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.
drivers/i2c/i2c-dev.c | 228 +++++++++++++++++++++++++++++++++++---------------
1 files changed, 160 insertions(+), 68 deletions(-)
diff -Nru a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
--- a/drivers/i2c/i2c-dev.c Mon May 19 15:58:41 2003
+++ b/drivers/i2c/i2c-dev.c Mon May 19 15:58:41 2003
@@ -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 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);
-
-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);
-
-static int i2cdev_release (struct inode *inode, struct file *file);
-
-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);
+static struct i2c_client i2cdev_client_template;
-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 {
+ 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 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,
-};
+#define I2C_MINORS 256
+static struct i2c_dev *i2c_dev_array[I2C_MINORS];
+static spinlock_t i2c_dev_array_lock = SPIN_LOCK_UNLOCKED;
-static struct i2c_client i2cdev_client_template = {
- .dev = {
- .name = "I2C /dev entry",
- },
- .id = 1,
- .addr = -1,
- .driver = &i2cdev_driver,
-};
+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;
+}
+
+struct i2c_dev *i2c_dev_get_by_adapter(struct i2c_adapter *adap)
+{
+ struct i2c_dev *i2c_dev = NULL;
+ int i;
+
+ 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_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 @@
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 @@
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 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 @@
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 @@
unsigned int minor = minor(inode->i_rdev);
struct i2c_client *client;
struct i2c_adapter *adap;
+ struct i2c_dev *i2c_dev;
- adap = i2c_get_adapter(minor);
- if (NULL == adap)
+ 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);
@@ -370,29 +400,68 @@
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;
- 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);
+ i2c_dev = get_free_i2c_dev();
+ if (IS_ERR(i2c_dev))
+ return PTR_ERR(i2c_dev);
+
+ 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;
- i = i2c_adapter_id(adap);
+ i2c_dev = i2c_dev_get_by_adapter(adap);
+ if (!i2c_dev)
+ return -ENODEV;
+
+ 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 @@
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 @@
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 @@
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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