first sample

03_day/Makefile

@@ -0,0 +1,10 @@
+obj-m = blocking_dev.o
+
+KDIR = /usr/src/tegra
+PWD  = $(shell pwd) 
+
+default:
+	make -C  $(KDIR) SUBDIRS=$(PWD) modules
+
+clean:
+	make -C  $(KDIR) SUBDIRS=$(PWD) clean

03_day/blocking_dev.c

@@ -0,0 +1,75 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>  //misc_register
+#include <linux/wait.h>
+#include <asm/uaccess.h>
+#include <linux/interrupt.h>
+
+static int temp;
+static DECLARE_WAIT_QUEUE_HEAD(my_wait);
+
+int my_open (struct inode *inode, struct file *filp)
+{
+	temp = -999;
+	printk("my_open()\n");
+	return 0;
+}
+int my_close(struct inode *inode, struct file *filp)
+{
+	printk("my_close()\n");
+	return 0;
+}
+
+irqreturn_t my_handler(int irq, void *id)
+{
+	printk("my_handler()\n");
+	temp=23;
+	wake_up_interruptible(&my_wait);
+	return IRQ_HANDLED;
+}
+
+ssize_t my_read (struct file *filp, char __user *buff, size_t size, 
+		         loff_t *off)
+{
+	printk("my_read()\n");
+	if( temp == -999 )
+		interruptible_sleep_on(&my_wait);
+	put_user( temp, (int*)buff );
+	return 4;
+}
+
+static  struct file_operations fops = 
+{
+	.open    = my_open,
+	.release = my_close,
+	.read    = my_read,
+};
+
+static struct miscdevice  misc =
+{
+	.minor = MISC_DYNAMIC_MINOR, 
+	.name  = "mydev", 
+	.fops  = &fops, 
+};
+
+int my_init(void)
+{
+	int ret;
+	unsigned long flags=IRQF_SHARED;
+	misc_register( &misc );
+	flags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+	ret = request_irq(342, my_handler, flags, "MY_INT", my_handler);
+	return 0;
+}
+
+void my_exit(void)
+{
+	free_irq( 342, my_handler);
+	misc_deregister( &misc );
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/ioctl_dev.c

@@ -0,0 +1,99 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>  //misc_register
+#include <asm/ioctl.h>
+#include <asm/uaccess.h>
+
+int my_open (struct inode *inode, struct file *filp)
+{
+	printk("my_open()\n");
+	return 0;
+}
+int my_close(struct inode *inode, struct file *filp)
+{
+	printk("my_close()\n");
+	return 0;
+}
+//#define BINDER_WRITE_READ		_IOWR('b', 1, struct binder_write_read)
+#define  LED_RATIO   _IOW( 'm', 1, int )
+
+static int ratio;
+
+long my_ioctl(struct file *filp, unsigned int cmd, unsigned long opt)
+{
+	unsigned int size;
+	int ret;
+	printk("my_ioctl()\n");
+
+	size = _IOC_SIZE(cmd);
+
+	switch( cmd )
+	{
+		case LED_RATIO:  
+			if( size != sizeof(int))
+				return -EINVAL;
+
+			ret = copy_from_user( &ratio, (void*)opt, size); 
+		    printk("LED_RATIO, ratio=%d\n", ratio );
+			break;
+	}
+			
+	return 0;
+}
+/*
+//#define BINDER_WRITE_READ		_IOWR('b', 1, struct binder_write_read)
+#define  LED_RATIO   _IO( 'm', 1 )
+static int ratio;
+
+long my_ioctl(struct file *filp, unsigned int cmd, unsigned long opt)
+{
+	printk("my_ioctl()\n");
+
+	if( _IOC_TYPE(cmd) != 'm' )
+		return -EINVAL;
+
+	if( _IOC_NR(cmd) != 1 )
+		return -EINVAL;
+
+	switch( cmd )
+	{
+		case LED_RATIO:  ratio = 128; 
+						 printk("LED_RATIO, ratio=%d\n", ratio );
+						 break;
+	}
+			
+	return 0;
+}
+*/
+
+static  struct file_operations fops = 
+{
+	.open            = my_open,
+	.release         = my_close,
+	.unlocked_ioctl  = my_ioctl,
+	.compat_ioctl    = my_ioctl,
+};
+
+static struct miscdevice  misc =
+{
+	.minor = MISC_DYNAMIC_MINOR, 
+	.name  = "mydev", 
+	.fops  = &fops, 
+};
+
+int my_init(void)
+{
+	misc_register( &misc );
+	return 0;
+}
+
+void my_exit(void)
+{
+	misc_deregister( &misc );
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/jni/Android.mk

@@ -0,0 +1,8 @@
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+LOCAL_CFLAGS    := -fPIE
+LOCAL_LDFLAGS   := -fPIE -pie
+LOCAL_MODULE    := myapp
+LOCAL_SRC_FILES := blocking_app.c
+include $(BUILD_EXECUTABLE)
+

03_day/jni/ioctl_app.c

@@ -0,0 +1,52 @@
+#if 1
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#define  LED_RATIO   _IOW( 'm', 1 , int)
+
+int main()
+{
+	int fd, ret;
+	int ratio;
+	char buff[10];
+	printf("밝기 입력( 0-255 ) : ");
+	scanf("%d", &ratio );
+	fd = open( "/dev/mydev", O_RDONLY );
+	ret = ioctl(fd, LED_RATIO, &ratio);
+	if( ret < 0 )
+	{
+		printf("ret=%d, errno=%d\n", ret, errno );
+		return 0;
+	}
+	close(fd);
+	return 0;
+}
+#endif
+#if 0
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#define  LED_RATIO   _IO( 'm', 1 )
+
+int main()
+{
+	int fd, ret;
+	char buff[10];
+	fd = open( "/dev/mydev", O_RDONLY );
+	ret = ioctl(fd, LED_RATIO);
+	if( ret < 0 )
+	{
+		printf("ret=%d, errno=%d\n", ret, errno );
+		return 0;
+	}
+	close(fd);
+	return 0;
+}
+#endif
+

03_day/jni/mmap_app.c

@@ -0,0 +1,21 @@
+#if 1
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+
+int main()
+{
+	int fd;
+	char *p;
+	fd = open("/dev/mydev", O_RDWR );
+	p = mmap(0, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	strcpy( p , "hello world\n");
+	printf("%s\n", p );
+	munmap(p, 4096);
+	close(fd);
+	return 0;
+}
+
+#endif
+

03_day/jni/myapp.c

@@ -0,0 +1,10 @@
+#include <fcntl.h>
+int main()
+{
+	int fd;
+	fd = open( "/sys/devices/virtual/misc/mydev/uevent", O_WRONLY );
+	write( fd, "add\n", 4 );
+	close(fd);
+	return 0;
+}
+

03_day/jni/poll_app.c

@@ -0,0 +1,59 @@
+#if 1
+#include <stdio.h>
+#include <poll.h>
+#include <fcntl.h>
+
+int main()
+{
+	int fd, ret;
+	int temp;
+	char buff[1024];
+	struct pollfd fds[2];
+	fd = open( "/dev/mydev", O_RDONLY );
+	fds[0].fd = 0 ;
+	fds[0].events = POLLIN;
+	fds[1].fd = fd ;
+	fds[1].events = POLLIN;
+
+	poll( fds, 2, -1 );
+
+	if( fds[0].revents & POLLIN )
+	{
+		read( 0, buff, sizeof buff );
+		buff[ret-1] = 0;
+		printf("buff=%s\n", buff );
+	}
+	if( fds[1].revents & POLLIN )
+	{
+		read( fd, &temp, sizeof temp );
+		printf("temp=%d\n", temp );
+	}
+	close(fd);
+	return 0;
+}
+#endif
+#if 0
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#define  LED_RATIO   _IO( 'm', 1 )
+
+int main()
+{
+	int fd, ret;
+	char buff[10];
+	fd = open( "/dev/mydev", O_RDONLY );
+	ret = ioctl(fd, LED_RATIO);
+	if( ret < 0 )
+	{
+		printf("ret=%d, errno=%d\n", ret, errno );
+		return 0;
+	}
+	close(fd);
+	return 0;
+}
+#endif
+

03_day/jni/rdwr_app.c

@@ -0,0 +1,57 @@
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+int main()
+{
+	int fd, ret;
+	char buff[10];
+	fd = open( "/dev/mydev", O_RDONLY );
+	ret = read( fd, buff, sizeof buff );
+	buff[ret] = 0;
+	printf( "buff[%s], ret=%d\n", buff, ret );
+	close(fd);
+	return 0;
+}
+/*
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+int main()
+{
+	int fd, ret;
+	int temp;
+	fd = open( "/dev/mydev", O_RDONLY );
+	ret = read( fd, &temp, sizeof temp );
+	printf( "temp=%d, ret=%d\n", temp, ret );
+	close(fd);
+	return 0;
+}
+*/
+
+/*
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+int main()
+{
+	int fd, ret;
+	char buff[] = "LED_ON";
+	fd = open( "/dev/mydev", O_WRONLY );
+	ret = write( fd, buff, strlen(buff) );
+	printf( "ret=%d\n", ret );
+	close(fd);
+	return 0;
+}
+*/
+/*
+#include <fcntl.h>
+int main()
+{
+	int fd;
+	int flag=128;
+	fd = open( "/dev/mydev", O_WRONLY );
+	write( fd, &flag, sizeof flag );
+	close(fd);
+	return 0;
+}
+*/

03_day/kernel_file.c

@@ -0,0 +1,29 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/gfp.h>
+// /data/aaa
+int my_init(void) {
+	char *buff;
+	struct file *filp;
+	int ret;
+	filp = filp_open( "/data/bbb", O_WRONLY|O_TRUNC|O_CREAT, 0666 );
+	if( filp == 0 )
+		return 0;
+	buff = (char*)__get_free_pages( GFP_KERNEL, 0 );
+	strcpy(buff, "hello world");
+	ret = kernel_write( filp, buff, strlen(buff), 0 );
+	printk("ret=%d\n", ret );
+	free_pages( (unsigned long)buff, 0 );
+	filp_close( filp, 0 );
+	return 0;
+}
+
+void my_exit(void)
+{
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/mmap.c

@@ -0,0 +1,34 @@
+#if 1
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+int main()
+{
+	int fd;
+	char *p;
+	printf("main=%p\n", main);
+	fd = open("aaa", O_RDWR | O_TRUNC | O_CREAT , 0666 );
+	ftruncate(fd, 1024);
+	p = mmap(0, 1024, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	strcpy( p , "hello world\n");
+	//printf("%s\n", p );
+	munmap(p, 1024);
+	close(fd);
+	return 0;
+}
+#endif
+
+#if 0
+#include <fcntl.h>
+int main()
+{
+	//mmap();
+
+	int fd;
+	fd = open("aaa", O_WRONLY | O_TRUNC | O_CREAT , 0666 );
+	write( fd, "hello world", 11 );
+	close(fd);
+	return 0;
+}
+#endif

03_day/mmap_dev.c

@@ -0,0 +1,60 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>  //misc_register
+#include <linux/mm_types.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+
+int my_open (struct inode *inode, struct file *filp)
+{
+	printk("my_open()\n");
+	return 0;
+}
+int my_close(struct inode *inode, struct file *filp)
+{
+	printk("my_close()\n");
+	return 0;
+}
+
+int my_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	unsigned long pfn;
+	unsigned long page;
+	printk("my_mmap()\n");
+	page = __get_free_pages( GFP_KERNEL, 0 );
+	pfn = __pa( page );
+    remap_pfn_range(vma, vma->vm_start, 
+			        pfn>>12, 1<<12, vma->vm_page_prot);
+	return 0;
+}
+
+static  struct file_operations fops = 
+{
+	.open    = my_open,
+	.release = my_close,
+	.mmap    = my_mmap,
+};
+
+static struct miscdevice  misc =
+{
+	.minor = MISC_DYNAMIC_MINOR, 
+	.name  = "mydev", 
+	.fops  = &fops, 
+};
+
+int my_init(void)
+{
+	misc_register( &misc );
+	return 0;
+}
+
+void my_exit(void)
+{
+	misc_deregister( &misc );
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/my_int.c

@@ -0,0 +1,28 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+
+irqreturn_t my_handler(int irq, void *id)
+{
+	printk("my_handler()\n");
+	return IRQ_HANDLED;
+}
+
+int my_init(void)
+{
+	int ret;
+	unsigned long flags=IRQF_SHARED;
+	flags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+	ret = request_irq(342, my_handler, flags, "MY_INT", my_handler);
+	return 0;
+}
+
+void my_exit(void)
+{
+	free_irq( 342, my_handler);
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/my_memory.c

@@ -0,0 +1,56 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+struct my_struct
+{
+	char name[20];
+	int  id;
+};
+
+int my_init(void)
+{
+	char *p;
+	struct my_struct *task;
+	struct kmem_cache *my_struct_cachep;
+	p = (char*)__get_free_pages( GFP_KERNEL, 0 );
+	p[4095] = 'x';
+	printk("%c\n", p[4095]);
+	free_pages((unsigned long)p, 0);
+
+	p = (char*)kmalloc( 64, GFP_KERNEL);
+	p[63] = 'x';
+	printk("%c\n", p[63]);
+	kfree(p);
+
+#define L1_CACHE_SHIFT		6
+#define L1_CACHE_BYTES		(1 << L1_CACHE_SHIFT)
+#define ARCH_MIN_TASKALIGN	L1_CACHE_BYTES
+
+	my_struct_cachep =
+		kmem_cache_create("my_struct", sizeof(struct my_struct),
+			ARCH_MIN_TASKALIGN, SLAB_PANIC | SLAB_NOTRACK, NULL);
+	task = kmem_cache_alloc( my_struct_cachep, GFP_KERNEL);
+	strcpy( task->name, "kji");
+	task->id = 1234;
+	printk("%s, %d\n", task->name, task->id);
+	kmem_cache_free( my_struct_cachep, task);
+	kmem_cache_destroy( my_struct_cachep );
+
+	p = vmalloc( 8192 * 1024 );
+	p[8192 * 1024-1] = 'x';
+	printk("%c\n", p[8192 * 1024-1] );
+	vfree( p );
+	return 0;
+}
+
+void my_exit(void)
+{
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/poll_1.c

@@ -0,0 +1,74 @@
+#if 1
+#include <fcntl.h>
+#include <stdio.h>
+#include <poll.h>
+int main()
+{
+	char buff[1024];
+	int ret;
+	int fd;
+	struct pollfd fds[2];
+	// mkfifo myfifo
+	fd = open("myfifo", O_RDWR );
+	while(1)
+	{
+		fds[0].fd = 0;
+		fds[0].events = POLLIN;
+		fds[1].fd = fd;
+		fds[1].events = POLLIN;
+		poll( fds, 2, -1);
+		if( fds[0].revents & POLLIN )
+		{
+			ret = read(0, buff, sizeof buff );
+			buff[ret-1] = 0;
+			printf("키보드 [%s]\n", buff );
+		}
+
+		if( fds[1].revents & POLLIN )
+		{
+			ret = read(fd, buff, sizeof buff );
+			buff[ret-1] = 0;
+			printf("myfifo [%s]\n", buff );
+		}
+	}
+	close(fd);
+	return 0;
+}
+#endif
+#if 0
+#include <fcntl.h>
+#include <stdio.h>
+int main()
+{
+	char buff[1024];
+	int ret;
+	int fd;
+	// mkfifo myfifo
+	fd = open("myfifo", O_RDWR );
+	while(1)
+	{
+		ret = read(0, buff, sizeof buff );
+		buff[ret-1] = 0;
+		printf("키보드 [%s]\n", buff );
+
+		ret = read(fd, buff, sizeof buff );
+		buff[ret-1] = 0;
+		printf("myfifo [%s]\n", buff );
+	}
+	close(fd);
+	return 0;
+}
+#endif
+
+
+#if 0
+#include <fcntl.h>
+int main()
+{
+	char buff[1024];
+	int ret;
+	ret = read(0, buff, sizeof buff );
+	write( 1, buff, ret );
+	return 0;
+}
+#endif

03_day/poll_dev.c

@@ -0,0 +1,87 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>  //misc_register
+#include <linux/wait.h>
+#include <linux/timer.h>
+#include <asm/uaccess.h>
+#include <linux/poll.h>
+
+static int temp;
+static DECLARE_WAIT_QUEUE_HEAD(my_wait);
+static struct timer_list timer;
+
+void my_function(unsigned long data)
+{
+	printk("my_function(%lu)\n", data );
+	temp = 28;
+	wake_up_interruptible( &my_wait );
+}
+int my_open (struct inode *inode, struct file *filp)
+{
+	init_timer( &timer );
+	timer.expires  = jiffies + 3*HZ;
+	timer.function = my_function;
+	timer.data     = 0;
+	add_timer( &timer );
+	temp = -999;
+	printk("my_open()\n");
+	return 0;
+}
+int my_close(struct inode *inode, struct file *filp)
+{
+	printk("my_close()\n");
+	return 0;
+}
+
+
+unsigned int my_poll(struct file *filp, struct poll_table_struct *table)
+{
+	unsigned int mask=0;
+	printk("my_poll()\n");
+
+	poll_wait(filp, &my_wait, table);
+	if( temp != -999 )
+		mask = POLLIN;
+	return mask;
+}
+
+ssize_t my_read (struct file *filp, char __user *buff, size_t size, 
+		         loff_t *off)
+{
+	printk("my_read()\n");
+	put_user( temp, (int*)buff );
+	return 4;
+}
+
+static  struct file_operations fops = 
+{
+	.open    = my_open,
+	.release = my_close,
+	.poll    = my_poll, 
+	.read    = my_read,
+};
+
+static struct miscdevice  misc =
+{
+	.minor = MISC_DYNAMIC_MINOR, 
+	.name  = "mydev", 
+	.fops  = &fops, 
+};
+
+int my_init(void)
+{
+	misc_register( &misc );
+	return 0;
+}
+
+void my_exit(void)
+{
+	del_timer( &timer );
+	misc_deregister( &misc );
+}
+
+MODULE_LICENSE("GPL");
+module_init( my_init );
+module_exit( my_exit );
+

03_day/type.c

@@ -0,0 +1,10 @@
+#include <stdio.h>
+int main()
+{
+	int a[4];
+	int *p = a;
+	printf("sizeof(a)     =%lu\n", sizeof(a));
+	printf("sizeof(int[4])=%lu\n", sizeof(int[4]));
+	printf("sizeof(p)     =%lu\n", sizeof(p));
+	printf("sizeof(int*)  =%lu\n", sizeof(int*));
+}