使用结构体 file_operations封装驱动设备的操作

 1 /*
 2 2018-10-18
 3 功能: 第一个驱动程序;
 4 */
 5 
 6 #include <linux/module.h>
 7 #include <linux/kernel.h>
 8 #include <linux/fs.h>
 9 #include <linux/init.h>
10 #include <linux/delay.h>
11 #include <asm/uaccess.h>
12 #include <asm/irq.h>
13 #include <asm/io.h>
14 #include <asm/arch/regs-gpio.h>
15 #include <asm/hardware.h>
16 
17 static int first_drv_open(struct inode * inode, struct file *file)
18 {
19     printk("first_drv_open\n");
20 }
21 
22 static ssize_t first_drv_write(struct file *file, const char __usr *buf, size_t count, loff_t * ppos)
23 {
24     printk("first_drv_write\n");
25 }
26 
27 static struct file_operations first_drv_fops =
28 {
29     .owner = THIS_MODULE,
30     .open  = first_drv_open,
31     .write = first_drv_write
32 };
33 
34 int major;
35 static int first_drv_init(void)
36 {
37     major = register_chrdev(0, "first_drv", &first_drv_fops);
38     firstdrv_class = class_create(THIS_MODULE, "firstdrv");
39     first_class_dev = class_device_create(firstdrv_class, NULL, MKDEV(major, 0), NULL, "xyz");
40     gpfcon = (volatile unsigned long *)ioremap(0x56000050, 16);
41     gpfdat = gpfcon + 1;
42     return 0;
43 }
44 
45 static void first_drv_exit(void)
46 {
47     unregister_chrdev(major, "first_drv");
48     class_device_unregister(firstdrv_class_dev);
49     class_destroy(firstdrv_class);
50 }
51 
52 module_init(first_drv_init);
53 module_exit(first_drv_exit);
54 MODULE_LICENSE("GPL");

 1 #ifndef _LCD_H
 2 #define _LCD_H
 3 
 4 
 5 enum {
 6     NORMAL = 0,
 7     INVERT = 1,
 8 };
 9 
10 /* NORMAL : 正常极性
11  * INVERT : 反转极性
12  */
13 typedef struct pins_polarity {
14     int de;    /* normal: 高电平时可以传输数据 */
15     int pwren; /* normal: 高电平有效 */
16     int vclk;  /* normal: 在下降沿获取数据 */
17     int rgb;   /* normal: 高电平表示1 */
18     int hsync; /* normal: 高脉冲 */
19     int vsync; /* normal: 高脉冲 */
20 }pins_polarity, *p_pins_polarity;
21 
22 typedef struct time_sequence {
23     /* 垂直方向 */
24     int tvp; /* vysnc脉冲宽度 */
25     int tvb; /* 上边黑框, Vertical Back porch */
26     int tvf; /* 下边黑框, Vertical Front porch */
27 
28     /* 水平方向 */
29     int thp; /* hsync脉冲宽度 */
30     int thb; /* 左边黑框, Horizontal Back porch */
31     int thf; /* 右边黑框, Horizontal Front porch */
32 
33     int vclk;
34 }time_sequence, *p_time_sequence;
35 
36 
37 typedef struct lcd_params {
38     char *name;
39     
40     /* 引脚极性 */
41     pins_polarity pins_pol;
42     
43     /* 时序 */
44     time_sequence time_seq;
45     
46     /* 分辨率, bpp */
47     int xres;
48     int yres;
49     int bpp;
50     
51     /* framebuffer的地址 */
52     unsigned int fb_base;
53 }lcd_params, *p_lcd_params;
54 
55 void get_lcd_params(unsigned int *fb_base, int *xres, int *yres, int *bpp);
56 
57 #endif /* _LCD_H */

#include "lcd.h"

#define LCD_FB_BASE 0x33c00000

lcd_params lcd_4_3_params = {
    .name = "lcd_4.3",
    .pins_pol = {
        .de    = NORMAL,    /* normal: 高电平时可以传输数据 */
        .pwren = NORMAL,    /* normal: 高电平有效 */
        .vclk  = NORMAL,    /* normal: 在下降沿获取数据 */
        .rgb   = NORMAL,    /* normal: 高电平表示1 */
        .hsync = INVERT,    /* normal: 高脉冲 */
        .vsync = INVERT,     /* normal: 高脉冲 */
    },
    .time_seq = {
        /* 垂直方向 */
        .tvp=    10, /* vysnc脉冲宽度 */
        .tvb=    2,  /* 上边黑框, Vertical Back porch */
        .tvf=    2,  /* 下边黑框, Vertical Front porch */

        /* 水平方向 */
        .thp=    41, /* hsync脉冲宽度 */
        .thb=    2,  /* 左边黑框, Horizontal Back porch */
        .thf=    2,  /* 右边黑框, Horizontal Front porch */

        .vclk=    9,  /* MHz */
    },
    .xres = 480,
    .yres = 272,
    .bpp  = 32,  /* 16, no 24bpp */
    .fb_base = LCD_FB_BASE,
};


void lcd_4_3_add(void)
{
    register_lcd(&lcd_4_3_params);
}