嵌入式Linux之我行——S3C2440上LCD驱动(FrameBuffer)实例开发解说

structfb_info{
intnode;
intflags;
structfb_var_screeninfo var;
structfb_fix_screeninfo fix;
structfb_monspecs monspecs;
structwork_structqueue;
structfb_pixmap pixmap;
structfb_pixmap sprite;
structfb_cmap cmap;
structfb_videomode*mode;

#ifdefCONFIG_FB_BACKLIGHT
structbacklight_device*bl_dev;
structmutex bl_curve_mutex;
u8 bl_curve[FB_BACKLIGHT_LEVELS];
#endif
#ifdefCONFIG_FB_DEFERRED_IO
structdelayed_work deferred_work;
structfb_deferred_io*fbdefio;
#endif

structfb_ops*fbops;
structdevice*device;
structdevice*dev;
intclass_flag;
#ifdefCONFIG_FB_TILEBLITTING
structfb_tile_ops*tileops;
#endif
char__iomem*screen_base;
unsignedlongscreen_size;
void*pseudo_palette;
#defineFBINFO_STATE_RUNNING0
#defineFBINFO_STATE_SUSPENDED1
u32 state;
void*fbcon_par;
void*par;
};

structfb_var_screeninfo{
__u32 xres;
__u32 yres;
__u32 xres_virtual;
__u32 yres_virtual;
__u32 xoffset;
__u32 yoffset;
__u32 bits_per_pixel;
__u32 grayscale;

structfb_bitfield red;
structfb_bitfield green;
structfb_bitfield blue;
structfb_bitfield transp;

__u32 nonstd;
__u32 activate;
__u32 height;
__u32 width;
__u32 accel_flags;

__u32 pixclock;
__u32 left_margin;
__u32 right_margin;
__u32 upper_margin;
__u32 lower_margin;
__u32 hsync_len;
__u32 vsync_len;
__u32 sync;
__u32 vmode;
__u32rotate;
__u32 reserved[5];
};

structfb_fix_screeninfo{
charid[16];
unsignedlongsmem_start;
__u32 smem_len;
__u32 type;
__u32 type_aux;
__u32 visual;
__u16 xpanstep;
__u16 ypanstep;
__u16 ywrapstep;
__u32 line_length;
unsignedlongmmio_start;
__u32 mmio_len;
__u32 accel;
__u16 reserved[3];
};

structfb_ops{

structmodule*owner;

//查看可变参数并进行设置
int(*fb_check_var)(structfb_var_screeninfo*var,structfb_info*info);

//依据设置的值进行更新，使之有用
int(*fb_set_par)(structfb_info*info);

//设置色彩寄存器
int(*fb_setcolreg)(unsignedregno,unsignedred,unsignedgreen,
unsignedblue,unsignedtransp,structfb_info*info);

//显现空白
int(*fb_blank)(intblank,structfb_info*info);

//矩形填充
void(*fb_fillrect)(structfb_info*info,conststructfb_fillrect*rect);

//仿制数据
void(*fb_copyarea)(structfb_info*info,conststructfb_copyarea*region);

//图形填充
void(*fb_imageblit)(structfb_info*info,conststructfb_image*image);
};

//LCD操控器的资源信息
staticstructresource s3c_lcd_resource[]={
[0]={
.start=S3C24XX_PA_LCD,//操控器IO端口开端地址
.end=S3C24XX_PA_LCD+S3C24XX_SZ_LCD–1,//操控器IO端口完毕地址
.flags=IORESOURCE_MEM,//标识为LCD操控器IO端口，在驱动中引证这个就一共引证IO端口
},
[1]={
.start=IRQ_LCD,//LCD中止
.end=IRQ_LCD,
.flags=IORESOURCE_IRQ,//标识为LCD中止
}
};

staticu64 s3c_device_lcd_dmamask=0xffffffffUL;

structplatform_device s3c_device_lcd={
.name=“s3c2410-lcd”,//作为渠道设备的LCD设备名
.id=-1,
.num_resources=ARRAY_SIZE(s3c_lcd_resource),//资源数量
.resource=s3c_lcd_resource,//引证上面界说的资源
.dev={
.dma_mask=&s3c_device_lcd_dmamask,
.coherent_dma_mask=0xffffffffUL
}
};

EXPORT_SYMBOL(s3c_device_lcd);//导出界说的LCD渠道设备，好在mach-smdk2440.c的smdk2440_devices[]中添加到渠道设备列表中

//LCD硬件的装备信息，留心这儿我运用的LCD是NEC 3.5寸TFT屏，这些参数要依据详细的LCD屏进行设置
staticstructs3c2410fb_display smdk2440_lcd_cfg __initdata={

//这个当地的设置是装备LCD寄存器5，这些宏界说在regs-lcd.h中，核算后二进制为：111111111111，然后对照数据手册上LCDCON5的各位来看，留心是从右边开端
.lcdcon5=S3C2410_LCDCON5_FRM565|
S3C2410_LCDCON5_INVVLINE|
S3C2410_LCDCON5_INVVFRAME|
S3C2410_LCDCON5_PWREN|
S3C2410_LCDCON5_HWSWP,

.type=S3C2410_LCDCON1_TFT,//TFT类型

.width=240,//屏幕宽度
.height=320,//屏幕高度

//以下一些参数在上面的时序图剖析中讲到过,各参数的值请跟据详细的LCD屏数据手册结合上面时序剖析来设定
.pixclock=100000,//像素时钟
.xres=240,//水平可见的有用像素
.yres=320,//笔直可见的有用像素
.bpp=16,//色位形式
.left_margin=19,//行切换，从同步到绘图之间的推迟
.right_margin=36,//行切换，从绘图到同步之间的推迟
.hsync_len=5,//水平同步的长度
.upper_margin=1,//帧切换，从同步到绘图之间的推迟
.lower_margin=5,//帧切换，从绘图到同步之间的推迟
.vsync_len=1,//笔直同步的长度
};

staticstructs3c2410fb_mach_info smdk2440_fb_info __initdata={
.displays=&smdk2440_lcd_cfg,//运用上面界说的装备信息
.num_displays=1,
.default_display=0,

.gpccon=0xaaaa555a,//将GPC0、GPC1装备成LEND和VCLK，将GPC8-15装备成VD0-7,其他装备成一般输出IO口
.gpccon_mask=0xffffffff,
.gpcup=0x0000ffff,//制止GPIOC的上拉功用
.gpcup_mask=0xffffffff,
.gpdcon=0xaaaaaaaa,//将GPD0-15装备成VD8-23
.gpdcon_mask=0xffffffff,
.gpdup=0x0000ffff,//制止GPIOD的上拉功用
.gpdup_mask=0xffffffff,

.lpcsel=0x0,//这个是三星TFT屏的参数，这儿不必
};

//S3C2440初始化函数
staticvoid__init smdk2440_machine_init(void)
{

//调用该函数将上面界说的LCD硬件信息保存到渠道数据中
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(structs3c2410fb_mach_info*pd)
{
structs3c2410fb_mach_info*npd;

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

//这儿便是将内核中界说的s3c2410fb_mach_info结构体数据保存到LCD渠道数据中，所以在写驱动的时分就能够直接在渠道数据中获取s3c2410fb_mach_info结构体的数据(即LCD各种参数信息)进行操作
s3c_device_lcd.dev.platform_data=npd;
}else{
printk(KERN_ERR“no memory for LCD platform data\n”);
}
}