struct dm_info *dm = (struct dm_info *) arg;
	static unsigned long local_count=0;
        ++local_count;
        //if (local_count % 2)
          //    return IRQ_HANDLED;
	++dm->vsync_cnt;
	wake_up_interruptible(&dm->vsync_wait);
	return IRQ_HANDLED;
} /* Wait for a vsync interrupt.  This routine sleeps so it can only be called * from process context. */static int dm64xxfb_wait_for_vsync(struct dm_win_info *w){	struct dm_info *dm = w->dm;	wait_queue_t wq;	unsigned long cnt;	int ret;		DBGENTER;	init_waitqueue_entry(&wq, current);	cnt = dm->vsync_cnt;	ret = wait_event_interruptible_timeout(dm->vsync_wait,		cnt != dm->vsync_cnt, dm->timeout);	if (ret < 0)		RETURN(ret);	if (ret == 0)		RETURN(-ETIMEDOUT);	RETURN(0);}/* Sets a uniform attribute value over a rectangular area on the attribute  * window. The attribute value (0 to 7) is passed through the fb_fillrect's  * color parameter. */static int dm64xxfb_set_attr_blend(struct fb_fillrect *r){	struct fb_info *info = &dm.osd1->info;	struct fb_var_screeninfo *var = &dm.osd1->info.var;	unsigned long start = 0;	u8 blend;	u32 width_bytes;		if (r->dx + r->width > var->xres_virtual) 		return -EINVAL;	if (r->dy + r->height > var->yres_virtual) 		return -EINVAL;	if (r->color < 0 || r->color > 7)		return -EINVAL;			/* since bits_per_pixel = 4, this will truncate the width if it is 	 * not even. Similarly r->dx will be rounded down to an even pixel.	 * ... Do we want to return an error otherwise?	 */ 		width_bytes = r->width * var->bits_per_pixel / 8;	start = dm.osd1->fb_base + r->dy * info->fix.line_length 				 + r->dx * var->bits_per_pixel / 8; 		blend = (((u8) r->color & 0xf)<<4) | ((u8) r->color);	while (r->height--) {		start += info->fix.line_length;		memset((void *) start, blend, width_bytes);	}		return 0;}static int dm64xxfb_set_attr_transp(int transp_on){}/* These position parameters are given through fb_var_screeninfo. * xp = var.reserved[0], yp = var.reserved[1], * xl = var.xres, yl = var.yres */static void set_win_position(char *id, u32 xp, u32 yp, u32 xl, u32 yl)     //設置指定的窗口的位置{	int i = 0;		DBGENTER;	if (is_win(id, VID0))  {		i = 0;	/*printk("\n==============================>");printk("==============================>");printk("==============================>");	printk("Video Window 0 X Pixel Offset =%d\n", xp);	printk("Video Window 0 Y Pixel Offset =%d\n", yp);	printk("Video Window 0 X length =%d\n", xl);	printk("Video Window 0 Y length =%d\n", yl);	printk("VID0 XRES = =%d\n", VID0_XRES);	*/}	else if (is_win(id, VID1)) {		i = 1;/*printk("\n==============================>");printk("==============================>");printk("==============================>");	printk("Video Window 1 X Pixel Offset =%d\n", xp);	printk("Video Window 1 Y Pixel Offset =%d\n", yp);	printk("Video Window 1 X length =%d\n", xl);	printk("Video Window 1 Y length =%d\n", yl);		dispc_reg_out(OSD_WINXP(i), OSD0_XRES+16);	dispc_reg_out(OSD_WINYP(i), OSD0_YRES+16);	dispc_reg_out(OSD_WINXL(i), 712);	dispc_reg_out(OSD_WINYL(i), 480);*/}	else if (is_win(id, OSD0))  {		i = 2;/*	printk("OSD Window 0 X Pixel Offset =%d\n", xp);	printk("OSD Window 0 Y Pixel Offset =%d\n", yp);	printk("OSD Window 0 X length =%d\n", xl);	printk("OSD Window 0 Y length =%d\n", yl);*/	}	else if (is_win(id, OSD1))  {		i = 3;//	printk("OSD Window 1 X Pixel Offset =%d\n", xp);//	printk("OSD Window 1 Y Pixel Offset =%d\n", yp);//	printk("OSD Window 1 X length =%d\n", xl);//	printk("OSD Window 1 Y length =%d\n", yl);	}		dispc_reg_out(OSD_WINXP(i), xp);	dispc_reg_out(OSD_WINYP(i), yp);	dispc_reg_out(OSD_WINXL(i), xl);	dispc_reg_out(OSD_WINYL(i), yl);	DBGEXIT;}static inline void get_win_position(struct dm_win_info *w,   //獲取指定的窗口w的位置
				u32 *xp, u32 *yp, u32 *xl, u32 *yl){	struct fb_var_screeninfo *v = &w->info.var;	*xp = x_pos(w);	*yp = y_pos(w);	*xl = v->xres;	*yl = v->yres;}/* Returns 1 if the windows overlap, 0 otherwise */    //窗口w與指定的坐標之間有重疊返回1，否則0static int window_overlap(struct dm_win_info *w, 			  u32 xp, u32 yp, u32 xl, u32 yl){	u32 _xp = 0, _yp = 0, _xl = 0, _yl = 0;#define OVERLAP(x1, y1, x2, y2, x3, y3, x4, y4)		\(!(	((x1)<(x3) && (x2)<(x3)) || ((x1)>(x4) && (x2)>(x4)) ||	\	((y1)<(y3) && (y2)<(y3)) || ((y1)>(y4) && (y2)>(y4)) )	\)	DBGENTER; //進入調試	if (!w)		RETURN(0);	get_win_position(w, &_xp, &_yp, &_xl, &_yl);		RETURN(OVERLAP(xp, yp, xp + xl, yp + yl,			_xp, _yp, _xp + _xl, _yp + _yl));#undef OVERLAP			}/* Returns 1 if the window parameters are within VID0, 0 otherwise */ //指定坐標的窗口是否在VID0中static int within_vid0_limits(u32 xp, u32 yp, u32 xl, u32 yl){	u32 vid0_xp = 0, vid0_yp = 0, vid0_xl = 0, vid0_yl = 0;		DBGENTER;	if (!dm.vid0)		RETURN(1);	get_win_position(dm.vid0, &vid0_xp, &vid0_yp, &vid0_xl, &vid0_yl);	if ((xp >= vid0_xp) && (yp >= vid0_yp) &&	    (xp + xl <= vid0_xp + vid0_xl) && (yp + yl <= vid0_yp + vid0_yl))		RETURN(1);	RETURN(0);}/* VID0 must be large enough to hold all other windows */static int check_new_vid0_size(u32 xp0, u32 yp0, u32 xl0, u32 yl0)  /*vid0必須足夠大，讓所有的其它窗口包含在VID0中*/{	u32 _xp = 0, _yp = 0, _xl = 0, _yl = 0;#define WITHIN_LIMITS 				\	((_xp >= xp0) && (_yp >= yp0) &&	\	(_xp + _xl <= xp0 + xl0) && (_yp + _yl <= yp0 + yl0))	if (dm.osd0) {		get_win_position(dm.osd0, &_xp, &_yp, &_xl, &_yl);		if (!WITHIN_LIMITS)			RETURN(-EINVAL);	}	if (dm.osd1) {		get_win_position(dm.osd1, &_xp, &_yp, &_xl, &_yl);		if (!WITHIN_LIMITS)			RETURN(-EINVAL);	}			if (dm.vid1) {		get_win_position(dm.vid1, &_xp, &_yp, &_xl, &_yl);		if (!WITHIN_LIMITS)			RETURN(-EINVAL);	}			RETURN(0);		#undef WITHIN_LIMITS	}/*---------------------------------------------------------------------------*//** *      dm64xxfb_check_var - Validates a var passed in.  *      @var: frame buffer variable screen structure *      @info: frame buffer structure that represents a single frame buffer  * *	Checks to see if the hardware supports the state requested by *	var passed in. This function does not alter the hardware state!!!  *	This means the data stored in struct fb_info and struct xxx_par do  *      not change. This includes the var inside of struct fb_info.  *	Do NOT change these. This function can be called on its own if we *	intent to only test a mode and not actually set it. *	If the var passed in is slightly off by what the hardware can support  *	then we alter the var PASSED in to what we can do. * *	Returns negative errno on error, or zero on success. */static int dm64xxfb_check_var(struct fb_var_screeninfo *var,	//檢查var中的設置是否滿足硬件的支持要求，可能會跟據需要改變var的設置			      struct fb_info *info){	const struct dm_win_info *w = (const struct dm_win_info *) info->par;
	struct fb_var_screeninfo v;	/* Rules: * 1) Vid1, OSD0, OSD1 and Cursor must be fully contained inside of Vid0. * 2) Vid0 and Vid1 are both set to accept YUV 4:2:2 (for now). * 3) OSD window data is always packed into 32-bit words and left justified. * 4) Each horizontal line of window data must be a multiple of 32 bytes. *    32 bytes = 32 bytes / 2 bytes per pixel = 16 pixels. *    This implies that 'xres' must be a multiple of 32 bytes. * 5) The offset registers hold the distance between the start of one line and  *    the start of the next. This offset value must be a multiple of 32 bytes. *    This implies that 'xres_virtual' is also a multiple of 32 bytes. Note  *    that 'xoffset' needn't be a multiple of 32 bytes. * 6) OSD0 is set to accept RGB565. * 	dispc_reg_merge(OSD_OSDWIN0ND, OSD_OSDWIN0ND_RGB0E, OSD_OSDWIN0ND_RGB0E) * 7) OSD1 is set to be the attribute window. * 8) Vid1 startX = Vid0 startX + N * 16 pixels (32 bytes) * 9) Vid1 width = (16*N - 8) pixels * 10) When one of the OSD windows is in RGB565, it cannot overlap with Vid1. * 11) Vid1 start X position must be offset a multiple of 16 pixels from the  * left edge of Vid0. */ 	DBGENTER;	memcpy(&v, var, sizeof(v));        RETURN(0);	/* do board-specific checks on the var */	if (dm64xx_venc_check_mode(w, &v))		RETURN(-EINVAL); 	if (v.xres_virtual < v.xres || v.yres_virtual < v.yres)		RETURN(-EINVAL);	if (v.xoffset > v.xres_virtual - v.xres)		RETURN(-EINVAL);	if (v.yoffset > v.yres_virtual - v.yres)		RETURN(-EINVAL);	if (    //(v.xres * v.bits_per_pixel/8) % 32 || 	    (v.xres_virtual * v.bits_per_pixel/8) % 32)	/* Rules 4, 5 */			RETURN(-EINVAL);	if (v.xres_virtual * v.yres_virtual * v.bits_per_pixel/8  > w->fb_size) //總的像素數大于FB緩沖區		RETURN(-EINVAL);			if (!is_win(info->fix.id, VID0)) {		/* Rule 1 */ /*When one of the OSD windows is in RGB565, it cannot overlap with Vid1. *///                printk("****Going into vid0_limits*****\n");//                printk("X Position: %d, Y Position: %d, X Length: %d, Y Length: %d\n",x_pos(w), y_pos(w), v.xres, v.yres);		if (!within_vid0_limits(x_pos(w), y_pos(w), 					v.xres, v.yres))			RETURN(-EINVAL);	    	}	if (is_win(info->fix.id, OSD0)) {		/* Rule 10 */		if (window_overlap(w->dm->vid1,				   x_pos(w), y_pos(w),				   v.xres, v.yres))			RETURN(-EINVAL);		/* Rule 5 */					v.bits_per_pixel = 16;		v.red.offset = 11;		v.green.offset = 5;		v.blue.offset = 0;		v.red.length = 5;		v.green.length = 6;		v.blue.length = 5;		v.transp.offset = v.transp.length = 0;		v.red.msb_right = v.green.msb_right = v.blue.msb_right 				= v.transp.msb_right = 0;		v.nonstd = 0;		v.accel_flags = 0;	}	else if (is_win(info->fix.id, OSD1)) {		v.bits_per_pixel = 4;	}	else if (is_win(info->fix.id, VID0)) {		if (check_new_vid0_size(x_pos(w), y_pos(w),					v.xres, v.yres))			RETURN(-EINVAL);		    		v.bits_per_pixel = 16;	}	else if (is_win(info->fix.id, VID1)) {		/* Rule 10 */                /* REVISIT: Confirm that overlapping VID1, OSD0 is ok */ //		if (window_overlap(w->dm->osd0,//			 	   x_pos(w), y_pos(w),//			  	   v.xres, v.yres))//			RETURN(-EINVAL);		/* Rule 11 */		if ((x_pos(w->dm->vid0) - x_pos(w)) % 16)			RETURN(-EINVAL);		/* Video1 may be in YUV or RGB888 format */			if ((v.bits_per_pixel != 16) && (v.bits_per_pixel != 32))			RETURN(-EINVAL);		v.bits_per_pixel = 32;		v.red.offset = 16;		v.green.offset = 8;		v.blue.offset = 0;		v.red.length = 8;		v.green.length = 8;		v.blue.length = 8;		v.transp.offset = v.transp.length = 0;		v.red.msb_right = v.green.msb_right = v.blue.msb_right 				= v.transp.msb_right = 0;	}	else 		RETURN(-EINVAL);			memcpy(var, &v, sizeof(v));	RETURN(0);}/* Interlaced = Frame mode, Non-interlaced = Field mode */static void set_interlaced(char *id, unsigned int on)			//把顯示顯示設為幀模式{	on = (on == 0) ? 0 : ~0;		DBGENTER;	if (is_win(id, VID0))		dispc_reg_merge(OSD_VIDWINMD, on, OSD_VIDWINMD_VFF0); 	else if (is_win(id, VID1)) 		dispc_reg_merge(OSD_VIDWINMD, on, OSD_VIDWINMD_VFF1); 	else if (is_win(id, OSD0))		dispc_reg_merge(OSD_OSDWIN0MD, on, OSD_OSDWIN0MD_OFF0); 	else if (is_win(id, OSD1)) 		dispc_reg_merge(OSD_OSDWIN1MD, on, OSD_OSDWIN1MD_OFF1); 	DBGEXIT;}/* For zooming, we just have to set the start of framebuffer, the zoom factors  * and the display size. The hardware will then read only  * (display size / zoom factor) area of the framebuffer and  zoom and  * display it. In the following function, we assume that the start of  * framebuffer and the display size parameters are set already. */static void set_zoom(int WinID, int h_factor, int v_factor) //設置放大的因數{	DBGENTER;	switch(WinID){	case 0: //VID0		dispc_reg_merge(OSD_VIDWINMD, 				h_factor << OSD_VIDWINMD_VHZ0_SHIFT,				OSD_VIDWINMD_VHZ0);		dispc_reg_merge(OSD_VIDWINMD, 				v_factor << OSD_VIDWINMD_VVZ0_SHIFT,				OSD_VIDWINMD_VVZ0);		break;	case 1: //VID1		dispc_reg_merge(OSD_VIDWINMD, 				h_factor << OSD_VIDWINMD_VHZ1_SHIFT,				OSD_VIDWINMD_VHZ1);		dispc_reg_merge(OSD_VIDWINMD, 				v_factor << OSD_VIDWINMD_VVZ1_SHIFT,				OSD_VIDWINMD_VVZ1);		break;	case 2://OSD0
		dispc_reg_merge(OSD_OSDWIN0MD, 
				h_factor << OSD_OSDWIN0MD_OHZ0_SHIFT,
				OSD_OSDWIN0MD_OHZ0);
		dispc_reg_merge(OSD_OSDWIN0MD, 
				v_factor << OSD_OSDWIN0MD_OVZ0_SHIFT,
				OSD_OSDWIN0MD_OVZ0);
		break;
	case 3:
		dispc_reg_merge(OSD_OSDWIN1MD, 
				h_factor << OSD_OSDWIN1MD_OHZ1_SHIFT,
				OSD_OSDWIN1MD_OHZ1);
		dispc_reg_merge(OSD_OSDWIN1MD, 
				v_factor << OSD_OSDWIN1MD_OVZ1_SHIFT,
				OSD_OSDWIN1MD_OVZ1);
		break;
	}
	DBGEXIT;
}/* Chooses the ROM CLUT for now. Can be extended later. */static void set_bg_color(u8 clut, u8 color_offset)    //設置背景顏色{	clut = 0;	/* 0 = ROM, 1 = RAM */

	DBGENTER;
	dispc_reg_merge(OSD_MODE, OSD_MODE_BCLUT & clut, OSD_MODE_BCLUT);
	dispc_reg_merge(OSD_MODE, color_offset << OSD_MODE_CABG_SHIFT, 
			OSD_MODE_CABG);
	DBGEXIT;}static void set_sdram_params(char *id, u32 addr, u32 line_length) //設置指定窗口的ram的地址{	DBGENTER;	/* The parameters to be written to the registers should be in 	 * multiple of 32 bytes	 */ 		addr = addr ;  /* div by 32 */	line_length = line_length /32 ;