SmartPDCode/pro/src/lcd_drv.c

#include "lcd_drv.h"
#include "io.h"
#include "elog.h"
#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>


#define BACKLIGHT_GPIO_NUM 98
static int fd_fb = 0 ;
static struct fb_var_screeninfo var; 
static unsigned char *fb_base;
static unsigned int line_width;
static unsigned int pixel_width;
static int screen_size;

/// @brief 初始化LCD
/// @param  
/// @return 
int lcd_init(void)
{
    //打开背光
    //初始化IO
    io_init(BACKLIGHT_GPIO_NUM);
    //设置输出
    io_set_dir(BACKLIGHT_GPIO_NUM,1);
    //拉高
    io_set_value(BACKLIGHT_GPIO_NUM,1);

    fd_fb = open("/dev/fb0", O_RDWR);
    if (fd_fb < 0) {
        log_e("Can't open /dev/fb0\n");
        return -1;
    }

    if(ioctl(fd_fb, FBIOGET_VSCREENINFO, &var)) {
        log_e("Can't get var\n");
        return -1;
    }
    line_width = var.xres * var.bits_per_pixel / 8; // 一行多少byte
    pixel_width = var.bits_per_pixel / 8;           // 一个像素多少byte
    screen_size = var.xres * var.yres * var.bits_per_pixel / 8; // 一屏多少byte

    fb_base = (unsigned char*)mmap(NULL, screen_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_fb, 0);
    if (fb_base == (unsigned char*)MAP_FAILED) {
        log_e("Can't mmap\n");
        return -1;
    }
    //清屏为黑色 0x00 黑色 0xFF 白色
    memset(fb_base, 0x00, screen_size);

    return 0;
}

/// @brief 释放LCD接口
/// @param  
/// @return 
int lcd_deinit(void)
{
	munmap(fb_base , screen_size);
	close(fd_fb);
    io_set_dir(BACKLIGHT_GPIO_NUM,0);
    io_set_value(BACKLIGHT_GPIO_NUM,0);
    io_deinit(BACKLIGHT_GPIO_NUM);

	return 0;
}

/// @brief 画点
/// @param x 
/// @param y 
/// @param color 
void lcd_put_pixel(int x, int y, unsigned int color)
{
    unsigned char *pen_8 = fb_base + 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(var.bits_per_pixel) { /* bpp 像素深度 */
        case 8:
        {
            *pen_8 = color;
            break;
        }
        case 16:
        {
            /* RGB565 */
            red = (color >> 16) & 0xFF;
            green = (color >> 8) & 0xFF;
            blue = (color >> 0) & 0xFF;
            color = ((red >> 3) << 11) | ((green >> 2) << 5) | (blue >> 3);
            *pen_16 = color;
            break;
        }
        case 32:
        {
            /* RGB888 */
            *pen_32 = color;
            break;
        }
        default:
        {
            log_e("Can't support %d bpp\n", var.bits_per_pixel);
            break;
        }
    }
}

#if 0
/// @brief 绘制字符 在LCD指定位置上显示一个8*16的字符
/// @param x 
/// @param y 
/// @param c 
/// @param color 
void lcd_put_ascii(int x, int y, unsigned char c, int color)
{
	unsigned char *dots = (unsigned char *)&fontdata_8x16[c*16];
	int i, b;
	unsigned char byte;

	for (i = 0; i < 16; i++)
	{
		byte = dots[i];
		for (b = 7; b >= 0; b--)
		{
			if (byte & (1<<b))
			{
				/* show */
				lcd_put_pixel(x+7-b, y+i, color); /* 白 */
			}
			else
			{
				/* hide */
				lcd_put_pixel(x+7-b, y+i, 0); /* 黑 */
			}
		}
	}
}


/// @brief 在指定位置显示字符串
/// @param x 
/// @param y 
/// @param string 
/// @param color 
void lcd_show_string(int x, int y, unsigned char *string, int color)
{
	int string_len = strlen(string);
	int string_x = x;
	int string_y = y;


	for(int i = 0; i < string_len; i++)
	{
		if(string[i] == '\n')
		{
			string_y += 18;
			string_x = 0;
			if(string_y > var.yres)
			{
				return ;
			}
		}
		else
		{
			lcd_put_ascii(string_x, string_y, string[i], color);
			string_x += 8;
			if(string_x > var.xres)
			{
				string_x = 0;
				string_y += 18;
				if(string_y > var.yres)
				{
					return ;
				}
			}
		}
		
	}
}

/// @brief 显示中文
/// @param x 
/// @param y 
/// @param str 
/// @param color 
void lcd_put_chinese(int x, int y, unsigned char *str, unsigned int color)
{
	unsigned int area  = str[0] - 0xA1;
	unsigned int where = str[1] - 0xA1;
	unsigned char *dots = hzkmem + (area * 94 + where)*32;
	unsigned char byte;

	int i, j, b;
	for (i = 0; i < 16; i++)
		for (j = 0; j < 2; j++)
		{
			byte = dots[i*2 + j];
			for (b = 7; b >=0; b--)
			{
				if (byte & (1<<b))
				{
					/* show */
					lcd_put_pixel(x+j*8+7-b, y+i, color); /* 白 */
				}
				else
				{
					/* hide */
					lcd_put_pixel(x+j*8+7-b, y+i, 0); /* 黑 */
				}	
			}
		}
}

#endif