[GitHub/mt8127/android_kernel_alcatel_ttab.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/init.h>
#include <linux/list.h>
#include <linux/i2c.h>
#include <linux/i2c-dev.h>
#include <asm/uaccess.h>

static struct i2c_driver i2cdev_driver;

struct i2c_dev {
	struct list_head list;
	struct i2c_adapter *adap;
	struct device *dev;
};

#define I2C_MINORS	256
static LIST_HEAD(i2c_dev_list);
static DEFINE_SPINLOCK(i2c_dev_list_lock);

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

	spin_lock(&i2c_dev_list_lock);
	list_for_each_entry(i2c_dev, &i2c_dev_list, list) {
		if (i2c_dev->adap->nr == index)
			goto found;
	}
	i2c_dev = NULL;
found:
	spin_unlock(&i2c_dev_list_lock);
	return i2c_dev;
}

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

	if (adap->nr >= I2C_MINORS) {
		printk(KERN_ERR "i2c-dev: Out of device minors (%d)\n",
		       adap->nr);
		return ERR_PTR(-ENODEV);
	}

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

	spin_lock(&i2c_dev_list_lock);
	list_add_tail(&i2c_dev->list, &i2c_dev_list);
	spin_unlock(&i2c_dev_list_lock);
	return i2c_dev;
}

static void return_i2c_dev(struct i2c_dev *i2c_dev)
{
	spin_lock(&i2c_dev_list_lock);
	list_del(&i2c_dev->list);
	spin_unlock(&i2c_dev_list_lock);
	kfree(i2c_dev);
}

static ssize_t show_adapter_name(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(dev->devt));

	if (!i2c_dev)
		return -ENODEV;
	return sprintf(buf, "%s\n", i2c_dev->adap->name);
}
static 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_path.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_path.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 put_user(funcs, (unsigned long __user *)arg);

	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;
			 * and don't let length change either. */
			if ((rdwr_pa[i].len > 8192) ||
			    (rdwr_pa[i].flags & I2C_M_RECV_LEN)) {
				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_BROKEN) &&
		    (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.size == I2C_SMBUS_I2C_BLOCK_DATA) ||
		    (data_arg.read_write == I2C_SMBUS_WRITE)) {
			if (copy_from_user(&temp, data_arg.data, datasize))
				return -EFAULT;
		}
		if (data_arg.size == I2C_SMBUS_I2C_BLOCK_BROKEN) {
			/* Convert old I2C block commands to the new
			   convention. This preserves binary compatibility. */
			data_arg.size = I2C_SMBUS_I2C_BLOCK_DATA;
			if (data_arg.read_write == I2C_SMBUS_READ)
				temp.block[0] = I2C_SMBUS_BLOCK_MAX;
		}
		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 = kzalloc(sizeof(*client), GFP_KERNEL);
	if (!client) {
		i2c_put_adapter(adap);
		return -ENOMEM;
	}
	snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr);
	client->driver = &i2cdev_driver;

	/* 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 const 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;
	int res;

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

	/* register this i2c device with the driver core */
	i2c_dev->dev = device_create(i2c_dev_class, &adap->dev,
				     MKDEV(I2C_MAJOR, adap->nr),
				     "i2c-%d", adap->nr);
	if (IS_ERR(i2c_dev->dev)) {
		res = PTR_ERR(i2c_dev->dev);
		goto error;
	}
	res = device_create_file(i2c_dev->dev, &dev_attr_name);
	if (res)
		goto error_destroy;

	pr_debug("i2c-dev: adapter [%s] registered as minor %d\n",
		 adap->name, adap->nr);
	return 0;
error_destroy:
	device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
error:
	return_i2c_dev(i2c_dev);
	return res;
}

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

	i2c_dev = i2c_dev_get_by_minor(adap->nr);
	if (!i2c_dev) /* attach_adapter must have failed */
		return 0;

	device_remove_file(i2c_dev->dev, &dev_attr_name);
	return_i2c_dev(i2c_dev);
	device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));

	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 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	1	/*
438d6c2c	2	i2c-dev.c - i2c-bus driver, char device interface
1da177e4 LT	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>
1da177e4	33	#include <linux/init.h>
f3b3aadb	34	#include <linux/list.h>
1da177e4 LT	35	#include <linux/i2c.h>
	36	#include <linux/i2c-dev.h>
	37	#include <asm/uaccess.h>
	38
22f76e74	39	static struct i2c_driver i2cdev_driver;
1da177e4 LT	40
1da177e4 LT	41	struct i2c_dev {
f3b3aadb	42	struct list_head list;
1da177e4	43	struct i2c_adapter *adap;
ac11d060	44	struct device *dev;
1da177e4	45	};
1da177e4 LT	46
1da177e4 LT	47	#define I2C_MINORS 256
f3b3aadb JD	48	static LIST_HEAD(i2c_dev_list);
f3b3aadb JD	49	static DEFINE_SPINLOCK(i2c_dev_list_lock);
1da177e4 LT	50
	51	static struct i2c_dev *i2c_dev_get_by_minor(unsigned index)
	52	{
	53	struct i2c_dev *i2c_dev;
	54
f3b3aadb JD	55	spin_lock(&i2c_dev_list_lock);
	56	list_for_each_entry(i2c_dev, &i2c_dev_list, list) {
	57	if (i2c_dev->adap->nr == index)
	58	goto found;
	59	}
	60	i2c_dev = NULL;
	61	found:
	62	spin_unlock(&i2c_dev_list_lock);
1da177e4 LT	63	return i2c_dev;
	64	}
	65
1da177e4 LT	66	static struct i2c_dev get_free_i2c_dev(struct i2c_adapter adap)
	67	{
	68	struct i2c_dev *i2c_dev;
	69
f3b3aadb JD	70	if (adap->nr >= I2C_MINORS) {
	71	printk(KERN_ERR "i2c-dev: Out of device minors (%d)\n",
	72	adap->nr);
	73	return ERR_PTR(-ENODEV);
	74	}
	75
5263ebb5	76	i2c_dev = kzalloc(sizeof(*i2c_dev), GFP_KERNEL);
1da177e4 LT	77	if (!i2c_dev)
1da177e4 LT	78	return ERR_PTR(-ENOMEM);
9455e4c9	79	i2c_dev->adap = adap;
f3b3aadb JD	80
	81	spin_lock(&i2c_dev_list_lock);
	82	list_add_tail(&i2c_dev->list, &i2c_dev_list);
	83	spin_unlock(&i2c_dev_list_lock);
1da177e4	84	return i2c_dev;
1da177e4 LT	85	}
	86
	87	static void return_i2c_dev(struct i2c_dev *i2c_dev)
	88	{
f3b3aadb JD	89	spin_lock(&i2c_dev_list_lock);
	90	list_del(&i2c_dev->list);
	91	spin_unlock(&i2c_dev_list_lock);
07125ab2	92	kfree(i2c_dev);
1da177e4 LT	93	}
1da177e4 LT	94
ac11d060 GKH	95	static ssize_t show_adapter_name(struct device *dev,
ac11d060 GKH	96	struct device_attribute attr, char buf)
1da177e4	97	{
ac11d060	98	struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(dev->devt));
79472132 GKH	99
	100	if (!i2c_dev)
	101	return -ENODEV;
1da177e4 LT	102	return sprintf(buf, "%s\n", i2c_dev->adap->name);
1da177e4 LT	103	}
ac11d060	104	static DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);
1da177e4 LT	105
	106	static ssize_t i2cdev_read (struct file file, char __user buf, size_t count,
	107	loff_t *offset)
	108	{
	109	char *tmp;
	110	int ret;
	111
	112	struct i2c_client client = (struct i2c_client )file->private_data;
	113
	114	if (count > 8192)
	115	count = 8192;
	116
	117	tmp = kmalloc(count,GFP_KERNEL);
	118	if (tmp==NULL)
	119	return -ENOMEM;
	120
	121	pr_debug("i2c-dev: i2c-%d reading %zd bytes.\n",
cba0a128	122	iminor(file->f_path.dentry->d_inode), count);
1da177e4 LT	123
	124	ret = i2c_master_recv(client,tmp,count);
	125	if (ret >= 0)
	126	ret = copy_to_user(buf,tmp,count)?-EFAULT:ret;
	127	kfree(tmp);
	128	return ret;
	129	}
	130
	131	static ssize_t i2cdev_write (struct file file, const char __user buf, size_t count,
	132	loff_t *offset)
	133	{
	134	int ret;
	135	char *tmp;
	136	struct i2c_client client = (struct i2c_client )file->private_data;
	137
	138	if (count > 8192)
	139	count = 8192;
	140
	141	tmp = kmalloc(count,GFP_KERNEL);
	142	if (tmp==NULL)
	143	return -ENOMEM;
	144	if (copy_from_user(tmp,buf,count)) {
	145	kfree(tmp);
	146	return -EFAULT;
	147	}
	148
	149	pr_debug("i2c-dev: i2c-%d writing %zd bytes.\n",
cba0a128	150	iminor(file->f_path.dentry->d_inode), count);
1da177e4 LT	151
	152	ret = i2c_master_send(client,tmp,count);
	153	kfree(tmp);
	154	return ret;
	155	}
	156
	157	static int i2cdev_ioctl(struct inode inode, struct file file,
	158	unsigned int cmd, unsigned long arg)
	159	{
	160	struct i2c_client client = (struct i2c_client )file->private_data;
	161	struct i2c_rdwr_ioctl_data rdwr_arg;
	162	struct i2c_smbus_ioctl_data data_arg;
	163	union i2c_smbus_data temp;
	164	struct i2c_msg *rdwr_pa;
	165	u8 __user **data_ptrs;
	166	int i,datasize,res;
	167	unsigned long funcs;
	168
e8aafcb2 JD	169	dev_dbg(&client->adapter->dev, "ioctl, cmd=0x%02x, arg=0x%02lx\n",
e8aafcb2 JD	170	cmd, arg);
1da177e4 LT	171
	172	switch ( cmd ) {
	173	case I2C_SLAVE:
	174	case I2C_SLAVE_FORCE:
438d6c2c	175	if ((arg > 0x3ff) \|\|
1da177e4 LT	176	(((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
	177	return -EINVAL;
	178	if ((cmd == I2C_SLAVE) && i2c_check_addr(client->adapter,arg))
	179	return -EBUSY;
	180	client->addr = arg;
	181	return 0;
	182	case I2C_TENBIT:
	183	if (arg)
	184	client->flags \|= I2C_M_TEN;
	185	else
	186	client->flags &= ~I2C_M_TEN;
	187	return 0;
	188	case I2C_PEC:
	189	if (arg)
	190	client->flags \|= I2C_CLIENT_PEC;
	191	else
	192	client->flags &= ~I2C_CLIENT_PEC;
	193	return 0;
	194	case I2C_FUNCS:
	195	funcs = i2c_get_functionality(client->adapter);
2c003e8e	196	return put_user(funcs, (unsigned long __user *)arg);
1da177e4 LT	197
1da177e4 LT	198	case I2C_RDWR:
438d6c2c DB	199	if (copy_from_user(&rdwr_arg,
438d6c2c DB	200	(struct i2c_rdwr_ioctl_data __user *)arg,
1da177e4 LT	201	sizeof(rdwr_arg)))
	202	return -EFAULT;
	203
d68a861d	204	/* Put an arbitrary limit on the number of messages that can
1da177e4 LT	205	* be sent at once */
	206	if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
	207	return -EINVAL;
438d6c2c	208
1da177e4	209	rdwr_pa = (struct i2c_msg *)
438d6c2c	210	kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg),
1da177e4 LT	211	GFP_KERNEL);
	212
	213	if (rdwr_pa == NULL) return -ENOMEM;
	214
	215	if (copy_from_user(rdwr_pa, rdwr_arg.msgs,
	216	rdwr_arg.nmsgs * sizeof(struct i2c_msg))) {
	217	kfree(rdwr_pa);
	218	return -EFAULT;
	219	}
	220
	221	data_ptrs = kmalloc(rdwr_arg.nmsgs * sizeof(u8 __user *), GFP_KERNEL);
	222	if (data_ptrs == NULL) {
	223	kfree(rdwr_pa);
	224	return -ENOMEM;
	225	}
	226
	227	res = 0;
	228	for( i=0; i<rdwr_arg.nmsgs; i++ ) {
e265cfa1 DB	229	/* Limit the size of the message to a sane amount;
	230	* and don't let length change either. */
	231	if ((rdwr_pa[i].len > 8192) \|\|
	232	(rdwr_pa[i].flags & I2C_M_RECV_LEN)) {
1da177e4 LT	233	res = -EINVAL;
	234	break;
	235	}
	236	data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf;
	237	rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL);
	238	if(rdwr_pa[i].buf == NULL) {
	239	res = -ENOMEM;
	240	break;
	241	}
	242	if(copy_from_user(rdwr_pa[i].buf,
	243	data_ptrs[i],
	244	rdwr_pa[i].len)) {
	245	++i; /* Needs to be kfreed too */
	246	res = -EFAULT;
	247	break;
	248	}
	249	}
	250	if (res < 0) {
	251	int j;
	252	for (j = 0; j < i; ++j)
	253	kfree(rdwr_pa[j].buf);
	254	kfree(data_ptrs);
	255	kfree(rdwr_pa);
	256	return res;
	257	}
	258
	259	res = i2c_transfer(client->adapter,
	260	rdwr_pa,
	261	rdwr_arg.nmsgs);
	262	while(i-- > 0) {
	263	if( res>=0 && (rdwr_pa[i].flags & I2C_M_RD)) {
	264	if(copy_to_user(
	265	data_ptrs[i],
	266	rdwr_pa[i].buf,
	267	rdwr_pa[i].len)) {
	268	res = -EFAULT;
	269	}
	270	}
	271	kfree(rdwr_pa[i].buf);
	272	}
	273	kfree(data_ptrs);
	274	kfree(rdwr_pa);
	275	return res;
	276
	277	case I2C_SMBUS:
	278	if (copy_from_user(&data_arg,
	279	(struct i2c_smbus_ioctl_data __user *) arg,
	280	sizeof(struct i2c_smbus_ioctl_data)))
	281	return -EFAULT;
438d6c2c	282	if ((data_arg.size != I2C_SMBUS_BYTE) &&
1da177e4	283	(data_arg.size != I2C_SMBUS_QUICK) &&
438d6c2c	284	(data_arg.size != I2C_SMBUS_BYTE_DATA) &&
1da177e4 LT	285	(data_arg.size != I2C_SMBUS_WORD_DATA) &&
	286	(data_arg.size != I2C_SMBUS_PROC_CALL) &&
	287	(data_arg.size != I2C_SMBUS_BLOCK_DATA) &&
4b2643d7	288	(data_arg.size != I2C_SMBUS_I2C_BLOCK_BROKEN) &&
1da177e4 LT	289	(data_arg.size != I2C_SMBUS_I2C_BLOCK_DATA) &&
	290	(data_arg.size != I2C_SMBUS_BLOCK_PROC_CALL)) {
	291	dev_dbg(&client->adapter->dev,
	292	"size out of range (%x) in ioctl I2C_SMBUS.\n",
	293	data_arg.size);
	294	return -EINVAL;
	295	}
438d6c2c	296	/* Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1,
1da177e4	297	so the check is valid if size==I2C_SMBUS_QUICK too. */
438d6c2c	298	if ((data_arg.read_write != I2C_SMBUS_READ) &&
1da177e4	299	(data_arg.read_write != I2C_SMBUS_WRITE)) {
438d6c2c	300	dev_dbg(&client->adapter->dev,
1da177e4 LT	301	"read_write out of range (%x) in ioctl I2C_SMBUS.\n",
	302	data_arg.read_write);
	303	return -EINVAL;
	304	}
	305
	306	/* Note that command values are always valid! */
	307
	308	if ((data_arg.size == I2C_SMBUS_QUICK) \|\|
438d6c2c	309	((data_arg.size == I2C_SMBUS_BYTE) &&
1da177e4 LT	310	(data_arg.read_write == I2C_SMBUS_WRITE)))
	311	/* These are special: we do not use data */
	312	return i2c_smbus_xfer(client->adapter, client->addr,
	313	client->flags,
	314	data_arg.read_write,
	315	data_arg.command,
	316	data_arg.size, NULL);
	317
	318	if (data_arg.data == NULL) {
	319	dev_dbg(&client->adapter->dev,
	320	"data is NULL pointer in ioctl I2C_SMBUS.\n");
	321	return -EINVAL;
	322	}
	323
	324	if ((data_arg.size == I2C_SMBUS_BYTE_DATA) \|\|
	325	(data_arg.size == I2C_SMBUS_BYTE))
	326	datasize = sizeof(data_arg.data->byte);
438d6c2c	327	else if ((data_arg.size == I2C_SMBUS_WORD_DATA) \|\|
1da177e4 LT	328	(data_arg.size == I2C_SMBUS_PROC_CALL))
	329	datasize = sizeof(data_arg.data->word);
	330	else /* size == smbus block, i2c block, or block proc. call */
	331	datasize = sizeof(data_arg.data->block);
	332
438d6c2c DB	333	if ((data_arg.size == I2C_SMBUS_PROC_CALL) \|\|
438d6c2c DB	334	(data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) \|\|
4b2643d7	335	(data_arg.size == I2C_SMBUS_I2C_BLOCK_DATA) \|\|
1da177e4 LT	336	(data_arg.read_write == I2C_SMBUS_WRITE)) {
	337	if (copy_from_user(&temp, data_arg.data, datasize))
	338	return -EFAULT;
	339	}
4b2643d7 JD	340	if (data_arg.size == I2C_SMBUS_I2C_BLOCK_BROKEN) {
	341	/* Convert old I2C block commands to the new
	342	convention. This preserves binary compatibility. */
	343	data_arg.size = I2C_SMBUS_I2C_BLOCK_DATA;
	344	if (data_arg.read_write == I2C_SMBUS_READ)
	345	temp.block[0] = I2C_SMBUS_BLOCK_MAX;
	346	}
1da177e4 LT	347	res = i2c_smbus_xfer(client->adapter,client->addr,client->flags,
	348	data_arg.read_write,
	349	data_arg.command,data_arg.size,&temp);
438d6c2c DB	350	if (! res && ((data_arg.size == I2C_SMBUS_PROC_CALL) \|\|
438d6c2c DB	351	(data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) \|\|
1da177e4 LT	352	(data_arg.read_write == I2C_SMBUS_READ))) {
	353	if (copy_to_user(data_arg.data, &temp, datasize))
	354	return -EFAULT;
	355	}
	356	return res;
	357
	358	default:
	359	return i2c_control(client,cmd,arg);
	360	}
	361	return 0;
	362	}
	363
	364	static int i2cdev_open(struct inode inode, struct file file)
	365	{
	366	unsigned int minor = iminor(inode);
	367	struct i2c_client *client;
	368	struct i2c_adapter *adap;
	369	struct i2c_dev *i2c_dev;
	370
	371	i2c_dev = i2c_dev_get_by_minor(minor);
	372	if (!i2c_dev)
	373	return -ENODEV;
	374
	375	adap = i2c_get_adapter(i2c_dev->adap->nr);
	376	if (!adap)
	377	return -ENODEV;
	378
22f76e74	379	client = kzalloc(sizeof(*client), GFP_KERNEL);
1da177e4 LT	380	if (!client) {
	381	i2c_put_adapter(adap);
	382	return -ENOMEM;
	383	}
22f76e74 JD	384	snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr);
22f76e74 JD	385	client->driver = &i2cdev_driver;
1da177e4 LT	386
	387	/* registered with adapter, passed as client to user */
	388	client->adapter = adap;
	389	file->private_data = client;
	390
	391	return 0;
	392	}
	393
	394	static int i2cdev_release(struct inode inode, struct file file)
	395	{
	396	struct i2c_client *client = file->private_data;
	397
	398	i2c_put_adapter(client->adapter);
	399	kfree(client);
	400	file->private_data = NULL;
	401
	402	return 0;
	403	}
	404
2b8693c0	405	static const struct file_operations i2cdev_fops = {
1da177e4 LT	406	.owner = THIS_MODULE,
	407	.llseek = no_llseek,
	408	.read = i2cdev_read,
	409	.write = i2cdev_write,
	410	.ioctl = i2cdev_ioctl,
	411	.open = i2cdev_open,
	412	.release = i2cdev_release,
	413	};
	414
79472132	415	static struct class *i2c_dev_class;
1da177e4 LT	416
	417	static int i2cdev_attach_adapter(struct i2c_adapter *adap)
	418	{
	419	struct i2c_dev *i2c_dev;
defcb46e	420	int res;
1da177e4 LT	421
	422	i2c_dev = get_free_i2c_dev(adap);
	423	if (IS_ERR(i2c_dev))
	424	return PTR_ERR(i2c_dev);
	425
1da177e4	426	/* register this i2c device with the driver core */
ac11d060 GKH	427	i2c_dev->dev = device_create(i2c_dev_class, &adap->dev,
	428	MKDEV(I2C_MAJOR, adap->nr),
	429	"i2c-%d", adap->nr);
3bacb36d AM	430	if (IS_ERR(i2c_dev->dev)) {
3bacb36d AM	431	res = PTR_ERR(i2c_dev->dev);
1da177e4	432	goto error;
defcb46e	433	}
ac11d060	434	res = device_create_file(i2c_dev->dev, &dev_attr_name);
defcb46e JD	435	if (res)
defcb46e JD	436	goto error_destroy;
b32d20dc JD	437
	438	pr_debug("i2c-dev: adapter [%s] registered as minor %d\n",
	439	adap->name, adap->nr);
1da177e4	440	return 0;
defcb46e	441	error_destroy:
ac11d060	442	device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
1da177e4 LT	443	error:
1da177e4 LT	444	return_i2c_dev(i2c_dev);
defcb46e	445	return res;
1da177e4 LT	446	}
	447
	448	static int i2cdev_detach_adapter(struct i2c_adapter *adap)
	449	{
	450	struct i2c_dev *i2c_dev;
	451
9455e4c9	452	i2c_dev = i2c_dev_get_by_minor(adap->nr);
b32d20dc JD	453	if (!i2c_dev) /* attach_adapter must have failed */
b32d20dc JD	454	return 0;
1da177e4	455
ac11d060	456	device_remove_file(i2c_dev->dev, &dev_attr_name);
1da177e4	457	return_i2c_dev(i2c_dev);
ac11d060	458	device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
1da177e4	459
b6d7b3d1	460	pr_debug("i2c-dev: adapter [%s] unregistered\n", adap->name);
1da177e4 LT	461	return 0;
	462	}
	463
	464	static int i2cdev_detach_client(struct i2c_client *client)
	465	{
	466	return 0;
	467	}
	468
1da177e4	469	static struct i2c_driver i2cdev_driver = {
35d8b2e6	470	.driver = {
35d8b2e6 LR	471	.name = "dev_driver",
35d8b2e6 LR	472	},
1da177e4	473	.id = I2C_DRIVERID_I2CDEV,
1da177e4 LT	474	.attach_adapter = i2cdev_attach_adapter,
	475	.detach_adapter = i2cdev_detach_adapter,
	476	.detach_client = i2cdev_detach_client,
1da177e4 LT	477	};
1da177e4 LT	478
1da177e4 LT	479	static int __init i2c_dev_init(void)
	480	{
	481	int res;
	482
	483	printk(KERN_INFO "i2c /dev entries driver\n");
	484
	485	res = register_chrdev(I2C_MAJOR, "i2c", &i2cdev_fops);
	486	if (res)
	487	goto out;
	488
79472132 GKH	489	i2c_dev_class = class_create(THIS_MODULE, "i2c-dev");
79472132 GKH	490	if (IS_ERR(i2c_dev_class))
1da177e4 LT	491	goto out_unreg_chrdev;
	492
	493	res = i2c_add_driver(&i2cdev_driver);
	494	if (res)
	495	goto out_unreg_class;
	496
1da177e4 LT	497	return 0;
	498
	499	out_unreg_class:
79472132	500	class_destroy(i2c_dev_class);
1da177e4 LT	501	out_unreg_chrdev:
	502	unregister_chrdev(I2C_MAJOR, "i2c");
	503	out:
	504	printk(KERN_ERR "%s: Driver Initialisation failed\n", __FILE__);
	505	return res;
	506	}
	507
	508	static void __exit i2c_dev_exit(void)
	509	{
	510	i2c_del_driver(&i2cdev_driver);
79472132	511	class_destroy(i2c_dev_class);
1da177e4 LT	512	unregister_chrdev(I2C_MAJOR,"i2c");
	513	}
	514
	515	MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
	516	"Simon G. Vogl <simon@tk.uni-linz.ac.at>");
	517	MODULE_DESCRIPTION("I2C /dev entries driver");
	518	MODULE_LICENSE("GPL");
	519
	520	module_init(i2c_dev_init);
	521	module_exit(i2c_dev_exit);