struct fb_info {
    int node;
    int flags;
    struct fb_var_screeninfo var;/*LCD可變參數(shù)結(jié)構(gòu)體*/
    struct fb_fix_screeninfo fix;/*LCD固定參數(shù)結(jié)構(gòu)體*/
    struct fb_monspecs monspecs; /*LCD顯示器標(biāo)準(zhǔn)*/
    struct work_struct queue;    /*幀緩沖事件隊列*/
    struct fb_pixmap pixmap;     /*圖像硬件mapper*/
    struct fb_pixmap sprite;     /*光標(biāo)硬件mapper*/
    struct fb_cmap cmap;         /*當(dāng)前的顏色表*/
    struct fb_videomode *mode;   /*當(dāng)前的顯示模式*/

#ifdef CONFIG_FB_BACKLIGHT
    struct backlight_device *bl_dev;/*對應(yīng)的背光設(shè)備*/
    struct mutex bl_curve_mutex;
    u8 bl_curve[FB_BACKLIGHT_LEVELS];/*背光調(diào)整*/
#endif
#ifdef CONFIG_FB_DEFERRED_IO
    struct delayed_work deferred_work;
    struct fb_deferred_io *fbdefio;
#endif

    struct fb_ops *fbops; /*對底層硬件操作的函數(shù)指針*/
    struct device *device;
    struct device *dev;   /*fb設(shè)備*/
    int class_flag;    
#ifdef CONFIG_FB_TILEBLITTING
    struct fb_tile_ops *tileops; /*圖塊Blitting*/
#endif
    char __iomem *screen_base;   /*虛擬基地址*/
    unsigned long screen_size;   /*LCD IO映射的虛擬內(nèi)存大小*/
    void *pseudo_palette;        /*偽16色顏色表*/
#define FBINFO_STATE_RUNNING    0
#define FBINFO_STATE_SUSPENDED  1
    u32 state;  /*LCD的掛起或恢復(fù)狀態(tài)*/
    void *fbcon_par;
    void *par;    
};

struct fb_ops {

    struct module *owner;

    //檢查可變參數(shù)并進行設(shè)置
    int (*fb_check_var)(struct fb_var_screeninfo *var, struct fb_info *info);

    //根據(jù)設(shè)置的值進行更新，使之有效
    int (*fb_set_par)(struct fb_info *info);

    //設(shè)置顏色寄存器
    int (*fb_setcolreg)(unsigned regno, unsigned red, unsigned green,
             unsigned blue, unsigned transp, struct fb_info *info);

    //顯示空白
    int (*fb_blank)(int blank, struct fb_info *info);

    //矩形填充
    void (*fb_fillrect) (struct fb_info *info, const struct fb_fillrect *rect);

    //復(fù)制數(shù)據(jù)
    void (*fb_copyarea) (struct fb_info *info, const struct fb_copyarea *region);

    //圖形填充
    void (*fb_imageblit) (struct fb_info *info, const struct fb_image *image);
};

/* LCD Controller */

//LCD控制器的資源信息
static struct resource s3c_lcd_resource[] = {
    [0] = {
        .start = S3C24XX_PA_LCD, //控制器IO端口開始地址
        .end = S3C24XX_PA_LCD + S3C24XX_SZ_LCD - 1,//控制器IO端口結(jié)束地址
        .flags = IORESOURCE_MEM,//標(biāo)識為LCD控制器IO端口，在驅(qū)動中引用這個就表示引用IO端口
    },
    [1] = {
        .start = IRQ_LCD,//LCD中斷
        .end = IRQ_LCD,
        .flags = IORESOURCE_IRQ,//標(biāo)識為LCD中斷
    }
};

static u64 s3c_device_lcd_dmamask = 0xffffffffUL;

struct platform_device s3c_device_lcd = {
    .name         = "s3c2410-lcd",//作為平臺設(shè)備的LCD設(shè)備名
    .id         = -1,
    .num_resources = ARRAY_SIZE(s3c_lcd_resource),//資源數(shù)量
    .resource     = s3c_lcd_resource,//引用上面定義的資源
    .dev = {
        .dma_mask = &s3c_device_lcd_dmamask,
        .coherent_dma_mask = 0xffffffffUL
    }
};

EXPORT_SYMBOL(s3c_device_lcd);//導(dǎo)出定義的LCD平臺設(shè)備，好在mach-smdk2440.c的smdk2440_devices[]中添加到平臺設(shè)備列表中

/* LCD driver info */

//LCD硬件的配置信息，注意這里我使用的LCD是NEC 3.5寸TFT屏，這些參數(shù)要根據(jù)具體的LCD屏進行設(shè)置
static struct s3c2410fb_display smdk2440_lcd_cfg __initdata = {

    //這個地方的設(shè)置是配置LCD寄存器5，這些宏定義在regs-lcd.h中，計算后二進制為：111111111111，然后對照數(shù)據(jù)手冊上LCDCON5的各位來看，注意是從右邊開始
    .lcdcon5 = S3C2410_LCDCON5_FRM565 |
               S3C2410_LCDCON5_INVVLINE |
               S3C2410_LCDCON5_INVVFRAME |
               S3C2410_LCDCON5_PWREN |
               S3C2410_LCDCON5_HWSWP,

    .type    = S3C2410_LCDCON1_TFT,//TFT類型

    /* NEC 3.5'' */
    .width        = 240,//屏幕寬度
    .height       = 320,//屏幕高度

    //以下一些參數(shù)在上面的時序圖分析中講到過,各參數(shù)的值請跟據(jù)具體的LCD屏數(shù)據(jù)手冊結(jié)合上面時序分析來設(shè)定
    .pixclock     = 100000,//像素時鐘
    .xres         = 240,//水平可見的有效像素
    .yres         = 320,//垂直可見的有效像素
    .bpp          = 16,//色位模式
    .left_margin  = 19,//行切換，從同步到繪圖之間的延遲
    .right_margin = 36,//行切換，從繪圖到同步之間的延遲
    .hsync_len    = 5,//水平同步的長度
    .upper_margin = 1,//幀切換，從同步到繪圖之間的延遲
    .lower_margin = 5,//幀切換，從繪圖到同步之間的延遲
    .vsync_len    = 1,//垂直同步的長度
};

static struct s3c2410fb_mach_info smdk2440_fb_info __initdata = {
    .displays        = &smdk2440_lcd_cfg,//應(yīng)用上面定義的配置信息
    .num_displays    = 1,
    .default_display = 0,

    .gpccon          = 0xaaaa555a,//將GPC0、GPC1配置成LEND和VCLK，將GPC8-15配置成VD0-7,其他配置成普通輸出IO口
    .gpccon_mask     = 0xffffffff,
    .gpcup           = 0x0000ffff,//禁止GPIOC的上拉功能
    .gpcup_mask      = 0xffffffff,
    .gpdcon          = 0xaaaaaaaa,//將GPD0-15配置成VD8-23
    .gpdcon_mask     = 0xffffffff,
    .gpdup           = 0x0000ffff,//禁止GPIOD的上拉功能
    .gpdup_mask      = 0xffffffff,

    .lpcsel          = 0x0,//這個是三星TFT屏的參數(shù)，這里不用
};

//S3C2440初始化函數(shù)
static void __init smdk2440_machine_init(void)
{

    //調(diào)用該函數(shù)將上面定義的LCD硬件信息保存到平臺數(shù)據(jù)中
    s3c24xx_fb_set_platdata(&smdk2440_fb_info);
    
    s3c_i2c0_set_platdata(NULL);

    platform_add_devices(smdk2440_devices, ARRAY_SIZE(smdk2440_devices));
    smdk_machine_init();
}

void __init s3c24xx_fb_set_platdata(struct s3c2410fb_mach_info *pd)
{
    struct s3c2410fb_mach_info *npd;

    npd = kmalloc(sizeof(*npd), GFP_KERNEL);
    if (npd) {
        memcpy(npd, pd, sizeof(*npd));

        //這里就是將內(nèi)核中定義的s3c2410fb_mach_info結(jié)構(gòu)體數(shù)據(jù)保存到LCD平臺數(shù)據(jù)中，所以在寫驅(qū)動的時候就可以直接在平臺數(shù)據(jù)中獲取s3c2410fb_mach_info結(jié)構(gòu)體的數(shù)據(jù)(即LCD各種參數(shù)信息)進行操作
        s3c_device_lcd.dev.platform_data = npd;
    } else {
        printk(KERN_ERR "no memory for LCD platform data\n");
    }
}