tq2440附带的ov9650驱动ov9650.c和测试程序camera.c是按v4l2标准写的吗？

xmkk · 发表于 2013-12-30 10:38:29

论坛上版主说是的，但是我看过测试程序和驱动源码后，觉得并不是那样，求大神详细解释一下，初学驱动编程，求指导！谢谢！！！
camera.c

/*
* TQ2440 camera test program
*
* preview : 320x240 overlay on 320x240 16bpp LCD
*
* TFT LCD size : 320x240
*/
#include <sys/time.h>
#include <sys/types.h>
#include <asm/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/mman.h>
#include <errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include "videodev.h"
#include "videodev2.h"
#include <linux/fb.h>
#define PIXFMT_NUM 5
#define INPUT_NUM 5
#define CTRL_NUM 100
#define V4L2_DEV_NODE "/dev/camera"
#define FB_DEV_NODE "/dev/fb/0"
//typedef struct v4l2_input V_INPUT;
//typedef struct v4l2_format V_FORMAT;
//typedef struct v4l2_fmtdesc V_FMTDESC;
//typedef struct v4l2_queryctrl V_QRYCTRL;
typedef struct fb_var_screeninfo F_VINFO;
unsigned int x_lcd_size, y_lcd_size;
static void v4l2_show_on_fb(int fd, char *fbmem, int frames)
{
int i;
int ret;
char preview_buf[240*320*2]; // 2 byte per pixe
while(1) {
if ((ret = read (fd, &preview_buf, 240*320*2)) < 0) {
perror("read");
return;
}
#if 1 //for 320*240,640*480,800*480
{
int y;
for (y = 0; y < 240; y++)
memcpy(fbmem + x_lcd_size*2*y, preview_buf + 320*2*y, 320*2); //memcpy(dest,src,n)
}
#else //for 240*320
memcpy(fbmem, &preview_buf, 240*320*2);
#endif
fflush(stdout);
}
printf("\n");
}
static unsigned int fb_grab(int fd, char **fbmem)
{
F_VINFO modeinfo;
unsigned int length;
/*get the variable screen information*/
if (ioctl(fd, FBIOGET_VSCREENINFO, &modeinfo) < 0) {
perror("FBIOGET_VSCREENINFO");
exit (EXIT_FAILURE);
}
length = modeinfo.xres * modeinfo.yres * (modeinfo.bits_per_pixel >> 3);
x_lcd_size=modeinfo.xres; //width of tft lcd
y_lcd_size=modeinfo.yres; //height of tft lcd
printf("fb memory info=xres (%d) x yres (%d), %d bpp\n",
modeinfo.xres, modeinfo.yres, modeinfo.bits_per_pixel);
*fbmem = mmap(0, length, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
if (*fbmem < 0) {
perror("mmap()");
length = 0;
}
return length;
}
static void fb_ungrab(char **fbmem, unsigned int length)
{
if (*fbmem)
munmap(*fbmem, length);
}
int main(int argc, char *argv[])
{
int v4l2_fd = -1;
int fb_fd = -1;
char *fbmem = NULL;
unsigned int fb_length = 0;
int preview_frames = 180;
int tmp;
printf("TQ2440 Camera Test Program, Start !\n");
if (argc > 1) {
if (sscanf(argv[1], "%d", &tmp) == 1)
preview_frames = tmp;
}
v4l2_fd = open(V4L2_DEV_NODE, O_RDWR);
if (v4l2_fd < 0) {
perror(V4L2_DEV_NODE);
goto out;
}
fb_fd = open(FB_DEV_NODE, O_RDWR);
if (fb_fd < 0) {
perror(FB_DEV_NODE);
goto out;
}
fflush(stdout); //refresh the screen
if ((fb_length = fb_grab(fb_fd, &fbmem)) == 0)
goto out;
memset(fbmem, 0, fb_length);
printf("Press Ctrl+C to stop !\n");
fflush(stdout);
v4l2_show_on_fb(v4l2_fd, fbmem, preview_frames);
printf("\n");
out:
if (v4l2_fd > 0)
close(v4l2_fd);
fb_ungrab(&fbmem, fb_length);
return 0;
}