实验 8-2 键盘中断驱动实验.doc

实验8-2 键盘中断驱动实验【实验目的】 掌握键盘原理。 熟悉驱动的中断机制。【实验步骤】第一步: 利用vi编辑器，编写一个Keypad.c驱动代码；1、 增加驱动所需的头文件和变量#include #include #include #include #include #include #include #include MODULE_LICENSE(GPL);#define DEVICE_NAMEemdoor_kbd#define KEYVALUE_HAVE 1#define KEYVALUE_NO 0#define KPC_DIR15#define KPC_MAT1private_data;KBD_RET kbd_ret;while(1)if(kbd-kbd_status=KEYVALUE_HAVE) kbd_ret = kbd-kbd_buff; copy_to_user(buffer, &kbd_ret, sizeof(KBD_RET); kbd-kbd_status=KEYVALUE_NO; return sizeof(KBD_RET);elseif (filp-f_flags & O_NONBLOCK) return -EAGAIN;interruptible_sleep_on(&(kbd-wq);if (signal_pending(current)return -ERESTARTSYS;return sizeof(KBD_RET);3、 实现键盘驱动中断服务例程static void Emdoor_isr_kbd(int irq, void *dev_id, struct pt_regs *reg)printk(KERN_EMERGEmdoor_isr_kbd,Interruptn);int kpc_value;KBD_DEV * kbd = (KBD_DEV *) dev_id;spin_lock_irq(&(kbd-lock);kpc_value=KPC;if(kpc_value&KPC_MAT) kbd-kbd_buff=KPAS&0xFF;if(kbd-kbd_buff!=0xFF) switch(kbd-kbd_buff)case 0x0: kbd-kbd_buff=5; break;case 0x1: kbd-kbd_buff=6; break;case 0x2: kbd-kbd_buff=7; break;case 0x5: kbd-kbd_buff=8; break;case 0x10: kbd-kbd_buff=9; break;case 0x11: kbd-kbd_buff=10; break;case 0x12: kbd-kbd_buff=11; break;case 0x15: kbd-kbd_buff=12; break;case 0x20: kbd-kbd_buff=13; break;case 0x21: kbd-kbd_buff=14; break;case 0x22: kbd-kbd_buff=15; break;case 0x25: kbd-kbd_buff=16; break;default: break;kbd-kbd_status=KEYVALUE_HAVE;else if(kpc_value&KPC_DIR)kbd-kbd_buff=KPDK&0xFF;if(kbd-kbd_buff!=0x0) switch(kbd-kbd_buff)case 0x40: kbd-kbd_buff=1; break;case 0x2: kbd-kbd_buff=2; break;case 0x4: kbd-kbd_buff=3; break;case 0x20: kbd-kbd_buff=4; break;default: break;kbd-kbd_status=KEYVALUE_HAVE;if ( fasync )kill_fasync( &(fasync), SIGIO, POLL_IN );wake_up_interruptible(&(kbd-wq);spin_unlock_irq(&(kbd-lock);4、 实现键盘驱动设备打开操作函数static int Emdoor_kbd_open(struct inode *inode, struct file *filp)int ret;printk(KERN_EMERG Emdoor_kbd_open!n);KBD_DEV * kbd;kbd =(KBD_DEV *) kmalloc(sizeof(KBD_DEV ), GFP_KERNEL);KPC=KPC_ASACT | (326) | (723 ) | KPC_IMKP | KPC_MS6 | KPC_MS5 |KPC_MS4 | KPC_MS3 | KPC_MS2 | KPC_MS1 | KPC_MS0 | KPC_ME |KPC_MIE | (7wq);pxa_gpio_mode(94 | GPIO_ALT_FN_1_IN);/KP_DKINpxa_gpio_mode(95 | GPIO_ALT_FN_1_IN);/KP_DKINpxa_gpio_mode(98 | GPIO_ALT_FN_1_IN);pxa_gpio_mode(99 | GPIO_ALT_FN_1_IN);pxa_gpio_mode(100 | GPIO_ALT_FN_1_IN);pxa_gpio_mode(101 | GPIO_ALT_FN_1_IN);pxa_gpio_mode(102 | GPIO_ALT_FN_1_IN);pxa_gpio_mode(103 | GPIO_ALT_FN_2_OUT);/KP_MKOUTpxa_gpio_mode(104 | GPIO_ALT_FN_2_OUT);/KP_MKOUTpxa_gpio_mode(105 | GPIO_ALT_FN_2_OUT);/KP_MKOUTpxa_gpio_mode(108 | GPIO_ALT_FN_2_OUT);/KP_MKOUTkbd-kbd_status=KEYVALUE_NO;filp-private_data=kbd;ret = request_irq(IRQ_KEYPAD, Emdoor_isr_kbd, SA_INTERRUPT, DEVICE_NAME, kbd);if (ret) printk(KERN_EMERG Interrupt init=%x!n,ret); return ret;return 0;5、 实现键盘驱动select和poll操作函数static unsigned int Emdoor_kbd_poll(struct file *filp,struct poll_table_struct *wait)printk(KERN_EMERG Emdoor_kbd_poll!n);KBD_DEV * kbd=filp-private_data;poll_wait(filp,&(kbd-wq),wait);return (kbd-kbd_status=KEYVALUE_HAVE) ? (POLLIN|POLLRDNORM): 0 ;static int Emdoor_kbd_release(struct inode *inode, struct file *filp) printk(KERN_EMERG Emdoor_kbd_release!n);KBD_DEV * kbd = filp-private_data;KPC=0x0;Emdoor_kbd_fasync(-1, filp, 0);kfree(kbd );free_irq(IRQ_KEYPAD, kbd);return 0;6、 实现键盘驱动非阻塞访问操作函数static int Emdoor_kbd_fasync(int fd, struct file * file, int mode)return fasync_helper(fd, file, mode, &(fasync) );7、 键盘驱动文件结构体定义static struct file_operations Keypad_fops = open:Emdoor_kbd_open,read:Emdoor_kbd_read,release:Emdoor_kbd_release,poll:Emdoor_kbd_poll,fasync:Emdoor_kbd_fasync,owner:THIS_MODULE,;8、 键盘驱动初始化函数定义static int _init Emdoor_kbd_init(void)printk(KERN_EMERG Emdoor_kpd initializedn);int ret;ret = register_chrdev(62, DEVICE_NAME, &Keypad_fops);if (ret 0) printk(DEVICE_NAME cant get major numbern);return ret;free_irq(IRQ_KEYPAD,NULL);udelay(10);return 0;9、 键盘驱动退出函数定义static void _exit Emdoor_kbd_exit(void)printk(KERN_EMERG Emdoor_kpd exitn);unregister_chrdev(62, DEVICE_NAME);module_init(Emdoor_kbd_init);module_exit(Emdoor_kbd_exit);MODULE_AUTHOR(B);MODULE_DESCRIPTION(This is a Keypad driver demo); 第二步: 利用vi编辑器，编写一个用于编译Keypad驱动的Makefile# Makefile for the Keypad. #CFLAGS +=$(DEBFLAGS) -Wallifneq ($(KERNELRELEASE),)obj-m :=Keypad.oelseKERNELDIR ?=/root/work/linux-2.6.9PWD :=$(shell pwd)ALL:$(MAKE) $(CFLAGS) -C $(KERNELDIR) M=$(PWD) modulesendifclean:rm -fr *.o *.ko * core .depend .*.cmd *.mod.c .tmp_versions第三步: 运行make编译命令，用ls命令查看编译后的结果，在该目录中应生成Keypad.ko模块文件，利用file命令查看Keypad.ko文件的格式，应为ARM格式的ELF文件。【图8-2-1】第四步: 利用vi编辑器在test目录下编译测试驱动的Keypad_test.c源文件。#include #include #include #include #include #include #include int fd, fd_max;fd_set readfds;void handle();int main(void) fd=-1; long oflags; fd= open(/dev/emdoor_kbd,O_RDWR); if(fd0) printf(Keypad device open success!n); else printf(Keypad device open fail!n); return 0; fd_max = fd; signal(SIGIO, &handle); fcntl(fd, F_SETOWN, getpid(); oflags = fcntl(fd, F_GETFL); fcntl(fd, F_SETFL, oflags | FASYNC); printf(Please press the keypad:n); while(1) ; void handle() char buf=0; FD_ZERO(&readfds); FD_SET(fd, &readfds); select(fd_max + 1, &readfds, NULL, NULL, NULL); if ( FD_ISSET(fd, &readfds) read(fd, &buf, sizeof(char); printf(Scancode is 0x%08xn, buf); 第五步: 利用vi编辑器，编写一个用于编译Keypad_test.c的Makefile文件；其中CC = arm-linux-gcc为交叉编译工具所在的路径位置，INCLUDEDIR = /usr/local/xscalev1/arm-linux/include为头文件所在的路径 # Makefile for Keypad test#CC = /opt/xscalev1/bin/arm-linux-gccINCLUDEDIR = /usr/local/xscalev1/arm-linux/includeCFLAGS = -Wall -I. -I$(INCLUDEDIR)TARGET_TEST=Keypad_testOBJ_TEST = $(TARGET_TEST)SOURCE_TEST = $(TARGET_TEST).cALL: $(CC) $(CFLAGS) -o $(OBJ_TEST) $(SOURCE_TEST)clean:rm -rf $(OBJ_TEST)第六步: 运行mak