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Commit 7a503879 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
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i2c: fix up i2c-dev driver based on previous core changes. 

This fixes the problem that adapter id's are not the minor number for the
i2c-dev devices anymore.  Also adds a i2c-dev class to let userspace know
which i2c-dev device is bound to which i2c adapter.
parent 75e90c70
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Showing with 158 additions and 66 deletions
drivers/i2c/i2c-dev.c
View file @ 7a503879
......@@ -3,6 +3,7 @@
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
......@@ -28,8 +29,6 @@
/* The devfs code is contributed by Philipp Matthias Hahn
<pmhahn@titan.lahn.de> */
/* $Id: i2c-dev.c,v 1.53 2003/01/21 08:08:16 kmalkki Exp $ */
/* If you want debugging uncomment: */
/* #define DEBUG 1 */
......@@ -44,54 +43,84 @@
#include <linux/i2c-dev.h>
#include <asm/uaccess.h>
/* struct file_operations changed too often in the 2.1 series for nice code */
static struct i2c_client i2cdev_client_template;
static ssize_t i2cdev_read (struct file *file, char *buf, size_t count,
loff_t *offset);
static ssize_t i2cdev_write (struct file *file, const char *buf, size_t count,
loff_t *offset);
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)
static int i2cdev_ioctl (struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg);
static int i2cdev_open (struct inode *inode, struct file *file);
#define I2C_MINORS 256
static struct i2c_dev *i2c_dev_array[I2C_MINORS];
static spinlock_t i2c_dev_array_lock = SPIN_LOCK_UNLOCKED;
static int i2cdev_release (struct inode *inode, struct file *file);
struct i2c_dev *i2c_dev_get_by_minor(unsigned index)
{
struct i2c_dev *i2c_dev;
static int i2cdev_attach_adapter(struct i2c_adapter *adap);
static int i2cdev_detach_adapter(struct i2c_adapter *adap);
static int i2cdev_detach_client(struct i2c_client *client);
static int i2cdev_command(struct i2c_client *client, unsigned int cmd,
void *arg);
spin_lock(&i2c_dev_array_lock);
i2c_dev = i2c_dev_array[index];
spin_unlock(&i2c_dev_array_lock);
return i2c_dev;
}
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,
};
struct i2c_dev *i2c_dev_get_by_adapter(struct i2c_adapter *adap)
{
struct i2c_dev *i2c_dev = NULL;
int i;
static struct i2c_driver i2cdev_driver = {
.owner = THIS_MODULE,
.name = "dev driver",
.id = I2C_DRIVERID_I2CDEV,
.flags = I2C_DF_NOTIFY,
.attach_adapter = i2cdev_attach_adapter,
.detach_adapter = i2cdev_detach_adapter,
.detach_client = i2cdev_detach_client,
.command = i2cdev_command,
};
spin_lock(&i2c_dev_array_lock);
for (i = 0; i < I2C_MINORS; ++i) {
if ((i2c_dev_array[i]) &&
(i2c_dev_array[i]->adap == adap)) {
i2c_dev = i2c_dev_array[i];
break;
}
}
spin_unlock(&i2c_dev_array_lock);
return i2c_dev;
}
static struct i2c_client i2cdev_client_template = {
.dev = {
.name = "I2C /dev entry",
},
.id = 1,
.addr = -1,
.driver = &i2cdev_driver,
};
static struct i2c_dev *get_free_i2c_dev(void)
{
struct i2c_dev *i2c_dev;
unsigned int i;
i2c_dev = kmalloc(sizeof(*i2c_dev), GFP_KERNEL);
if (!i2c_dev)
return ERR_PTR(-ENOMEM);
memset(i2c_dev, 0x00, sizeof(*i2c_dev));
spin_lock(&i2c_dev_array_lock);
for (i = 0; i < I2C_MINORS; ++i) {
if (i2c_dev_array[i])
continue;
i2c_dev->minor = i;
i2c_dev_array[i] = i2c_dev;
spin_unlock(&i2c_dev_array_lock);
return i2c_dev;
}
spin_unlock(&i2c_dev_array_lock);
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);
kfree(i2c_dev);
}
static ssize_t show_dev(struct class_device *class_dev, char *buf)
{
struct i2c_dev *i2c_dev = to_i2c_dev(class_dev);
return sprintf(buf, "%04x\n", MKDEV(I2C_MAJOR, i2c_dev->minor));
}
static CLASS_DEVICE_ATTR(dev, S_IRUGO, show_dev, NULL);
static ssize_t i2cdev_read (struct file *file, char *buf, size_t count,
loff_t *offset)
......@@ -104,7 +133,6 @@ static ssize_t i2cdev_read (struct file *file, char *buf, size_t count,
if (count > 8192)
count = 8192;
/* copy user space data to kernel space. */
tmp = kmalloc(count,GFP_KERNEL);
if (tmp==NULL)
return -ENOMEM;
......@@ -129,7 +157,6 @@ static ssize_t i2cdev_write (struct file *file, const char *buf, size_t count,
if (count > 8192)
count = 8192;
/* copy user space data to kernel space. */
tmp = kmalloc(count,GFP_KERNEL);
if (tmp==NULL)
return -ENOMEM;
......@@ -157,7 +184,7 @@ int i2cdev_ioctl (struct inode *inode, struct file *file, unsigned int cmd,
int i,datasize,res;
unsigned long funcs;
pr_debug("i2c-dev.o: i2c-%d ioctl, cmd: 0x%x, arg: %lx.\n",
dev_dbg(&client->dev, "i2c-%d ioctl, cmd: 0x%x, arg: %lx.\n",
minor(inode->i_rdev),cmd, arg);
switch ( cmd ) {
......@@ -242,13 +269,11 @@ int i2cdev_ioctl (struct inode *inode, struct file *file, unsigned int cmd,
rdwr_arg.nmsgs);
}
while(i-- > 0) {
if( res>=0 && (rdwr_pa[i].flags & I2C_M_RD))
{
if( res>=0 && (rdwr_pa[i].flags & I2C_M_RD)) {
if(copy_to_user(
rdwr_arg.msgs[i].buf,
rdwr_pa[i].buf,
rdwr_pa[i].len))
{
rdwr_pa[i].len)) {
res = -EFAULT;
}
}
......@@ -340,9 +365,14 @@ static int i2cdev_open(struct inode *inode, struct file *file)
unsigned int minor = minor(inode->i_rdev);
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(minor);
if (NULL == adap)
adap = i2c_get_adapter(i2c_dev->adap->nr);
if (!adap)
return -ENODEV;
client = kmalloc(sizeof(*client), GFP_KERNEL);
......@@ -370,29 +400,68 @@ static int i2cdev_release(struct inode *inode, struct file *file)
return 0;
}
int i2cdev_attach_adapter(struct i2c_adapter *adap)
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 = {
.name = "i2c-dev",
};
static int i2cdev_attach_adapter(struct i2c_adapter *adap)
{
int i;
struct i2c_dev *i2c_dev;
int retval;
i2c_dev = get_free_i2c_dev();
if (IS_ERR(i2c_dev))
return PTR_ERR(i2c_dev);
i = i2c_adapter_id(adap);
devfs_mk_cdev(MKDEV(I2C_MAJOR, i),
S_IFCHR|S_IRUSR|S_IWUSR, "i2c/%d", i);
dev_dbg(&adap->dev, "Registered as minor %d\n", i);
devfs_mk_cdev(MKDEV(I2C_MAJOR, i2c_dev->minor),
S_IFCHR|S_IRUSR|S_IWUSR, "i2c/%d", i2c_dev->minor);
dev_dbg(&adap->dev, "Registered as minor %d\n", i2c_dev->minor);
/* register this i2c device with the driver core */
i2c_dev->adap = adap;
if (adap->dev.parent == &legacy_bus)
i2c_dev->class_dev.dev = &adap->dev;
else
i2c_dev->class_dev.dev = adap->dev.parent;
i2c_dev->class_dev.class = &i2c_dev_class;
snprintf(i2c_dev->class_dev.class_id, BUS_ID_SIZE, "i2c-%d", i2c_dev->minor);
retval = class_device_register(&i2c_dev->class_dev);
if (retval)
goto error;
class_device_create_file(&i2c_dev->class_dev, &class_device_attr_dev);
return 0;
error:
return_i2c_dev(i2c_dev);
return retval;
}
int i2cdev_detach_adapter(struct i2c_adapter *adap)
static int i2cdev_detach_adapter(struct i2c_adapter *adap)
{
int i;
struct i2c_dev *i2c_dev;
i2c_dev = i2c_dev_get_by_adapter(adap);
if (!i2c_dev)
return -ENODEV;
i = i2c_adapter_id(adap);
class_device_unregister(&i2c_dev->class_dev);
devfs_remove("i2c/%d", i2c_dev->minor);
return_i2c_dev(i2c_dev);
devfs_remove("i2c/%d", i);
dev_dbg(&adap->dev, "Adapter unregistered\n");
return 0;
}
int i2cdev_detach_client(struct i2c_client *client)
static int i2cdev_detach_client(struct i2c_client *client)
{
return 0;
}
......@@ -403,7 +472,27 @@ static int i2cdev_command(struct i2c_client *client, unsigned int cmd,
return -1;
}
int __init i2c_dev_init(void)
static struct i2c_driver i2cdev_driver = {
.owner = THIS_MODULE,
.name = "dev driver",
.id = I2C_DRIVERID_I2CDEV,
.flags = I2C_DF_NOTIFY,
.attach_adapter = i2cdev_attach_adapter,
.detach_adapter = i2cdev_detach_adapter,
.detach_client = i2cdev_detach_client,
.command = i2cdev_command,
};
static struct i2c_client i2cdev_client_template = {
.dev = {
.name = "I2C /dev entry",
},
.id = 1,
.addr = -1,
.driver = &i2cdev_driver,
};
static int __init i2c_dev_init(void)
{
int res;
......@@ -416,6 +505,7 @@ int __init i2c_dev_init(void)
return -EIO;
}
devfs_mk_dir("i2c");
class_register(&i2c_dev_class);
if ((res = i2c_add_driver(&i2cdev_driver))) {
printk(KERN_ERR "i2c-dev.o: Driver registration failed, module not inserted.\n");
devfs_remove("i2c");
......@@ -428,11 +518,13 @@ int __init i2c_dev_init(void)
static void __exit i2c_dev_exit(void)
{
i2c_del_driver(&i2cdev_driver);
class_unregister(&i2c_dev_class);
devfs_remove("i2c");
unregister_chrdev(I2C_MAJOR,"i2c");
}
MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and Simon G. Vogl <simon@tk.uni-linz.ac.at>");
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");
......
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