电子量产工具——2-3显示系统_显示管理

文章目录

电子量产工具——2-3显示系统_显示管理
软件总框架
一、显示管理
二、
总结

软件总框架

在这里插入图片描述

一、显示管理

在这里插入图片描述

disp_manager.c的作用

1.承上启下
2.下面各个模块把DispOpr注册进来
3.上面选择某个模块
4.还提供一些函数，比如PutPixel

二、

1.framebuffer.c

framebuffer.c

#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <linux/fb.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>

#include "disp_manager.h"

static int fd_fb;
static struct fb_var_screeninfo var;	/* Current var */
static int screen_size;
static unsigned char *fb_base;
static unsigned int line_width;
static unsigned int pixel_width;

static int FbDeviceInit(void)
{
	fd_fb = open("/dev/fb0", O_RDWR);
	if (fd_fb < 0)
	{
		printf("can't open /dev/fb0\n");
		return -1;
	}
	if (ioctl(fd_fb, FBIOGET_VSCREENINFO, &var))
	{
		printf("can't get var\n");
		return -1;
	}

	line_width  = var.xres * var.bits_per_pixel / 8;
	pixel_width = var.bits_per_pixel / 8;
	screen_size = var.xres * var.yres * var.bits_per_pixel / 8;
	fb_base = (unsigned char *)mmap(NULL , screen_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_fb, 0);
	if (fb_base == (unsigned char *)-1)
	{
		printf("can't mmap\n");
		return -1;
	}

	return 0;
}

static int FbDeviceExit(void)
{
	munmap(fb_base, screen_size);
	close(fb_base);
	return 0;
}

/* 可以返回LCD的framebuffer, 以后上层APP可以直接操作LCD, 可以不用 FbFlushRegion
 * 也可以malloc返回一块无关的buffer, 要使用 FbFlushRegion
 *
 */
static int FbGetBuffer(PDispBuff ptDispBuff)
{
	ptDispBuff->iXres = var.xres;
	ptDispBuff->iYres = var.yres;
	ptDispBuff->iBpp  = var.bits_per_pixel;
	ptDispBuff->buff  = fb_base;

	return 0;
}
static int FbFlushRegion(PRegion ptRegion, PDispBuff ptDispBuff)
{

	return 0;
}

static DispOpr g_tFramebufferOpr = {
	.name 		  = "fb",
	.DeviceInit   = FbDeviceInit,
	.DeviceExit   = FbDeviceExit,
	.GetBuffer    = FbGetBuffer,
	.FlushRegion  = FbFlushRegion,
};

//3.注册LCD硬件相关的结构体
void FramebufferInit(void)
{
	RegisterDisplay(&g_tFramebufferOpr);
}

2.disp_manager.h

disp_manager.h

#ifndef _DISP_MANAGER_H
#define _DISP_MANAGER_H

typedef struct DispBuff {
	int iXres;
	int iYres;
	int iBpp;
	char *buff;
}DispBuff, *PDispBuff;

typedef struct Region {
	int iLeftUpX;
	int iLeftUpY;
	int iWidth;
	int iHeigh;
}Region, *PRegion;

typedef struct DispOpr {
	char *name;
	int DeviceInit(void);
	int DeviceExit(void);
	int GetBuffer(PDispBuff ptDispBuff);
	int FlushRegion(PRegion ptRegion, char *buffer);
	struct DispOpr *ptNext;
}DispOpr, *PDispOpr;

void RegisterDisplay(PDispOpr ptDispOpr);
void SelectDefaultDisplay(char *name);
int InitDefaultDisplay(void);
void DisplayInit(PDispOpr ptDispOpr);
int PutPixel(int x, int y, unsigned int dwColor);
static int FlushDisplayRegion(PRegion ptRegion, PDispBuff ptDispBuff);


#endif

3.disp_manager.c

disp_manager.c

#include "disp_manager.h"

/* 管理底层的LCD、WEB */
static PDispOpr g_DispDevs = NULL; //5.对应不同的显示方式 ——》SelectDefaultDisplay
static PDispOpr g_DispDefault = NULL;
static DispBuff g_tDispBuff;
static int line_width;
static int pixel_width;



//dwColor double word  
//8.绘制想要的图片  ————》》 更新到硬件上去FlushDisplayRegion
int PutPixel(int x, int y, unsigned int dwColor)
{
	unsigned char *pen_8 = g_tDispBuff->buff+y*line_width+x*pixel_width;
	unsigned short *pen_16;	
	unsigned int *pen_32;	

	unsigned int red, green, blue;	

	pen_16 = (unsigned short *)pen_8;
	pen_32 = (unsigned int *)pen_8;

	switch (g_tDispBuff.iBpp)
	{
		case 8:
		{
			*pen_8 = dwColor;
			break;
		}
		case 16:
		{
			/* 565 */
			red   = (dwColor >> 16) & 0xff;
			green = (dwColor >> 8) & 0xff;
			blue  = (dwColor >> 0) & 0xff;
			dwColor = ((red >> 3) << 11) | ((green >> 2) << 5) | (blue >> 3);
			*pen_16 = dwColor;
			break;
		}
		case 32:
		{
			*pen_32 = dwColor;
			break;
		}
		default:
		{
			printf("can't surport %dbpp\n", g_tDispBuff.iBpp);
			break;
		}
	}
}

//4.注册LCD硬件相关函数 放入 g_DispDevs 链表
void RegisterDisplay(PDispOpr ptDispOpr)
{
	ptDispOpr->ptNext = g_DispDevs;
	g_DispDevs = ptDispOpr;
	
}

//6.来选择默认的输出设备
void SelectDefaultDisplay(char *name)
{
	PDispOpr pTmp = g_DispDevs;
	while (pTmp)
	{
		if(strcmp(name, pTmp->name) == 0)
		{
			g_DispDefault = pTmp;
			return 0;
		}

		pTmp = pTmp->ptNext;
	}
	return -1;
}

//7.来初始化默认的设备     ————》》然后去调用///        PutPixel
int InitDefaultDisplay(void)
{
	int ret;

	ret = g_DispDefault->DeviceInit(); //先初始化硬件
	if(ret)
	{
		printf("DeviceInit err\n");
		return -1;
	}

	ret = g_DispDefault->GetBuffer(g_tDispBuff); //获得一个buffer
	if(ret)
	{
		printf("GetBuffer err\n");
		return -1;
	}

	line_width  = g_tDispBuff.iXres * g_tDispBuff.iBpp/8;
	pixel_width = g_tDispBuff.iBpp/8
	
	return 0;
}

//9.绘制好的区域 更新(刷)到硬件上去
static int FlushDisplayRegion(PRegion ptRegion, PDispBuff ptDispBuff)
{
	int ret;
	ret = g_DispDefault->FlushRegion(ptRegion, ptDispBuff);
	return 0;
}

//1.display 初始化
void DisplayInit(PDispOpr ptDispOpr)
{
	FramebufferInit(); //2.调用framebuffer初始化
}

总结

1.display 初始化
{//2.调用framebuffer初始化}
3.注册LCD硬件相关的结构体
4.注册LCD硬件相关函数放入 g_DispDevs 链表
5.对应不同的显示方式 ——》SelectDefaultDisplay
6.来选择默认的输出设备
7.来初始化默认的设备 ————》》然后去调用 PutPixel
8.绘制想要的图片 ————》》更新到硬件上去 FlushDisplayRegion
9.绘制好的区域更新(刷)到硬件上去