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通過IO端口讀取外部數(shù)據(jù)，帶中斷

作者： 時(shí)間：2016-11-20 來源：網(wǎng)絡(luò) 收藏
基于FL2440開發(fā)板，內(nèi)核版本2.6.28

主機(jī)平臺(tái)：Ubuntu 11.04 內(nèi)核版本2.6.39

本文引用地址：http://m.butianyuan.cn/article/201611/318855.htm

驅(qū)動(dòng)代碼


  1. #include
  2. #include
  3. #include
  4. #include
  5. #include
  6. #includeinterrupt.h>/*設(shè)置中斷方式*/
  7. #include
  8. #include
  10. #include
  12. #include
  13. #include
  15. //設(shè)備名
  16. #defineIO_DEVICE_NAME"my_io"
  17. //主設(shè)備號(hào)
  18. #defineIO_DEVICE_MAJOR240
  19. //次設(shè)備號(hào)
  20. #defineIO_DEVICE_SECONDARY32
  22. //返回一個(gè)數(shù)x的第y位
  23. #defineMYBIT(x,y)((x>>y)%2)
  25. #ifndef_LINUX_IRQRETURN_H
  26. #define_LINUX_IRQRETURN_H
  28. typedefintirqreturn_t;
  30. #defineIRQ_NONE(0)
  31. #defineIRQ_HANDLED(1)
  32. #defineIRQ_RETVAL(x)((x)!=0)
  33. #endif
  35. /*
  36. *S3C2410GPIOedgedetectionforIRQs:
  37. *IRQsaregeneratedonFalling-Edge,Rising-Edge,both,lowlevelorhigglevel.
  38. *Thismustbecalled*before*thecorrespondingIRQisregistered.
  39. */
  40. #defineEXT_LOWLEVEL0
  41. #defineEXT_HIGHLEVEL1
  42. #defineEXT_FALLING_EDGE2
  43. #defineEXT_RISING_EDGE4
  44. #defineEXT_BOTH_EDGES6
  47. staticintflag_0,flag_2;//中斷轉(zhuǎn)換標(biāo)志
  48. staticintcnt;
  49. intdata;
  50. DECLARE_WAIT_QUEUE_HEAD(io_wait);//聲明等待隊(duì)列
  53. voidio_con_set();
  55. staticirqreturn_tio_interrupt_0(intirq,void*dev_id,structpt_regs*regs)
  56. {
  57. if(flag_0==0)
  58. {
  59. printk("**********theinterrupt0works**********n");
  60. cnt=(cnt+1)%2;
  61. flag_0=1;
  62. if(cnt==0)
  63. {
  64. printk("INn");
  65. data=1;
  66. s3c2410_gpio_setpin(S3C2410_GPB5,0);
  67. s3c2410_gpio_setpin(S3C2410_GPB6,1);
  68. }
  69. wake_up_interruptible(&io_wait);
  70. }
  71. returnIRQ_HANDLED;
  72. }
  73. staticirqreturn_tio_interrupt_2(intirq,void*dev_id,structpt_regs*regs)
  74. {
  75. if(flag_2==0)
  76. {
  77. printk("**********theinterrupt2works**********n");
  78. cnt=(cnt+1)%2;
  79. flag_2=1;
  80. if(cnt==0)
  81. {
  82. printk("OUTn");
  83. data=0;
  84. s3c2410_gpio_setpin(S3C2410_GPB5,1);
  85. s3c2410_gpio_setpin(S3C2410_GPB6,0);
  86. }
  87. wake_up_interruptible(&io_wait);
  88. }
  89. returnIRQ_HANDLED;
  90. }
  91. staticintio_open(structinode*inode,structfile*file)//打開設(shè)備函數(shù)
  92. {
  93. intret;
  94. set_irq_type(IRQ_EINT0,EXT_FALLING_EDGE);//設(shè)置中斷0觸發(fā)方式
  95. set_irq_type(IRQ_EINT2,EXT_FALLING_EDGE);//設(shè)置中斷2觸發(fā)方式
  96. //EXT_LOWLEVEL
  97. //EXT_HIGHLEVEL
  98. //EXT_FALLING_EDGE
  99. //EXT_RISING_EDGE
  100. //EXT_BOTH_EDGES
  101. disable_irq(IRQ_EINT0);
  102. disable_irq(IRQ_EINT2);
  103. enable_irq(IRQ_EINT0);
  104. enable_irq(IRQ_EINT2);
  105. ret=request_irq(IRQ_EINT0,io_interrupt_0,IRQF_SHARED,IO_DEVICE_NAME,1);//注冊(cè)中斷0
  106. if(ret<0)
  107. {
  108. printk("IRQ%dcannotrequestn",IRQ_EINT0);
  109. returnret;
  110. }
  111. ret=request_irq(IRQ_EINT2,io_interrupt_2,IRQF_SHARED,IO_DEVICE_NAME,1);//注冊(cè)中斷2
  112. if(ret<0)
  113. {
  114. printk("IRQ%dcannotrequestn",IRQ_EINT2);
  115. returnret;
  116. }
  117. printk("thedeviceisopenedn");
  118. io_con_set();
  119. cnt=0;
  120. return0;
  121. }
  122. voidio_con_set()//IO端口控制寄存器初始化
  123. {
  124. s3c2410_gpio_cfgpin(S3C2410_GPF0,S3C2410_GPF0_EINT0);
  125. s3c2410_gpio_cfgpin(S3C2410_GPF2,S3C2410_GPF2_EINT2);
  126. s3c2410_gpio_cfgpin(S3C2410_GPB5,S3C2410_GPB5_OUTP);
  127. s3c2410_gpio_cfgpin(S3C2410_GPB6,S3C2410_GPB6_OUTP);
  128. }
  129. staticintio_close(structinode*inode,structfile*file)//設(shè)備關(guān)閉函數(shù)
  130. {
  131. free_irq(IRQ_EINT0,1);//釋放中斷
  132. free_irq(IRQ_EINT2,1);//釋放中斷
  133. printk("thedeviceisclosedn");
  134. return0;
  135. }
  136. staticssize_tio_read(structfile*filp,char*buff,size_tcount,loff_t*f_ops)//讀取IO端口
  137. {
  138. wait_event_interruptible(io_wait,flag_0&flag_2);
  139. flag_0=0;
  140. flag_2=0;
  141. copy_to_user(buff,(char*)&data,sizeof(data));
  142. }
  143. staticstructfile_operationsio_device_fops=
  144. {
  145. .owner=THIS_MODULE,
  146. .read=io_read,
  147. .open=io_open,
  148. .release=io_close,
  149. };
  151. staticint__initio_init(void)//insmod加載驅(qū)動(dòng)時(shí)執(zhí)行
  152. {
  153. intret;
  154. ret=register_chrdev(IO_DEVICE_MAJOR,IO_DEVICE_NAME,&io_device_fops);
  155. if(ret<0)
  156. {
  157. printk("Failtoregistthedevicen");
  158. returnret;
  159. }
  160. return0;
  161. }
  162. staticint__exitio_exit(void)//rmmod卸載驅(qū)動(dòng)時(shí)執(zhí)行
  163. {
  164. unregister_chrdev(IO_DEVICE_MAJOR,IO_DEVICE_NAME);
  165. printk("thedevicehasbeenunregistedn");
  166. }
  168. module_init(io_init);
  169. module_exit(io_exit);
  171. MODULE_LICENSE("GPL");

Makefile

obj-m := my_io.o

KERNELDIR ?= /arm/linux-2.6.28.7-2440

PWD := $(shell pwd)

default:

$(MAKE) -C $(KERNELDIR) M=$(PWD) modules

clean:

rm -f *.o *.ko *.order *.symvers

調(diào)用代碼：

  1. #include
  2. #include
  3. #include
  5. #defineMY_DEVICE"/dev/my_io"
  7. intmain()
  8. {
  9. intret;
  10. intdata;
  11. inti;
  12. ret=open(MY_DEVICE,0);
  13. printf("ret=%dn",ret);
  14. for(i=0;i<20;i++)
  15. {
  16. read(ret,&data,sizeof(data));
  17. printf("thedatais%dn",data);
  18. }
  19. close(ret);
  20. printf("thedeviceisclosedn");
  21. return0;
  22. }

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