fbapi.h

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/*
File name : fbapi.h
	080831
	080906
	BY StevenZ
*/

#ifndef _FBAPI_H_
#define _FBAPI_H_
#include <linux/fb.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <asm/page.h>
#define TRUE        1
#define FALSE       0
#define MAX(x,y)        ((x)>(y)?(x)y))
#define MIN(x,y)        ((x)<(y)?(x)y))

//#define DEBUG
#ifdef DEBUG
#define DPRINTF(x...) printf("debug:"##x)
#else
#define DPRINTF(x...)
#endif

//a framebuffer device structure;
typedef struct fbdev{
       int fb;
       unsigned long fb_mem_offset;
       unsigned long fb_mem;
       struct fb_fix_screeninfo fb_fix;
       struct fb_var_screeninfo fb_var;
       char dev[20];
} FBDEV, *PFBDEV;

//open & init a frame buffer
//to use this function,
//in our arm,
//you must set FBDEV.dev="/dev/fb/0"
//it's your frame buffer.
int fb_open(PFBDEV pFbdev);

//close a frame buffer
int fb_close(PFBDEV pFbdev);

//get display depth
int get_display_depth(PFBDEV pFbdev);

//full screen clear
void fb_memset(void *addr, int c, size_t len);




//open & init a frame buffer
int fb_open(PFBDEV pFbdev)
{
       pFbdev->fb = open(pFbdev->dev, O_RDWR);
       if(pFbdev->fb < 0)
       {
              printf("Error opening %s: %m. Check kernel config\n", pFbdev->dev);
              return FALSE;
       }

       if (-1 == ioctl(pFbdev->fb,FBIOGET_VSCREENINFO,&(pFbdev->fb_var)))
       {
              printf("ioctl FBIOGET_VSCREENINFO\n");
              return FALSE;
       }

       if (-1 == ioctl(pFbdev->fb,FBIOGET_FSCREENINFO,&(pFbdev->fb_fix)))
       {
              printf("ioctl FBIOGET_FSCREENINFO\n");
              return FALSE;
       }

       //map physics address to virtual address
       pFbdev->fb_mem_offset = (unsigned long)(pFbdev->fb_fix.smem_start) & (~PAGE_MASK);
       pFbdev->fb_mem = (unsigned long int)mmap(NULL, pFbdev->fb_fix.smem_len + pFbdev->fb_mem_offset,PROT_READ | PROT_WRITE, MAP_SHARED, pFbdev->fb, 0);

       if (-1L == (long) pFbdev->fb_mem)
       {
              printf("mmap error! mem:%d offset:%d\n", pFbdev->fb_mem, pFbdev->fb_mem_offset);
              return FALSE;
       }
       return TRUE;
}

//close frame buffer
int fb_close(PFBDEV pFbdev)
{
	
       munmap((void *)(pFbdev->fb_mem+pFbdev->fb_mem_offset),pFbdev->fb_fix.smem_len);
       close(pFbdev->fb);
       pFbdev->fb=-1;
}

//get display depth
int get_display_depth(PFBDEV pFbdev)
{
       if(pFbdev->fb<=0)
       {
              printf("fb device not open, open it first\n");
              return FALSE;
       }
       return pFbdev->fb_var.bits_per_pixel;
}

//full screen clear
inline void fb_memset (void *addr, int c, size_t len)
{
    memset(addr, c, len);
}

#endif