S5PC100上 LED与S3C2410上 LED 驱动对比

 

S5PC100上 LED与S3C2410上 LED 驱动对比

作者：陈刚, 华清远见嵌入式学院 讲师。

芯片手册，电路图区别

S5PC100 芯片手册片段：

FS_S5PC100A LED电路图：

S3C2410芯片手册片段：

FS2410 LED电路图

由此资料可知S5PC100 相对s3c2410，I/O增加不少！

使用相同版本的Linux，字符驱动框架相同，只是控制的寄存器不同！S5PC100主要使用GPG3CON（0xE03001C0），GPG3DAT（0xE03001C4） 两个寄存器。s3c2410 GPFCON（0x56000050），GPFDAT（0x56000054） 两个寄存器。

FS_S5PC100 LED灯 Linux驱动

#include
        #include
        #include

#include /* printk() */
        #include /* kmalloc() */
        #include /* everything... */
        #include /* error codes */
        #include /* size_t */
        #include
        #include
        #include
        #include
        #include
        #include
        #include

#define pGPG3CON 0xE03001C0 （GPFCON 0x56000050）
         #define pGPG3DAT 0xE03001C4 （GPFDAT 0x56000054）

static void *vGPG3CON , *vGPG3DAT;

#define GPG3CON (*(volatile unsigned int *) vGPG3CON)
        #define GPG3DAT (*(volatile unsigned int *) vGPG3DAT)
         #define LED_ON 0x4800
        #define LED_OFF 0x4801

static int simple_major = 250;
        module_param(simple_major, int, 0);
        MODULE_AUTHOR("farsight");
        MODULE_LICENSE("Dual BSD/GPL");

//static int flag = 0;

/*
        * Open the device; in fact, there's nothing to do here.
        */
        int simple_open (struct inode *inode, struct file *filp)
        {
                vGPG3CON=ioremap(pGPG3CON,0x10);
                 vGPG3DAT=vGPG3CON+0x04;
                GPG3CON=0x1111; （GPFCON= 0x5500）
                GPG3DAT=0xff;
                return 0;
        }

ssize_t simple_read(struct file *file, char __user *buff, size_t count, loff_t *offp)
        {
                return 0;
        }

ssize_t simple_write(struct file *file, const char __user *buff, size_t count, loff_t *offp)
        {
                return 0;
        }

void led_off( void )
        {
                GPG3DAT=GPG3DAT|(1<<2);
                //printk("stop led\n");
        }
        void led_on( void )

{
                GPG3DAT=GPG3DAT&(~(1<<2));
                //printk("start led\n");
        }

static int simple_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
        {
                switch ( cmd )
                {
                        case LED_ON:
                        {
                                led_on();
                                break;
                        }
                        case LED_OFF:
                        {
                                led_off();
                                break;
                        }
                        default:
                        {
                                break;
                        }
                }
                return 0;
        }

static int simple_release(struct inode *node, struct file *file)
        {
                return 0;
        }

/*
        * Set up the cdev structure for a device.
        */
        static void simple_setup_cdev(struct cdev *dev, int minor,struct file_operations *fops)
        {
                int err, devno = MKDEV(simple_major, minor);

        cdev_init(dev, fops);
                dev->owner = THIS_MODULE;
                dev->ops = fops;
                err = cdev_add (dev, devno, 1);
                /* Fail gracefully if need be */
                if (err)
                        printk (KERN_NOTICE "Error %d adding simple%d", err, minor);
        }

/*
        * Our various sub-devices.
        */
        /* Device 0 uses remap_pfn_range */
        static struct file_operations simple_remap_ops = {
                .owner = THIS_MODULE,
                .open = simple_open,
                .release = simple_release,
                .read = simple_read,
                .write = simple_write,
                .ioctl = simple_ioctl,
        };

/*
        * We export two simple devices. There's no need for us to maintain any
        * special housekeeping info, so we just deal with raw cdevs.
        */
        static struct cdev SimpleDevs;

/*
        * Module housekeeping.
        */
        static struct class *my_class;
        static int simple_init(void)
        {
                int result;
                dev_t dev = MKDEV(simple_major, 0);

        /* Figure out our device number. */
                if (simple_major)
                        result = register_chrdev_region(dev, 1, "simple");
                else {
                        result = alloc_chrdev_region(&dev, 0, 1, "simple");
                        simple_major = MAJOR(dev);
                }
                if (result < 0) {
                        printk(KERN_WARNING "simple: unable to get major %d\n", simple_major);
                        return result;
                }
                if (simple_major == 0)
                        simple_major = result;

        /* Now set up two cdevs. */
                simple_setup_cdev(&SimpleDevs, 0, &simple_remap_ops);
                printk("simple device installed, with major %d\n", simple_major);
                my_class= class_create(THIS_MODULE, "simple");
                device_create(my_class, NULL, MKDEV(simple_major, 0),
                NULL, "led");
                return 0;
        }

static void simple_cleanup(void)
        {
                cdev_del(&SimpleDevs);
                unregister_chrdev_region(MKDEV(simple_major, 0), 1);
                device_destroy(my_class,MKDEV(simple_major,0));
                printk("simple device uninstalled\n");
        }

module_init(simple_init);
        module_exit(simple_cleanup);