驱动
驱动
#include <linux/kernel.h> #include <linux/module.h> #include <linux/miscdevice.h> #include <linux/fs.h> #include <linux/types.h> #include <linux/moduleparam.h> #include <linux/slab.h> #include <linux/ioctl.h> #include <linux/cdev.h> #include <linux/delay.h> #include <mach/gpio.h> #include <mach/regs-gpio.h> #include <plat/gpio-cfg.h> #define DEVICE_NAME "leds" static int led_gpios[] = { S5PV210_GPH2(0), S5PV210_GPH2(1), S5PV210_GPH2(2), S5PV210_GPH2(3), S5PV210_GPH3(0), S5PV210_GPH3(1), S5PV210_GPH3(2), S5PV210_GPH3(3), }; #define LED_NUM ARRAY_SIZE(led_gpios) static long mini210_leds_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { switch(cmd) { case 0: case 1: if (arg > LED_NUM) { return -EINVAL; } gpio_set_value(led_gpios[arg], !cmd); printk(DEVICE_NAME": %d %d\n", arg, cmd); break; default: return -EINVAL; } return 0; } static struct file_operations mini210_led_dev_fops = { .owner = THIS_MODULE, .unlocked_ioctl = mini210_leds_ioctl, }; static struct miscdevice mini210_led_dev = { .minor = MISC_DYNAMIC_MINOR, .name = DEVICE_NAME, .fops = &mini210_led_dev_fops, }; static int __init mini210_led_dev_init(void) { int ret; int i; for (i = 0; i < LED_NUM; i++) { ret = gpio_request(led_gpios[i], "LED"); if (ret) { printk("%s: request GPIO %d for LED failed!, ret = %d\n", DEVICE_NAME, led_gpios[i], ret); return ret; } if (!ret) { printk("%s: request GPIO %d for LED success!, ret = %d\n", DEVICE_NAME, led_gpios[i], ret); } s3c_gpio_cfgpin(led_gpios[i], S3C_GPIO_OUTPUT); gpio_set_value(led_gpios[i], 1); } ret = misc_register(&mini210_led_dev); printk(DEVICE_NAME"\tinitialized\n"); return ret; } static void __exit mini210_led_dev_exit(void) { int i; for (i = 0; i < LED_NUM; i++) { gpio_free(led_gpios[i]); } misc_deregister(&mini210_led_dev); } module_init(mini210_led_dev_init); module_exit(mini210_led_dev_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("FriendlyARM Inc.");
测试文件
#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/ioctl.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> int main(int argc, char **argv) { int on; int led_no; int fd; if (argc != 3 || sscanf(argv[1], "%d", &led_no) != 1 || sscanf(argv[2],"%d", &on) != 1 || on < 0 || on > 1 || led_no < 0 || led_no > 7) { fprintf(stderr, "Usage: leds 0|1 led_no \n"); exit(1); } fd = open("/dev/leds0", 0); if (fd < 0) { fd = open("/dev/leds", 0); } if (fd < 0) { perror("open device leds"); exit(1); } ioctl(fd, on, led_no); close(fd); return 0; }
Makefile
# ---------------------------------------------------------------------------- # Makefile for building tapp # # Copyright 2010 FriendlyARM (http://www.arm9.net/) # ifndef DESTDIR DESTDIR ?= /work/rootfile/rootfs endif CFLAGS = -Wall -O2 CC = arm-none-linux-gnueabi-gcc INSTALL = install TARGET = led all: $(TARGET) led: led.c $(CC) $(CFLAGS) $< -o $@ install: $(TARGET) $(INSTALL) $^ $(DESTDIR) clean distclean: rm -rf *.o $(TARGET) # ---------------------------------------------------------------------------- .PHONY: $(PHONY) install clean distclean # End of file # vim: syntax=make