
+/* framebuffer functions */
+
+uint8_t u8x8_LinuxFb_alloc(int fbfd, u8x8_linuxfb_t *fb)
+{
+	size_t tile_width;
+	size_t tile_height;
+	size_t screensize = 0;
+
+	// Make sure that the display is on.
+	if (ioctl(fbfd, FBIOBLANK, FB_BLANK_UNBLANK) != 0) {
+		perror("ioctl(FBIOBLANK)");
+		return 0;
+	}
+
+	// Get fixed screen information
+	if (ioctl(fbfd, FBIOGET_FSCREENINFO, &fb->finfo)) {
+		fprintf(stderr,"Error reading fixed information.\n");
+		return 0;
+	}
+
+	// Get variable screen information
+	if (ioctl(fbfd, FBIOGET_VSCREENINFO, &fb->vinfo)) {
+		fprintf(stderr,"Error reading variable information.\n");
+		return 0;
+	}
+
+	if ( fb->u8x8_buf != NULL )
+		free(fb->u8x8_buf);
+
+	fb->fbfd = fbfd;
+	fb->active_color = 0xFFFFFF;
+	tile_width = (fb->vinfo.xres+7)/8;
+	tile_height = (fb->vinfo.yres+7)/8;
+
+	/* allocate the tile buffer twice, one for u8x8 and another bitmap for u8g2 */
+	fb->u8x8_buf = (uint8_t *)malloc(tile_width*tile_height*8*2);
+	fb->u8g2_buf = (uint8_t *)fb->u8x8_buf + tile_width*tile_height*8;
+
+	if ( fb->u8x8_buf == NULL ) {
+		fb->u8g2_buf = NULL;
+		return 0;
+	}
+
+	// Map the device to memory
+	fb->fbp = mmap(0, fb->finfo.smem_len, PROT_READ | PROT_WRITE, MAP_SHARED, fbfd, 0);
+	if (fb->fbp == MAP_FAILED) {
+		printf("Error: failed to map framebuffer device to memory.\n");
+		return 0;
+	}
+	memset(fb->fbp,0x00,screensize);
+	return 1;
+}
+
+void u8x8_LinuxFb_DrawTiles(u8x8_linuxfb_t *fb, uint16_t tx, uint16_t ty, uint8_t tile_cnt, uint8_t *tile_ptr)
+{
+	uint8_t byte;
+	memset(fb->u8x8_buf,0x00,8*tile_cnt);
+
+	for(int i=0; i < tile_cnt * 8; i++){
+		byte = *tile_ptr++;
+		for(int bit=0; bit < 8;bit++){
+			if(byte & (1 << bit))
+				fb->u8x8_buf[tile_cnt*bit+(i/8)] |= (1 << i%8);
+		}
+	}
+
+	switch (fb->vinfo.bits_per_pixel) {
+		case 1:
+			memcpy(fb->fbp+ty*8*tile_cnt, fb->u8x8_buf, tile_cnt*8);
+			break;
+		case 16:{
+			uint16_t pixel;
+			uint16_t *fbp16 = (uint16_t *)fb->fbp;
+			long int location = 0;
+
+			uint8_t b = (fb->active_color & 0x0000FF) >> 0;
+			uint8_t g = (fb->active_color & 0x00FF00) >> 8;
+			uint8_t r = (fb->active_color & 0xFF0000) >> 16;
+
+			for(int y=0; y<8;y++){
+				for(int x=0; x<8*tile_cnt;x++){
+					if(fb->u8x8_buf[(x/8) + (y*tile_cnt) ] & (1 << x%8))
+						pixel =  r<<11 | g << 5 | b;
+					else
+						pixel = 0x000000;
+					location = (x + fb->vinfo.xoffset) + ((ty*8)+y + fb->vinfo.yoffset) * fb->finfo.line_length / 2;
+					memcpy(&fbp16[location], &pixel, sizeof(pixel));
+				}
+			}
+		}break;
+		case 32:{
+			uint32_t pixel;
+			uint32_t *fbp32 = (uint32_t *)fb->fbp;
+			long int location = 0;
+
+			for(int y=0; y<8;y++){
+				for(int x=0; x<8*tile_cnt;x++){
+					if(fb->u8x8_buf[(x/8) + (y*tile_cnt) ] & (1 << x%8))
+						pixel = fb->active_color;
+					else
+						pixel = 0x000000;
+					location = (x + fb->vinfo.xoffset) + ((ty*8)+y + fb->vinfo.yoffset) * fb->finfo.line_length / 4;
+					memcpy(&fbp32[location], &pixel, sizeof(pixel));
+				}
+			}
+		}break;
+		//TODO support 24/16/8 bits_per_pixel
+		default:
+			break;
+	}
+}
+
+/*========================================================*/
+/* global objects for the framebuffer */
+
+static u8x8_linuxfb_t u8x8_linuxfb;
+static u8x8_display_info_t u8x8_libuxfb_info =
+{
+	/* chip_enable_level = */ 0,
+	/* chip_disable_level = */ 1,
+
+	/* post_chip_enable_wait_ns = */ 0,
+	/* pre_chip_disable_wait_ns = */ 0,
+	/* reset_pulse_width_ms = */ 0,
+	/* post_reset_wait_ms = */ 0,
+	/* sda_setup_time_ns = */ 0,
+	/* sck_pulse_width_ns = */ 0,
+	/* sck_clock_hz = */ 4000000UL,
+	/* spi_mode = */ 1,
+	/* i2c_bus_clock_100kHz = */ 0,
+	/* data_setup_time_ns = */ 0,
+	/* write_pulse_width_ns = */ 0,
+	/* tile_width = */ 8,		/* dummy value */
+	/* tile_hight = */ 4,		/* dummy value */
+	/* default_x_offset = */ 0,
+	/* flipmode_x_offset = */ 0,
+	/* pixel_width = */ 64,		/* dummy value */
+	/* pixel_height = */ 32		/* dummy value */
+};
+
+
+/*========================================================*/
+/* functions for handling of the global objects */
+
+/* allocate bitmap */
+/* will be called by u8x8_SetupBitmap or u8g2_SetupBitmap */
+static uint8_t u8x8_SetLinuxFbDevice(U8X8_UNUSED u8x8_t *u8x8, int fbfd)
+{
+	struct fb_var_screeninfo *vinfo = &u8x8_linuxfb.vinfo;
+
+	/* update the global framebuffer object, allocate memory */
+	if ( u8x8_LinuxFb_alloc(fbfd, &u8x8_linuxfb) == 0 )
+		return 0;
+
+	/* update the u8x8 info object */
+	u8x8_libuxfb_info.tile_width = (u8x8_linuxfb.vinfo.xres+7)/8;
+	u8x8_libuxfb_info.tile_height = (vinfo->yres+7)/8;
+	u8x8_libuxfb_info.pixel_width = vinfo->xres;
+	u8x8_libuxfb_info.pixel_height = vinfo->yres;
+	return 1;
+}
+
+/* draw tiles to the bitmap, called by the device procedure */
+static void u8x8_DrawLinuxFbTiles(U8X8_UNUSED u8x8_t *u8x8, uint16_t tx, uint16_t ty, uint8_t tile_cnt, uint8_t *tile_ptr)
+{
+	u8x8_LinuxFb_DrawTiles(&u8x8_linuxfb, tx, ty, tile_cnt, tile_ptr);
+}
+
+/*========================================================*/
+
+static uint8_t u8x8_framebuffer_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr)
+{
+	u8g2_uint_t x, y, c;
+	uint8_t *ptr;
+	switch(msg)
+	{
+	case U8X8_MSG_DISPLAY_SETUP_MEMORY:
+		u8x8_d_helper_display_setup_memory(u8x8, &u8x8_libuxfb_info);
+		break;
+	case U8X8_MSG_DISPLAY_INIT:
+		u8x8_d_helper_display_init(u8x8);	/* update low level interfaces (not required here) */
+		break;
+	case U8X8_MSG_DISPLAY_SET_POWER_SAVE:
+		break;
+	case U8X8_MSG_DISPLAY_SET_FLIP_MODE:
+		break;
+	case U8X8_MSG_DISPLAY_DRAW_TILE:
+		x = ((u8x8_tile_t *)arg_ptr)->x_pos;
+		y = ((u8x8_tile_t *)arg_ptr)->y_pos;
+		c = ((u8x8_tile_t *)arg_ptr)->cnt;
+		ptr = ((u8x8_tile_t *)arg_ptr)->tile_ptr;
+		do
+		{
+			u8x8_DrawLinuxFbTiles(u8x8, x, y, c, ptr);
+			x += c;
+			arg_int--;
+		} while( arg_int > 0 );
+		break;
+	default:
+	  return 0;
+	}
+	return 1;
+}
+
+
+/*========================================================*/
+/* u8x8 and u8g2 setup functions */
+
+void u8x8_SetupLinuxFb(u8x8_t *u8x8, int fbfd)
+{
+	u8x8_SetLinuxFbDevice(u8x8,fbfd);
+
+	/* setup defaults */
+	u8x8_SetupDefaults(u8x8);
+
+	/* setup specific callbacks */
+	u8x8->display_cb = u8x8_framebuffer_cb;
+
+	/* setup display info */
+	u8x8_SetupMemory(u8x8);
+}
+
+void u8g2_SetupLinuxFb(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb, const char *fb_device)
+{
+	int fbfd = open(fb_device,O_RDWR);
+	if (fbfd == -1) {
+		perror(fb_device);
+		return;
+	}
+
+	/* allocate bitmap, assign the device callback to u8x8 */
+	u8x8_SetupLinuxFb(u8g2_GetU8x8(u8g2), fbfd);
+
+	/* configure u8g2 in full buffer mode */
+	u8g2_SetupBuffer(u8g2, u8x8_linuxfb.u8g2_buf, (u8x8_libuxfb_info.pixel_height+7)/8, u8g2_ll_hvline_vertical_top_lsb, u8g2_cb);
+}
+
+void u8x8_LinuxFbSetActiveColor(uint32_t color)
+{
+	u8x8_linuxfb.active_color = color;
+}

sys/linux-fb/hello_world/Makefile

@@ -0,0 +1,12 @@
+CFLAGS = -g -Wall -I../../../csrc/.
+
+SRC = $(shell ls ../../../csrc/*.c) $(shell ls ../common/u8x8_d_framebuffer.c ) main.c
+
+OBJ = $(SRC:.c=.o)
+
+hello_world: $(OBJ)
+	$(CC) $(CFLAGS) $(LDFLAGS) $(OBJ) -o $@
+
+clean:
+	-rm -f $(OBJ) hello_world
+

sys/linux-fb/hello_world/main.c

@@ -0,0 +1,29 @@
+#include "u8g2.h"
+#include <stdio.h>
+
+u8g2_t u8g2;
+
+const char *fb_dev = "/dev/fb0";
+
+int main(int argc, char **argv)
+{
+	if(argc > 1){
+		fb_dev = argv[1];
+	}
+
+	u8g2_SetupLinuxFb(&u8g2,U8G2_R0, fb_dev);
+	u8x8_InitDisplay(u8g2_GetU8x8(&u8g2));
+	u8x8_SetPowerSave(u8g2_GetU8x8(&u8g2), 0);
+	u8g2_SetFont(&u8g2, u8g2_font_helvB08_tr);
+
+	u8g2_ClearBuffer(&u8g2);
+	u8g2_DrawUTF8(&u8g2, 2, 10, "U8G2 on");
+	u8g2_DrawUTF8(&u8g2, 2, 20, "Linux");
+	u8g2_DrawUTF8(&u8g2, 2, 31, "Framebuffer");
+	u8g2_SetFont(&u8g2, u8g2_font_open_iconic_all_4x_t);
+	u8g2_DrawGlyph(&u8g2,90, 32, 120);
+	//u8g2_DrawFrame(&u8g2,0,0,128,32);
+	u8g2_SendBuffer(&u8g2);
+	return 0;
+}
+