rk3399 gpio驱动移植

Chip Platform Rockchip
1

之前开发了rk3288，移植了gpio驱动，并能成功移植。现在我用同样的gpio驱动源码，移植到rk3399里，发现一调用ioctl就会造成安卓死机重启，这是什么原因？
二楼附上gpio驱动源码：

2

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/leds.h>
#include <linux/io.h>
#include <linux/semaphore.h>
#include <linux/kernel.h>
#include <linux/cdev.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include<linux/gpio.h>
#include <linux/pinctrl/consumer.h>
#include <asm/delay.h>

#define ENBLK 149
#define DEFAULT_VALUE 255

#define GPIO_IOC_MAGIC ‘G’
#define IOCTL_GPIO_SETOUTPUT _IOW(GPIO_IOC_MAGIC, 0, int)
#define IOCTL_GPIO_SETINPUT _IOW(GPIO_IOC_MAGIC, 1, int)
#define IOCTL_GPIO_SETVALUE _IOW(GPIO_IOC_MAGIC, 2, int)
#define IOCTL_GPIO_GETVALUE _IOR(GPIO_IOC_MAGIC, 3, int)
//#define IOCTL_GPIO_BKLTENABLE _IOR(GPIO_IOC_MAGIC, 4, int)
#define GPIO_IOC_MAXNR 3

struct rk_gpio_arg{
int pin;
int data;
};

struct rk_gpio_node{
int pin;
struct rk_gpio_node *next;
};

static int gpio_major = 0;
static int gpio_minor = 0;
static struct class *gpio_class;
static struct device *rk_dev;
static struct cdev gpio_cdev;
static struct rk_gpio_node *head;

static int is_required(int pinnum)
{
struct rk_gpio_node *pnode = head->next;
struct rk_gpio_node *rnode = head;

while(pnode != NULL)
{
	if(pnode->pin == pinnum)
		return 0;
	else
	{
		rnode = pnode;
		pnode = pnode->next;
	}
}
printk("New GPIO Registered!\n");
pnode = (struct rk_gpio_node *)kmalloc(sizeof(struct rk_gpio_node), GFP_KERNEL);
if(pnode != NULL)
{
	rnode->next = pnode;
	pnode->pin = pinnum;
	pnode->next = NULL;
}
else
	printk("Can't Kmalloc...\n");

return 1;

}

static int gpio_open(struct inode *inode,struct file *filp)
{
return 0;
}

static int gpio_release(struct inode *inode,struct file *filp)
{
return 0;
}

static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
int err = 0;

struct rk_gpio_arg *parg = (struct rk_gpio_arg *)arg;

if(is_required(parg->pin))
{
	err = gpio_request(parg->pin, "rk_gpio");
	if(err != 0)
	{
		printk("Can't request this gpio!\n");
		gpio_free(parg->pin);
	}
}
switch (cmd) {
case IOCTL_GPIO_SETOUTPUT:

		gpio_direction_output(parg->pin, parg->data);
	break;
case IOCTL_GPIO_SETINPUT:

		gpio_direction_input(parg->pin);
	break;
case IOCTL_GPIO_SETVALUE:

		gpio_set_value(parg->pin, parg->data);
	break;
case IOCTL_GPIO_GETVALUE:

		parg->data = gpio_get_value(parg->pin) ? 1 : 0;
	break;
default :
		printk(KERN_WARNING "Unsuported Ioctl Cmd\n");
}

return 0;

}

struct file_operations gpio_fops = {
.owner = THIS_MODULE,
.open = gpio_open,
//change by louhn
.unlocked_ioctl = gpio_ioctl,
//.compat_ioctl = gpio_ioctl,
.release = gpio_release,
};

static int __init rk_gpio_init(void)
{
int result;
dev_t dev = 0;

result = alloc_chrdev_region(&dev, gpio_minor, 1,"rk_gpio");
gpio_major = MAJOR(dev);
if (result < 0) {
	printk(KERN_WARNING "Can't get major %d\n", gpio_major);
	return result;
}
printk(" GPIO Driver Registered.\n");

cdev_init(&gpio_cdev, &gpio_fops);
gpio_cdev.owner = THIS_MODULE;
gpio_cdev.ops = &gpio_fops;
result = cdev_add (&gpio_cdev, dev, 1);

gpio_class = class_create(THIS_MODULE, "rk_gpio");
if (IS_ERR(gpio_class)) {
    	printk(KERN_WARNING "Class_create faild\n");
	cdev_del(&gpio_cdev);
	unregister_chrdev_region(dev, 0);
	return result;
}
rk_dev = device_create(gpio_class, NULL, dev, 0, "rk_gpio");

head = (struct rk_gpio_node *)kmalloc(sizeof(struct rk_gpio_node), GFP_KERNEL);
if(head == NULL)
{
	return -1;
}
else
{
    head->pin = 0;
    head->next = NULL;
}
return 0;

}

static void __exit rk_gpio_exit(void)
{
dev_t dev = 0;
struct rk_gpio_node *pnode = head->next;
struct rk_gpio_node *rnode = NULL;

while(pnode != NULL )
{
	rnode = pnode->next;
    kfree(pnode);
    pnode = rnode;
}
kfree(head);

dev = MKDEV(gpio_major, gpio_minor);

class_unregister(gpio_class);
class_destroy(gpio_class);
unregister_chrdev_region(dev, 0);
cdev_del(&gpio_cdev);

}

module_init(rk_gpio_init);
module_exit(rk_gpio_exit);

MODULE_DESCRIPTION(“Driver for rockchip GPIO”);
MODULE_AUTHOR(“hzmct.com”);
MODULE_LICENSE(“GPL”);

3

我如果使用.compat_ioctl = gpio_ioctl,就会造成安卓四级重启

4

找到原因了，估计是4.4的内核添加了防护的机制在 struct rk_gpio_arg *parg = (struct rk_gpio_arg *)arg; 这里不能直接赋值，而是应该使用copy_from_user函数