Linux-2.6.39在Tiny6410上的移植 - 外设驱动移植

Linux内核版本号：linux 2.6.39

交叉编译工具：arm-linux-gcc 4.5.1

Linux内核下载：www.kernel.org

开发板：友善之臂Tiny6410

LCD：友善之臂S70

一、移植LED驱动

打开arch/arm/mach-s3c64xx/mach-mini6410.c添加下列代码：

 1 static struct gpio_led tiny6410_gpio_led[] = {
 2     [0] = {
 3         .name = "led1",              //设备名
 4         .gpio = S3C64XX_GPK(4),      //GPK4  
 5         .active_low = 1,             //低电平点亮
 6         .default_state = LEDS_GPIO_DEFSTATE_ON,        //系统启动后默认为打开
 7     },
 8     [1] = {
 9         .name = "led2",
10         .gpio = S3C64XX_GPK(5),
11         .active_low = 1,
12         .default_state = LEDS_GPIO_DEFSTATE_OFF,       //系统启动后默认关闭
13     },
14     [2] = {
15         .name = "led3",
16         .gpio = S3C64XX_GPK(6),
17         .active_low = 1,
18         .default_state = LEDS_GPIO_DEFSTATE_ON,
19     },
20     [3] = {
21         .name = "led4",
22         .gpio = S3C64XX_GPK(7),
23         .active_low = 1,
24         .default_state = LEDS_GPIO_DEFSTATE_OFF,
25     },
26 };
27 
28 static struct gpio_led_platform_data tiny6410_leds_data = {
29     .num_leds = ARRAY_SIZE(tiny6410_gpio_led),
30     .leds = &tiny6410_gpio_led,
31 };
32 
33 static struct platform_device tiny6410_device_leds = {
34     .name = "leds-gpio",
35     .id = -1,
36     .dev = {
37         .platform_data = &tiny6410_leds_data,
38     },
39 };

在mini6410_devices中添加tiny6410_device_leds，系统启动时将自动注册LED平台设备：

1 static struct platform_device *mini6410_devices[] __initdata = {
2     ...
3     &tiny6410_device_leds,
4 };

执行make menuconfig修改内核配置，添加对LED设备的支持：

Device Drivers --->

│ │ [*] LED Support --->

│ │ [*] LED Class Support
│ │ *** LED drivers ***
│ │ <*> LED Support for GPIO connected LEDs
│ │ [*] Platform device bindings for GPIO LEDs

编译并烧写内核，启动开发板可以看到第一、第三个LED被点亮。

编写应用程序控制LED：

系统LED设备名为每个LED设备创建了一个节点文件夹，位于/sys/devices/platform/leds-gpio/leds/目录下，对设备文件夹里面的brightness 文件写0或写非0即可对LED进行操作。

 1 #include <stdio.h>
 2 #include <sys/stat.h>
 3 #include <sys/types.h>
 4 #include <fcntl.h>
 5 #include <stdlib.h>
 6 #include <string.h>
 7 
 8 
 9 int main(int argc,char** argv)
10 {
11     int fd = 0;
12     char path[64] = "/sys/devices/platform/leds-gpio/leds/";
13     
14     if(argc != 3)
15     {
16         printf("format error!\n");
17         return -1;
18     }
19     
20     strcat(path,argv[1]);
21     strcat(path,"/brightness");
22     
23     printf("%s\n",path);
24     fd = open(path,O_RDWR);
25     if(fd == -1)
26     {
27         printf("open file failure!\n");
28         return -1;
29     }
30     if(atoi(argv[2]))
31         write(fd,"1",1);
32     else
33         write(fd,"0",1);
34     
35     close(fd);
36     return 0;
37 }

二、按键驱动移植

在arch/arm/mach-s3c64xx/mach-mini6410.c添加下列代码：

 1 static struct gpio_keys_button tiny6410_gpio_keys[] = {
 2     [0] = {
 3         .code            = KEY_F1,        //键值
 4         .type            = EV_KEY,        //按键输入类型
 5         .gpio            = S3C64XX_GPN(0),
 6         .active_low        = 1,           //低电平表示按下
 7         .wakeup            = 0,
 8         .debounce_interval    = 5, /* ms */    //延时消抖
 9         .desc            = "Button 1",
10     },
11     [1] = {
12         .code            = KEY_F2,
13         .type            = EV_KEY,
14         .gpio            = S3C64XX_GPN(1),
15         .active_low        = 1,
16         .wakeup            = 0,
17         .debounce_interval    = 5, /* ms */
18         .desc            = "Button 2",
19     },
20     [2] = {
21         .code            = KEY_F3,
22         .type            = EV_KEY,
23         .gpio            = S3C64XX_GPN(2),
24         .active_low        = 1,
25         .wakeup            = 0,
26         .debounce_interval    = 5, /* ms */
27         .desc            = "Button 3",
28     },
29     [3] = {
30         .code            = KEY_F4,
31         .type            = EV_KEY,
32         .gpio            = S3C64XX_GPN(3),
33         .active_low        = 1,
34         .wakeup            = 0,
35         .debounce_interval    = 5, /* ms */
36         .desc            = "Button 4",
37     },
38     
39 };
40 
41 static struct gpio_keys_platform_data tiny6410_key_data = {
42     .buttons = &tiny6410_gpio_keys,
43     .nbuttons = ARRAY_SIZE(tiny6410_gpio_keys),
44 };
45 
46 static struct platform_device tiny6410_device_keys = {
47     .name = "gpio-keys",
48     .id = -1,
49     .dev = {
50         .platform_data = &tiny6410_key_data,
51     },
52 };

在mini6410_devices中添加tiny6410_device_keys:

1 static struct platform_device *mini6410_devices[] __initdata = {
2     ....
3     &tiny6410_device_leds,
4     &tiny6410_device_keys,
5 };

执行make menuconfig修改内核配置，添加对LED设备的支持：

Device Drivers --->

│ │ Input device support --->

│ │ [*] Keyboards --->
│ │ <*> GPIO Buttons
同时在Input device support里面添加event interface的支持，在/dev/下面就能生成一个event设备文件：

Device Drivers --->

│ │ Input device support --->

│ │ <*> Event interface

编译并烧写内核，启动开发板可以在/dev/目录下生成了event0设备文件，对按键驱动进行简单的测试：

执行hexdump /dev/event0

每次按下按键可以看到如下所示按键信息，表明按键是工作正常的。

1 /dev # hexdump event0
2 0000000 034d 0000 0e3b 000c 0001 003b 0001 0000
3 0000010 034d 0000 0e4c 000c 0000 0000 0000 0000
4 0000020 034d 0000 cd5f 000e 0001 003b 0000 0000
5 0000030 034d 0000 cd6b 000e 0000 0000 0000 0000

编写应用程序测试按键驱动：

按键驱动为输入子系统，应用程序中需要对event进行循环检测看系统有没有上报输入事件，按键的输入事件类型为EV_KEY，键值分别问KEY_F1、KEY_F2、KEY_F3、KEY_F4，数值为1表示按键按下为0表示按键释放。

 1 #include <stdio.h>
 2 #include <sys/stat.h>
 3 #include <sys/types.h>
 4 #include <fcntl.h>
 5 #include <stdlib.h>
 6 #include <linux/input.h>
 7 
 8 int main(void)
 9 {
10     int fd = 0;
11     struct input_event event_key;
12     int count = 0;
13     
14     fd = open("/dev/event0",O_RDONLY);
15     if(fd == -1)
16     {
17         printf("open file failed\n");
18         return -1;
19     }
20     
21     while(1)
22     {
23         count = read(fd,&event_key,sizeof(struct input_event));
24         if(count < 0)
25         {
26             printf("read failed\n");
27             break;
28         }
29         if(event_key.type == EV_KEY)
30         {
31             switch(event_key.code)
32             {
33                 case KEY_F1:
34                 {
35                     if(event_key.value == 1)
36                         printf("key1 pressed\n");
37                     else if(event_key.value == 0)
38                         printf("key1 released\n");
39                 }
40                 break;
41                 case KEY_F2:
42                 {
43                     if(event_key.value == 1)
44                         printf("key2 pressed\n");
45                     else if(event_key.value == 0)
46                         printf("key2 released\n");
47                 }
48                 break;
49                 case KEY_F3:
50                 {
51                     if(event_key.value == 1)
52                         printf("key3 pressed\n");
53                     else if(event_key.value == 0)
54                         printf("key3 released\n");
55                 }
56                 break;
57                 case KEY_F4:
58                 {
59                     if(event_key.value == 1)
60                         printf("key4 pressed\n");
61                     else if(event_key.value == 0)
62                         printf("key4 released\n");
63                 }
64                 break;
65             }
66         }
67         
68     }
69     
70     close(fd);
71     return 0;
72 }

三、LCD显示屏移植

在arch/arm/mach-s3c64xx/mach-mini6410.c修改显示代码：

 1 static struct s3c_fb_pd_win mini6410_fb_win[] = {
 2     {
 3         .win_mode    = {    /* 7.0" 800x480 */
 4             .left_margin    = 0x2c,//26,    
 5             .right_margin    = 0xd2,//210,   
 6             .upper_margin    = 0x15,//13,     
 7             .lower_margin    = 0x16,//22,    
 8             .hsync_len    = 0x02,//20,
 9             .vsync_len    = 0x02,//10,
10             .xres        = 800,
11             .yres        = 480,
12         },
13         .max_bpp    = 32,
14         .default_bpp    = 16,
15     }, 
16 };

参数的值根据LCD显示屏规格书确定，具体参数解释及计算见博客http://blog.csdn.net/longxiaowu/article/details/24319933

执行make menuconfig修改内核配置，添加对LCD设备的支持：

Device Drivers --->

│ │ Input device support --->

│ │ Graphics support --->

│ │ <*> Support for frame buffer devices --->

│ │ <*> Samsung S3C framebuffer support

│ │ [*] Bootup logo ---> //开机显示小企鹅

│ │ --- Bootup logo │ │
│ │ [ ] Standard black and white Linux logo
│ │ [ ] Standard 16-color Linux logo
│ │ [*] Standard 224-color Linux logo

编译烧写内核并开机，屏幕上并没有看到小企鹅。加载Tiny6410一线触摸设备驱动之后小企鹅出来了，应该是Tiny6410 S70屏幕的背光是在一线触摸中进行打开的，由于一线触摸的协议并不开源所以没有进行深究。

四、触摸屏校验程序tslib移植

见博客：http://www.cnblogs.com/ape-ming/p/5134542.html

posted on 2016-02-24 11:44 青春没有尾巴阅读(905) 评论(0) 编辑收藏举报