[deliverable/linux.git] / drivers / i2c / i2c-dev.c

/*
    i2c-dev.c - i2c-bus driver, char device interface  

    Copyright (C) 1995-97 Simon G. Vogl
    Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
    Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/* Note that this is a complete rewrite of Simon Vogl's i2c-dev module.
   But I have used so much of his original code and ideas that it seems
   only fair to recognize him as co-author -- Frodo */

/* The I2C_RDWR ioctl code is written by Kolja Waschk <waschk@telos.de> */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/i2c-dev.h>
#include <linux/platform_device.h>
#include <asm/uaccess.h>

static struct i2c_client i2cdev_client_template;

struct i2c_dev {
	int minor;
	struct i2c_adapter *adap;
	struct class_device *class_dev;
};
#define to_i2c_dev(d) container_of(d, struct i2c_dev, class_dev)

#define I2C_MINORS	256
static struct i2c_dev *i2c_dev_array[I2C_MINORS];
static DEFINE_SPINLOCK(i2c_dev_array_lock);

static struct i2c_dev *i2c_dev_get_by_minor(unsigned index)
{
	struct i2c_dev *i2c_dev;

	spin_lock(&i2c_dev_array_lock);
	i2c_dev = i2c_dev_array[index];
	spin_unlock(&i2c_dev_array_lock);
	return i2c_dev;
}

static struct i2c_dev *i2c_dev_get_by_adapter(struct i2c_adapter *adap)
{
	struct i2c_dev *i2c_dev = NULL;

	spin_lock(&i2c_dev_array_lock);
	if ((i2c_dev_array[adap->nr]) &&
	    (i2c_dev_array[adap->nr]->adap == adap))
		i2c_dev = i2c_dev_array[adap->nr];
	spin_unlock(&i2c_dev_array_lock);
	return i2c_dev;
}

static struct i2c_dev *get_free_i2c_dev(struct i2c_adapter *adap)
{
	struct i2c_dev *i2c_dev;

	i2c_dev = kzalloc(sizeof(*i2c_dev), GFP_KERNEL);
	if (!i2c_dev)
		return ERR_PTR(-ENOMEM);

	spin_lock(&i2c_dev_array_lock);
	if (i2c_dev_array[adap->nr]) {
		spin_unlock(&i2c_dev_array_lock);
		dev_err(&adap->dev, "i2c-dev already has a device assigned to this adapter\n");
		goto error;
	}
	i2c_dev->minor = adap->nr;
	i2c_dev_array[adap->nr] = i2c_dev;
	spin_unlock(&i2c_dev_array_lock);
	return i2c_dev;
error:
	kfree(i2c_dev);
	return ERR_PTR(-ENODEV);
}

static void return_i2c_dev(struct i2c_dev *i2c_dev)
{
	spin_lock(&i2c_dev_array_lock);
	i2c_dev_array[i2c_dev->minor] = NULL;
	spin_unlock(&i2c_dev_array_lock);
}

static ssize_t show_adapter_name(struct class_device *class_dev, char *buf)
{
	struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(class_dev->devt));

	if (!i2c_dev)
		return -ENODEV;
	return sprintf(buf, "%s\n", i2c_dev->adap->name);
}
static CLASS_DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);

static ssize_t i2cdev_read (struct file *file, char __user *buf, size_t count,
                            loff_t *offset)
{
	char *tmp;
	int ret;

	struct i2c_client *client = (struct i2c_client *)file->private_data;

	if (count > 8192)
		count = 8192;

	tmp = kmalloc(count,GFP_KERNEL);
	if (tmp==NULL)
		return -ENOMEM;

	pr_debug("i2c-dev: i2c-%d reading %zd bytes.\n",
		iminor(file->f_dentry->d_inode), count);

	ret = i2c_master_recv(client,tmp,count);
	if (ret >= 0)
		ret = copy_to_user(buf,tmp,count)?-EFAULT:ret;
	kfree(tmp);
	return ret;
}

static ssize_t i2cdev_write (struct file *file, const char __user *buf, size_t count,
                             loff_t *offset)
{
	int ret;
	char *tmp;
	struct i2c_client *client = (struct i2c_client *)file->private_data;

	if (count > 8192)
		count = 8192;

	tmp = kmalloc(count,GFP_KERNEL);
	if (tmp==NULL)
		return -ENOMEM;
	if (copy_from_user(tmp,buf,count)) {
		kfree(tmp);
		return -EFAULT;
	}

	pr_debug("i2c-dev: i2c-%d writing %zd bytes.\n",
		iminor(file->f_dentry->d_inode), count);

	ret = i2c_master_send(client,tmp,count);
	kfree(tmp);
	return ret;
}

static int i2cdev_ioctl(struct inode *inode, struct file *file,
		unsigned int cmd, unsigned long arg)
{
	struct i2c_client *client = (struct i2c_client *)file->private_data;
	struct i2c_rdwr_ioctl_data rdwr_arg;
	struct i2c_smbus_ioctl_data data_arg;
	union i2c_smbus_data temp;
	struct i2c_msg *rdwr_pa;
	u8 __user **data_ptrs;
	int i,datasize,res;
	unsigned long funcs;

	dev_dbg(&client->adapter->dev, "ioctl, cmd=0x%02x, arg=0x%02lx\n",
		cmd, arg);

	switch ( cmd ) {
	case I2C_SLAVE:
	case I2C_SLAVE_FORCE:
		if ((arg > 0x3ff) || 
		    (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
			return -EINVAL;
		if ((cmd == I2C_SLAVE) && i2c_check_addr(client->adapter,arg))
			return -EBUSY;
		client->addr = arg;
		return 0;
	case I2C_TENBIT:
		if (arg)
			client->flags |= I2C_M_TEN;
		else
			client->flags &= ~I2C_M_TEN;
		return 0;
	case I2C_PEC:
		if (arg)
			client->flags |= I2C_CLIENT_PEC;
		else
			client->flags &= ~I2C_CLIENT_PEC;
		return 0;
	case I2C_FUNCS:
		funcs = i2c_get_functionality(client->adapter);
		return (copy_to_user((unsigned long __user *)arg, &funcs,
		                     sizeof(unsigned long)))?-EFAULT:0;

	case I2C_RDWR:
		if (copy_from_user(&rdwr_arg, 
				   (struct i2c_rdwr_ioctl_data __user *)arg, 
				   sizeof(rdwr_arg)))
			return -EFAULT;

		/* Put an arbitrary limit on the number of messages that can
		 * be sent at once */
		if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
			return -EINVAL;
		
		rdwr_pa = (struct i2c_msg *)
			kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), 
			GFP_KERNEL);

		if (rdwr_pa == NULL) return -ENOMEM;

		if (copy_from_user(rdwr_pa, rdwr_arg.msgs,
				   rdwr_arg.nmsgs * sizeof(struct i2c_msg))) {
			kfree(rdwr_pa);
			return -EFAULT;
		}

		data_ptrs = kmalloc(rdwr_arg.nmsgs * sizeof(u8 __user *), GFP_KERNEL);
		if (data_ptrs == NULL) {
			kfree(rdwr_pa);
			return -ENOMEM;
		}

		res = 0;
		for( i=0; i<rdwr_arg.nmsgs; i++ ) {
			/* Limit the size of the message to a sane amount */
			if (rdwr_pa[i].len > 8192) {
				res = -EINVAL;
				break;
			}
			data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf;
			rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL);
			if(rdwr_pa[i].buf == NULL) {
				res = -ENOMEM;
				break;
			}
			if(copy_from_user(rdwr_pa[i].buf,
				data_ptrs[i],
				rdwr_pa[i].len)) {
					++i; /* Needs to be kfreed too */
					res = -EFAULT;
				break;
			}
		}
		if (res < 0) {
			int j;
			for (j = 0; j < i; ++j)
				kfree(rdwr_pa[j].buf);
			kfree(data_ptrs);
			kfree(rdwr_pa);
			return res;
		}

		res = i2c_transfer(client->adapter,
			rdwr_pa,
			rdwr_arg.nmsgs);
		while(i-- > 0) {
			if( res>=0 && (rdwr_pa[i].flags & I2C_M_RD)) {
				if(copy_to_user(
					data_ptrs[i],
					rdwr_pa[i].buf,
					rdwr_pa[i].len)) {
					res = -EFAULT;
				}
			}
			kfree(rdwr_pa[i].buf);
		}
		kfree(data_ptrs);
		kfree(rdwr_pa);
		return res;

	case I2C_SMBUS:
		if (copy_from_user(&data_arg,
		                   (struct i2c_smbus_ioctl_data __user *) arg,
		                   sizeof(struct i2c_smbus_ioctl_data)))
			return -EFAULT;
		if ((data_arg.size != I2C_SMBUS_BYTE) && 
		    (data_arg.size != I2C_SMBUS_QUICK) &&
		    (data_arg.size != I2C_SMBUS_BYTE_DATA) && 
		    (data_arg.size != I2C_SMBUS_WORD_DATA) &&
		    (data_arg.size != I2C_SMBUS_PROC_CALL) &&
		    (data_arg.size != I2C_SMBUS_BLOCK_DATA) &&
		    (data_arg.size != I2C_SMBUS_I2C_BLOCK_DATA) &&
		    (data_arg.size != I2C_SMBUS_BLOCK_PROC_CALL)) {
			dev_dbg(&client->adapter->dev,
				"size out of range (%x) in ioctl I2C_SMBUS.\n",
				data_arg.size);
			return -EINVAL;
		}
		/* Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1, 
		   so the check is valid if size==I2C_SMBUS_QUICK too. */
		if ((data_arg.read_write != I2C_SMBUS_READ) && 
		    (data_arg.read_write != I2C_SMBUS_WRITE)) {
			dev_dbg(&client->adapter->dev, 
				"read_write out of range (%x) in ioctl I2C_SMBUS.\n",
				data_arg.read_write);
			return -EINVAL;
		}

		/* Note that command values are always valid! */

		if ((data_arg.size == I2C_SMBUS_QUICK) ||
		    ((data_arg.size == I2C_SMBUS_BYTE) && 
		    (data_arg.read_write == I2C_SMBUS_WRITE)))
			/* These are special: we do not use data */
			return i2c_smbus_xfer(client->adapter, client->addr,
					      client->flags,
					      data_arg.read_write,
					      data_arg.command,
					      data_arg.size, NULL);

		if (data_arg.data == NULL) {
			dev_dbg(&client->adapter->dev,
				"data is NULL pointer in ioctl I2C_SMBUS.\n");
			return -EINVAL;
		}

		if ((data_arg.size == I2C_SMBUS_BYTE_DATA) ||
		    (data_arg.size == I2C_SMBUS_BYTE))
			datasize = sizeof(data_arg.data->byte);
		else if ((data_arg.size == I2C_SMBUS_WORD_DATA) || 
		         (data_arg.size == I2C_SMBUS_PROC_CALL))
			datasize = sizeof(data_arg.data->word);
		else /* size == smbus block, i2c block, or block proc. call */
			datasize = sizeof(data_arg.data->block);

		if ((data_arg.size == I2C_SMBUS_PROC_CALL) || 
		    (data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) || 
		    (data_arg.read_write == I2C_SMBUS_WRITE)) {
			if (copy_from_user(&temp, data_arg.data, datasize))
				return -EFAULT;
		}
		res = i2c_smbus_xfer(client->adapter,client->addr,client->flags,
		      data_arg.read_write,
		      data_arg.command,data_arg.size,&temp);
		if (! res && ((data_arg.size == I2C_SMBUS_PROC_CALL) || 
		              (data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) || 
			      (data_arg.read_write == I2C_SMBUS_READ))) {
			if (copy_to_user(data_arg.data, &temp, datasize))
				return -EFAULT;
		}
		return res;

	default:
		return i2c_control(client,cmd,arg);
	}
	return 0;
}

static int i2cdev_open(struct inode *inode, struct file *file)
{
	unsigned int minor = iminor(inode);
	struct i2c_client *client;
	struct i2c_adapter *adap;
	struct i2c_dev *i2c_dev;

	i2c_dev = i2c_dev_get_by_minor(minor);
	if (!i2c_dev)
		return -ENODEV;

	adap = i2c_get_adapter(i2c_dev->adap->nr);
	if (!adap)
		return -ENODEV;

	client = kmalloc(sizeof(*client), GFP_KERNEL);
	if (!client) {
		i2c_put_adapter(adap);
		return -ENOMEM;
	}
	memcpy(client, &i2cdev_client_template, sizeof(*client));

	/* registered with adapter, passed as client to user */
	client->adapter = adap;
	file->private_data = client;

	return 0;
}

static int i2cdev_release(struct inode *inode, struct file *file)
{
	struct i2c_client *client = file->private_data;

	i2c_put_adapter(client->adapter);
	kfree(client);
	file->private_data = NULL;

	return 0;
}

static struct file_operations i2cdev_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= i2cdev_read,
	.write		= i2cdev_write,
	.ioctl		= i2cdev_ioctl,
	.open		= i2cdev_open,
	.release	= i2cdev_release,
};

static struct class *i2c_dev_class;

static int i2cdev_attach_adapter(struct i2c_adapter *adap)
{
	struct i2c_dev *i2c_dev;
	struct device *dev;

	i2c_dev = get_free_i2c_dev(adap);
	if (IS_ERR(i2c_dev))
		return PTR_ERR(i2c_dev);

	pr_debug("i2c-dev: adapter [%s] registered as minor %d\n",
		 adap->name, i2c_dev->minor);

	/* register this i2c device with the driver core */
	i2c_dev->adap = adap;
	dev = &adap->dev;
	i2c_dev->class_dev = class_device_create(i2c_dev_class, NULL,
						 MKDEV(I2C_MAJOR, i2c_dev->minor),
						 dev, "i2c-%d", i2c_dev->minor);
	if (!i2c_dev->class_dev)
		goto error;
	class_device_create_file(i2c_dev->class_dev, &class_device_attr_name);
	return 0;
error:
	return_i2c_dev(i2c_dev);
	kfree(i2c_dev);
	return -ENODEV;
}

static int i2cdev_detach_adapter(struct i2c_adapter *adap)
{
	struct i2c_dev *i2c_dev;

	i2c_dev = i2c_dev_get_by_adapter(adap);
	if (!i2c_dev)
		return -ENODEV;

	return_i2c_dev(i2c_dev);
	class_device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, i2c_dev->minor));
	kfree(i2c_dev);

	pr_debug("i2c-dev: adapter [%s] unregistered\n", adap->name);
	return 0;
}

static int i2cdev_detach_client(struct i2c_client *client)
{
	return 0;
}

static struct i2c_driver i2cdev_driver = {
	.driver = {
		.name	= "dev_driver",
	},
	.id		= I2C_DRIVERID_I2CDEV,
	.attach_adapter	= i2cdev_attach_adapter,
	.detach_adapter	= i2cdev_detach_adapter,
	.detach_client	= i2cdev_detach_client,
};

static struct i2c_client i2cdev_client_template = {
	.name		= "I2C /dev entry",
	.addr		= -1,
	.driver		= &i2cdev_driver,
};

static int __init i2c_dev_init(void)
{
	int res;

	printk(KERN_INFO "i2c /dev entries driver\n");

	res = register_chrdev(I2C_MAJOR, "i2c", &i2cdev_fops);
	if (res)
		goto out;

	i2c_dev_class = class_create(THIS_MODULE, "i2c-dev");
	if (IS_ERR(i2c_dev_class))
		goto out_unreg_chrdev;

	res = i2c_add_driver(&i2cdev_driver);
	if (res)
		goto out_unreg_class;

	return 0;

out_unreg_class:
	class_destroy(i2c_dev_class);
out_unreg_chrdev:
	unregister_chrdev(I2C_MAJOR, "i2c");
out:
	printk(KERN_ERR "%s: Driver Initialisation failed\n", __FILE__);
	return res;
}

static void __exit i2c_dev_exit(void)
{
	i2c_del_driver(&i2cdev_driver);
	class_destroy(i2c_dev_class);
	unregister_chrdev(I2C_MAJOR,"i2c");
}

MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
		"Simon G. Vogl <simon@tk.uni-linz.ac.at>");
MODULE_DESCRIPTION("I2C /dev entries driver");
MODULE_LICENSE("GPL");

module_init(i2c_dev_init);
module_exit(i2c_dev_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	i2c-dev.c - i2c-bus driver, char device interface
	3
	4	Copyright (C) 1995-97 Simon G. Vogl
	5	Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
	6	Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
	7
	8	This program is free software; you can redistribute it and/or modify
	9	it under the terms of the GNU General Public License as published by
	10	the Free Software Foundation; either version 2 of the License, or
	11	(at your option) any later version.
	12
	13	This program is distributed in the hope that it will be useful,
	14	but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	GNU General Public License for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with this program; if not, write to the Free Software
	20	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	21	*/
	22
	23	/* Note that this is a complete rewrite of Simon Vogl's i2c-dev module.
	24	But I have used so much of his original code and ideas that it seems
	25	only fair to recognize him as co-author -- Frodo */
	26
	27	/* The I2C_RDWR ioctl code is written by Kolja Waschk <waschk@telos.de> */
	28
1da177e4 LT	29	#include <linux/kernel.h>
	30	#include <linux/module.h>
	31	#include <linux/fs.h>
	32	#include <linux/slab.h>
	33	#include <linux/smp_lock.h>
1da177e4 LT	34	#include <linux/init.h>
	35	#include <linux/i2c.h>
	36	#include <linux/i2c-dev.h>
d052d1be	37	#include <linux/platform_device.h>
1da177e4 LT	38	#include <asm/uaccess.h>
	39
	40	static struct i2c_client i2cdev_client_template;
	41
	42	struct i2c_dev {
	43	int minor;
	44	struct i2c_adapter *adap;
79472132	45	struct class_device *class_dev;
1da177e4 LT	46	};
	47	#define to_i2c_dev(d) container_of(d, struct i2c_dev, class_dev)
	48
	49	#define I2C_MINORS 256
	50	static struct i2c_dev *i2c_dev_array[I2C_MINORS];
	51	static DEFINE_SPINLOCK(i2c_dev_array_lock);
	52
	53	static struct i2c_dev *i2c_dev_get_by_minor(unsigned index)
	54	{
	55	struct i2c_dev *i2c_dev;
	56
	57	spin_lock(&i2c_dev_array_lock);
	58	i2c_dev = i2c_dev_array[index];
	59	spin_unlock(&i2c_dev_array_lock);
	60	return i2c_dev;
	61	}
	62
	63	static struct i2c_dev i2c_dev_get_by_adapter(struct i2c_adapter adap)
	64	{
	65	struct i2c_dev *i2c_dev = NULL;
	66
	67	spin_lock(&i2c_dev_array_lock);
	68	if ((i2c_dev_array[adap->nr]) &&
	69	(i2c_dev_array[adap->nr]->adap == adap))
	70	i2c_dev = i2c_dev_array[adap->nr];
	71	spin_unlock(&i2c_dev_array_lock);
	72	return i2c_dev;
	73	}
	74
	75	static struct i2c_dev get_free_i2c_dev(struct i2c_adapter adap)
	76	{
	77	struct i2c_dev *i2c_dev;
	78
5263ebb5	79	i2c_dev = kzalloc(sizeof(*i2c_dev), GFP_KERNEL);
1da177e4 LT	80	if (!i2c_dev)
1da177e4 LT	81	return ERR_PTR(-ENOMEM);
1da177e4 LT	82
	83	spin_lock(&i2c_dev_array_lock);
	84	if (i2c_dev_array[adap->nr]) {
	85	spin_unlock(&i2c_dev_array_lock);
	86	dev_err(&adap->dev, "i2c-dev already has a device assigned to this adapter\n");
	87	goto error;
	88	}
	89	i2c_dev->minor = adap->nr;
	90	i2c_dev_array[adap->nr] = i2c_dev;
	91	spin_unlock(&i2c_dev_array_lock);
	92	return i2c_dev;
	93	error:
	94	kfree(i2c_dev);
	95	return ERR_PTR(-ENODEV);
	96	}
	97
	98	static void return_i2c_dev(struct i2c_dev *i2c_dev)
	99	{
	100	spin_lock(&i2c_dev_array_lock);
	101	i2c_dev_array[i2c_dev->minor] = NULL;
	102	spin_unlock(&i2c_dev_array_lock);
	103	}
	104
	105	static ssize_t show_adapter_name(struct class_device class_dev, char buf)
	106	{
79472132 GKH	107	struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(class_dev->devt));
	108
	109	if (!i2c_dev)
	110	return -ENODEV;
1da177e4 LT	111	return sprintf(buf, "%s\n", i2c_dev->adap->name);
	112	}
	113	static CLASS_DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);
	114
	115	static ssize_t i2cdev_read (struct file file, char __user buf, size_t count,
	116	loff_t *offset)
	117	{
	118	char *tmp;
	119	int ret;
	120
	121	struct i2c_client client = (struct i2c_client )file->private_data;
	122
	123	if (count > 8192)
	124	count = 8192;
	125
	126	tmp = kmalloc(count,GFP_KERNEL);
	127	if (tmp==NULL)
	128	return -ENOMEM;
	129
	130	pr_debug("i2c-dev: i2c-%d reading %zd bytes.\n",
	131	iminor(file->f_dentry->d_inode), count);
	132
	133	ret = i2c_master_recv(client,tmp,count);
	134	if (ret >= 0)
	135	ret = copy_to_user(buf,tmp,count)?-EFAULT:ret;
	136	kfree(tmp);
	137	return ret;
	138	}
	139
	140	static ssize_t i2cdev_write (struct file file, const char __user buf, size_t count,
	141	loff_t *offset)
	142	{
	143	int ret;
	144	char *tmp;
	145	struct i2c_client client = (struct i2c_client )file->private_data;
	146
	147	if (count > 8192)
	148	count = 8192;
	149
	150	tmp = kmalloc(count,GFP_KERNEL);
	151	if (tmp==NULL)
	152	return -ENOMEM;
	153	if (copy_from_user(tmp,buf,count)) {
	154	kfree(tmp);
	155	return -EFAULT;
	156	}
	157
	158	pr_debug("i2c-dev: i2c-%d writing %zd bytes.\n",
	159	iminor(file->f_dentry->d_inode), count);
	160
	161	ret = i2c_master_send(client,tmp,count);
	162	kfree(tmp);
	163	return ret;
	164	}
	165
	166	static int i2cdev_ioctl(struct inode inode, struct file file,
	167	unsigned int cmd, unsigned long arg)
	168	{
	169	struct i2c_client client = (struct i2c_client )file->private_data;
	170	struct i2c_rdwr_ioctl_data rdwr_arg;
	171	struct i2c_smbus_ioctl_data data_arg;
	172	union i2c_smbus_data temp;
	173	struct i2c_msg *rdwr_pa;
	174	u8 __user **data_ptrs;
175	int i,datasize,res;
176	unsigned long funcs;
177
e8aafcb2 JD	178	dev_dbg(&client->adapter->dev, "ioctl, cmd=0x%02x, arg=0x%02lx\n",
e8aafcb2 JD	179	cmd, arg);
1da177e4 LT	180
	181	switch ( cmd ) {
	182	case I2C_SLAVE:
	183	case I2C_SLAVE_FORCE:
	184	if ((arg > 0x3ff) \|\|
	185	(((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
	186	return -EINVAL;
	187	if ((cmd == I2C_SLAVE) && i2c_check_addr(client->adapter,arg))
	188	return -EBUSY;
	189	client->addr = arg;
	190	return 0;
	191	case I2C_TENBIT:
	192	if (arg)
	193	client->flags \|= I2C_M_TEN;
	194	else
	195	client->flags &= ~I2C_M_TEN;
	196	return 0;
	197	case I2C_PEC:
	198	if (arg)
	199	client->flags \|= I2C_CLIENT_PEC;
	200	else
	201	client->flags &= ~I2C_CLIENT_PEC;
	202	return 0;
	203	case I2C_FUNCS:
	204	funcs = i2c_get_functionality(client->adapter);
	205	return (copy_to_user((unsigned long __user *)arg, &funcs,
	206	sizeof(unsigned long)))?-EFAULT:0;
	207
	208	case I2C_RDWR:
	209	if (copy_from_user(&rdwr_arg,
	210	(struct i2c_rdwr_ioctl_data __user *)arg,
	211	sizeof(rdwr_arg)))
	212	return -EFAULT;
	213
d68a861d	214	/* Put an arbitrary limit on the number of messages that can
1da177e4 LT	215	* be sent at once */
	216	if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
	217	return -EINVAL;
	218
	219	rdwr_pa = (struct i2c_msg *)
	220	kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg),
	221	GFP_KERNEL);
	222
	223	if (rdwr_pa == NULL) return -ENOMEM;
	224
	225	if (copy_from_user(rdwr_pa, rdwr_arg.msgs,
	226	rdwr_arg.nmsgs * sizeof(struct i2c_msg))) {
	227	kfree(rdwr_pa);
	228	return -EFAULT;
	229	}
	230
	231	data_ptrs = kmalloc(rdwr_arg.nmsgs * sizeof(u8 __user *), GFP_KERNEL);
	232	if (data_ptrs == NULL) {
	233	kfree(rdwr_pa);
	234	return -ENOMEM;
	235	}
	236
	237	res = 0;
	238	for( i=0; i<rdwr_arg.nmsgs; i++ ) {
	239	/* Limit the size of the message to a sane amount */
	240	if (rdwr_pa[i].len > 8192) {
	241	res = -EINVAL;
	242	break;
	243	}
	244	data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf;
	245	rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL);
	246	if(rdwr_pa[i].buf == NULL) {
	247	res = -ENOMEM;
	248	break;
	249	}
	250	if(copy_from_user(rdwr_pa[i].buf,
	251	data_ptrs[i],
	252	rdwr_pa[i].len)) {
	253	++i; /* Needs to be kfreed too */
	254	res = -EFAULT;
	255	break;
	256	}
	257	}
	258	if (res < 0) {
	259	int j;
	260	for (j = 0; j < i; ++j)
	261	kfree(rdwr_pa[j].buf);
	262	kfree(data_ptrs);
	263	kfree(rdwr_pa);
	264	return res;
	265	}
	266
	267	res = i2c_transfer(client->adapter,
	268	rdwr_pa,
	269	rdwr_arg.nmsgs);
	270	while(i-- > 0) {
	271	if( res>=0 && (rdwr_pa[i].flags & I2C_M_RD)) {
	272	if(copy_to_user(
	273	data_ptrs[i],
	274	rdwr_pa[i].buf,
	275	rdwr_pa[i].len)) {
	276	res = -EFAULT;
	277	}
	278	}
279	kfree(rdwr_pa[i].buf);
280	}
281	kfree(data_ptrs);
282	kfree(rdwr_pa);
283	return res;
284
285	case I2C_SMBUS:
286	if (copy_from_user(&data_arg,
287	(struct i2c_smbus_ioctl_data __user *) arg,
288	sizeof(struct i2c_smbus_ioctl_data)))
289	return -EFAULT;
290	if ((data_arg.size != I2C_SMBUS_BYTE) &&
291	(data_arg.size != I2C_SMBUS_QUICK) &&
292	(data_arg.size != I2C_SMBUS_BYTE_DATA) &&
293	(data_arg.size != I2C_SMBUS_WORD_DATA) &&
294	(data_arg.size != I2C_SMBUS_PROC_CALL) &&
295	(data_arg.size != I2C_SMBUS_BLOCK_DATA) &&
296	(data_arg.size != I2C_SMBUS_I2C_BLOCK_DATA) &&
297	(data_arg.size != I2C_SMBUS_BLOCK_PROC_CALL)) {
298	dev_dbg(&client->adapter->dev,
299	"size out of range (%x) in ioctl I2C_SMBUS.\n",
300	data_arg.size);
301	return -EINVAL;
302	}
303	/* Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1,
304	so the check is valid if size==I2C_SMBUS_QUICK too. */
305	if ((data_arg.read_write != I2C_SMBUS_READ) &&
306	(data_arg.read_write != I2C_SMBUS_WRITE)) {
307	dev_dbg(&client->adapter->dev,
308	"read_write out of range (%x) in ioctl I2C_SMBUS.\n",
309	data_arg.read_write);
310	return -EINVAL;
311	}
312
313	/* Note that command values are always valid! */
314
315	if ((data_arg.size == I2C_SMBUS_QUICK) \|\|
316	((data_arg.size == I2C_SMBUS_BYTE) &&
317	(data_arg.read_write == I2C_SMBUS_WRITE)))
318	/* These are special: we do not use data */
319	return i2c_smbus_xfer(client->adapter, client->addr,
320	client->flags,
321	data_arg.read_write,
322	data_arg.command,
323	data_arg.size, NULL);
324
325	if (data_arg.data == NULL) {
326	dev_dbg(&client->adapter->dev,
327	"data is NULL pointer in ioctl I2C_SMBUS.\n");
328	return -EINVAL;
329	}
330
331	if ((data_arg.size == I2C_SMBUS_BYTE_DATA) \|\|
332	(data_arg.size == I2C_SMBUS_BYTE))
333	datasize = sizeof(data_arg.data->byte);
334	else if ((data_arg.size == I2C_SMBUS_WORD_DATA) \|\|
335	(data_arg.size == I2C_SMBUS_PROC_CALL))
336	datasize = sizeof(data_arg.data->word);
337	else /* size == smbus block, i2c block, or block proc. call */
338	datasize = sizeof(data_arg.data->block);
339
340	if ((data_arg.size == I2C_SMBUS_PROC_CALL) \|\|
341	(data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) \|\|
342	(data_arg.read_write == I2C_SMBUS_WRITE)) {
343	if (copy_from_user(&temp, data_arg.data, datasize))
344	return -EFAULT;
345	}
346	res = i2c_smbus_xfer(client->adapter,client->addr,client->flags,
347	data_arg.read_write,
348	data_arg.command,data_arg.size,&temp);
349	if (! res && ((data_arg.size == I2C_SMBUS_PROC_CALL) \|\|
350	(data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) \|\|
351	(data_arg.read_write == I2C_SMBUS_READ))) {
352	if (copy_to_user(data_arg.data, &temp, datasize))
353	return -EFAULT;
354	}
355	return res;
356
357	default:
358	return i2c_control(client,cmd,arg);
359	}
360	return 0;
361	}
362
363	static int i2cdev_open(struct inode inode, struct file file)
364	{
365	unsigned int minor = iminor(inode);
366	struct i2c_client *client;
367	struct i2c_adapter *adap;
368	struct i2c_dev *i2c_dev;
369
370	i2c_dev = i2c_dev_get_by_minor(minor);
371	if (!i2c_dev)
372	return -ENODEV;
373
374	adap = i2c_get_adapter(i2c_dev->adap->nr);
375	if (!adap)
376	return -ENODEV;
377
378	client = kmalloc(sizeof(*client), GFP_KERNEL);
379	if (!client) {
380	i2c_put_adapter(adap);
381	return -ENOMEM;
382	}
383	memcpy(client, &i2cdev_client_template, sizeof(*client));
384
385	/* registered with adapter, passed as client to user */
386	client->adapter = adap;
387	file->private_data = client;
388
389	return 0;
390	}
391
392	static int i2cdev_release(struct inode inode, struct file file)
393	{
394	struct i2c_client *client = file->private_data;
395
396	i2c_put_adapter(client->adapter);
397	kfree(client);
398	file->private_data = NULL;
399
400	return 0;
401	}
402
403	static struct file_operations i2cdev_fops = {
404	.owner = THIS_MODULE,
405	.llseek = no_llseek,
406	.read = i2cdev_read,
407	.write = i2cdev_write,
408	.ioctl = i2cdev_ioctl,
409	.open = i2cdev_open,
410	.release = i2cdev_release,
411	};
412
79472132	413	static struct class *i2c_dev_class;
1da177e4 LT	414
	415	static int i2cdev_attach_adapter(struct i2c_adapter *adap)
	416	{
	417	struct i2c_dev *i2c_dev;
79472132	418	struct device *dev;
1da177e4 LT	419
	420	i2c_dev = get_free_i2c_dev(adap);
	421	if (IS_ERR(i2c_dev))
	422	return PTR_ERR(i2c_dev);
	423
b6d7b3d1 JD	424	pr_debug("i2c-dev: adapter [%s] registered as minor %d\n",
b6d7b3d1 JD	425	adap->name, i2c_dev->minor);
1da177e4 LT	426
	427	/* register this i2c device with the driver core */
	428	i2c_dev->adap = adap;
4941b395	429	dev = &adap->dev;
79472132 GKH	430	i2c_dev->class_dev = class_device_create(i2c_dev_class, NULL,
	431	MKDEV(I2C_MAJOR, i2c_dev->minor),
	432	dev, "i2c-%d", i2c_dev->minor);
	433	if (!i2c_dev->class_dev)
1da177e4	434	goto error;
79472132	435	class_device_create_file(i2c_dev->class_dev, &class_device_attr_name);
1da177e4 LT	436	return 0;
	437	error:
	438	return_i2c_dev(i2c_dev);
	439	kfree(i2c_dev);
79472132	440	return -ENODEV;
1da177e4 LT	441	}
	442
	443	static int i2cdev_detach_adapter(struct i2c_adapter *adap)
	444	{
	445	struct i2c_dev *i2c_dev;
	446
	447	i2c_dev = i2c_dev_get_by_adapter(adap);
	448	if (!i2c_dev)
	449	return -ENODEV;
	450
1da177e4	451	return_i2c_dev(i2c_dev);
79472132	452	class_device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, i2c_dev->minor));
1da177e4 LT	453	kfree(i2c_dev);
1da177e4 LT	454
b6d7b3d1	455	pr_debug("i2c-dev: adapter [%s] unregistered\n", adap->name);
1da177e4 LT	456	return 0;
	457	}
	458
	459	static int i2cdev_detach_client(struct i2c_client *client)
	460	{
	461	return 0;
	462	}
	463
1da177e4	464	static struct i2c_driver i2cdev_driver = {
35d8b2e6	465	.driver = {
35d8b2e6 LR	466	.name = "dev_driver",
35d8b2e6 LR	467	},
1da177e4	468	.id = I2C_DRIVERID_I2CDEV,
1da177e4 LT	469	.attach_adapter = i2cdev_attach_adapter,
	470	.detach_adapter = i2cdev_detach_adapter,
	471	.detach_client = i2cdev_detach_client,
1da177e4 LT	472	};
	473
	474	static struct i2c_client i2cdev_client_template = {
	475	.name = "I2C /dev entry",
	476	.addr = -1,
	477	.driver = &i2cdev_driver,
	478	};
	479
	480	static int __init i2c_dev_init(void)
	481	{
	482	int res;
	483
	484	printk(KERN_INFO "i2c /dev entries driver\n");
	485
	486	res = register_chrdev(I2C_MAJOR, "i2c", &i2cdev_fops);
	487	if (res)
	488	goto out;
	489
79472132 GKH	490	i2c_dev_class = class_create(THIS_MODULE, "i2c-dev");
79472132 GKH	491	if (IS_ERR(i2c_dev_class))
1da177e4 LT	492	goto out_unreg_chrdev;
	493
	494	res = i2c_add_driver(&i2cdev_driver);
	495	if (res)
	496	goto out_unreg_class;
	497
1da177e4 LT	498	return 0;
	499
	500	out_unreg_class:
79472132	501	class_destroy(i2c_dev_class);
1da177e4 LT	502	out_unreg_chrdev:
	503	unregister_chrdev(I2C_MAJOR, "i2c");
	504	out:
	505	printk(KERN_ERR "%s: Driver Initialisation failed\n", __FILE__);
	506	return res;
	507	}
	508
	509	static void __exit i2c_dev_exit(void)
	510	{
	511	i2c_del_driver(&i2cdev_driver);
79472132	512	class_destroy(i2c_dev_class);
1da177e4 LT	513	unregister_chrdev(I2C_MAJOR,"i2c");
	514	}
	515
	516	MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
	517	"Simon G. Vogl <simon@tk.uni-linz.ac.at>");
	518	MODULE_DESCRIPTION("I2C /dev entries driver");
	519	MODULE_LICENSE("GPL");
	520
	521	module_init(i2c_dev_init);
	522	module_exit(i2c_dev_exit);