struct fb_ops *fbops;帧缓冲操作函数集 struct device *device;/* This is the parent */父设备 struct device *dev;/* This is this fb device */fb设备 int class_flag; /* private sysfs flags */私有的sysfs标志 #ifdef CONFIG_FB_TILEBLITTING struct fb_tile_ops *tileops; /* Tile Blitting */图块blitting #endif char __iomem *screen_base;/* Virtual address */虚拟基地址 unsigned long screen_size;/* Amount of ioremapped VRAM or 0 */ ioremap的虚拟内存大小 void *pseudo_palette;/* Fake palette of 16 colors */ 伪16位调色板 #define FBINFO_STATE_RUNNING 0 #define FBINFO_STATE_SUSPENDED 1 u32 state; /* Hardware state i.e suspend */硬件的状态 void *fbcon_par; /* fbcon use-only private area */ /* From here on everything is device dependent */ void *par; }; （2）、/* * Frame buffer operations * * LOCKING NOTE: those functions must _ALL_ be called with the console * semaphore held, this is the only suitable locking mechanism we have * in 2.6. Some may be called at interrupt time at this point though. */ fb_ops结构体用来实现对帧缓冲设备的操作，这些函数需要驱动开发人员编写，
struct fb_ops { /* open/release and usage marking */ struct module *owner; 打开和释放 int （*fb_open）（struct fb_info *info, int user）;int （*fb_release）（struct fb_info *info, int user）;
这两个函数对于非线性布局的/常规内存映射无法工作的帧缓冲设备需要 /* For framebuffers with strange non linear layouts or that do not * work with normal memory mapped access */ ssize_t （*fb_read）（struct fb_info *info, char __user *buf, size_t count, loff_t *ppos）; ssize_t （*fb_write）（struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos）;
检测可变参数，并调整到支持的值 /* checks var and eventually tweaks it to something supported, * DO NOT MODIFY PAR */ int （*fb_check_var）（struct fb_var_screeninfo *var, struct fb_info *info）;
设置视频模式 /* set the video mode according to info->var */ int （*fb_set_par）（struct fb_info *info）;
设置color寄存器的值 /* set color register */ int （*fb_setcolreg）（unsigned regno, unsigned red, unsigned green, unsigned blue, unsigned transp, struct fb_info *info）;
批量设置color寄存器，设置颜色表 /* set color registers in batch */ int （*fb_setcmap）（struct fb_cmap *cmap, struct fb_info *info）;
pan显示 /* pan display */ int （*fb_pan_display）（struct fb_var_screeninfo *var, struct fb_info *info）;
填充矩形 /* Draws a rectangle */ void （*fb_fillrect） （struct fb_info *info, const struct fb_fillrect *rect）; 数据复制 /* Copy data from area to another */ void （*fb_copyarea） （struct fb_info *info, const struct fb_copyarea *region）; 图形填充 /* Draws a image to the display */ void （*fb_imageblit） （struct fb_info *info, const struct fb_image *image）;
绘制光标 /* Draws cursor */ int （*fb_cursor） （struct fb_info *info, struct fb_cursor *cursor）;
旋转显示 /* Rotates the display */ void （*fb_rotate）（struct fb_info *info, int angle）;
等待blit空闲 /* wait for blit idle, optional */ int （*fb_sync）（struct fb_info *info）;
fb特定的ioctl操作 /* perform fb specific ioctl （optional） */ int （*fb_ioctl）（struct fb_info *info, unsigned int cmd, unsigned long arg）;
处理32兼容的ioctl操作 /* Handle 32bit compat ioctl （optional） */ int （*fb_compat_ioctl）（struct fb_info *info, unsigned cmd, unsigned long arg）;
fb特定的mmap操作 /* perform fb specific mmap */ int （*fb_mmap）（struct fb_info *info, struct vm_area_struct *vma）;
保存目前的硬件状态 /* save current hardware state */ void （*fb_save_state）（struct fb_info *info）;
恢复被保存的硬件状态 /* restore saved state */ void （*fb_restore_state）（struct fb_info *info）;
通过fb_info获得framebuffer的能力 /* get capability given var */ void （*fb_get_caps）（struct fb_info *info, struct fb_blit_caps *caps, struct fb_var_screeninfo *var）; }; （3）、fb_fix_screeninfo结构体中，记录了用户不能修改的固定显示控制器参数。这些固定的参数如缓冲区的物理地址、缓冲区的长度等等。 struct fb_fix_screeninfo { char id[16]; /* identification string eg "TT Builtin" */ 字符串形式的标识符 unsigned long smem_start;/* Start of frame buffer mem *//* （physical address） */ fb缓存的开始位置 __u32 smem_len;/* Length of frame buffer mem */ fb缓存的长度 __u32 type; /* see FB_TYPE_* */ FB_TYPE_*类型 __u32 type_aux;/* Interleave for interleaved Planes */ 分界 __u32 visual; /* see FB_VISUAL_* */ 屏幕使用的色彩模式 __u16 xpanstep;/* zero if no hardware panning */ 如果没有硬件panning ，赋0 __u16 ypanstep;/* zero if no hardware panning */__u16 ywrapstep;/* zero if no hardware ywrap */ 1行的字节数 __u32 line_length;/* length of a line in bytes */ 内存映射I/O的开始位置 unsigned long mmio_start;/* Start of Memory Mapped I/O */ /* （physical address） */ 内存映射I/O的长度 __u32 mmio_len;/* Length of Memory Mapped I/O */ __u32 accel; /* Indicate to driver which */ /* specific chip/card we have*/ __u16 reserved[3];/* Reserved for future compatibility */ }; （4）、fb_var_screeninfo结构体中存储了用户可以修改的显示器控制参数，例如屏幕分辨率、透明度等等。
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