patch-2.3.34 linux/drivers/i2c/i2c-dev.c
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- Lines: 553
- Date:
Thu Dec 16 13:59:38 1999
- Orig file:
v2.3.33/linux/drivers/i2c/i2c-dev.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.3.33/linux/drivers/i2c/i2c-dev.c linux/drivers/i2c/i2c-dev.c
@@ -0,0 +1,552 @@
+/*
+ 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>
+
+ 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 */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/malloc.h>
+#include <linux/version.h>
+
+/* If you want debugging uncomment: */
+/* #define DEBUG */
+
+#ifndef KERNEL_VERSION
+#define KERNEL_VERSION(a,b,c) (((a) << 16) | ((b) << 8) | (c))
+#endif
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,51)
+#include <linux/init.h>
+#else
+#define __init
+#endif
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,1,4))
+#define copy_from_user memcpy_fromfs
+#define copy_to_user memcpy_tofs
+#define get_user_data(to,from) ((to) = get_user(from),0)
+#else
+#include <asm/uaccess.h>
+#define get_user_data(to,from) get_user(to,from)
+#endif
+
+/* 2.0.0 kernel compatibility */
+#if LINUX_VERSION_CODE < 0x020100
+#define MODULE_AUTHOR(noone)
+#define MODULE_DESCRIPTION(none)
+#define MODULE_PARM(no,param)
+#define MODULE_PARM_DESC(no,description)
+#define EXPORT_SYMBOL(noexport)
+#define EXPORT_NO_SYMBOLS
+#endif
+
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+
+#ifdef MODULE
+extern int init_module(void);
+extern int cleanup_module(void);
+#endif /* def MODULE */
+
+/* struct file_operations changed too often in the 2.1 series for nice code */
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+static loff_t i2cdev_lseek (struct file *file, loff_t offset, int origin);
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,56))
+static long long i2cdev_lseek (struct file *file, long long offset, int origin);
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+static long long i2cdev_llseek (struct inode *inode, struct file *file,
+ long long offset, int origin);
+#else
+static int i2cdev_lseek (struct inode *inode, struct file *file, off_t offset,
+ int origin);
+#endif
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+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);
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+static long i2cdev_read (struct inode *inode, struct file *file, char *buf,
+ unsigned long count);
+static long i2cdev_write (struct inode *inode, struct file *file,
+ const char *buf, unsigned long offset);
+#else
+static int i2cdev_read(struct inode *inode, struct file *file, char *buf,
+ int count);
+static int i2cdev_write(struct inode *inode, struct file *file,
+ const char *buf, int count);
+#endif
+
+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);
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,31))
+static int i2cdev_release (struct inode *inode, struct file *file);
+#else
+static void i2cdev_release (struct inode *inode, struct file *file);
+#endif
+
+
+static int i2cdev_attach_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);
+
+#ifdef MODULE
+static
+#else
+extern
+#endif
+ int __init i2c_dev_init(void);
+static int i2cdev_cleanup(void);
+
+static struct file_operations i2cdev_fops = {
+ i2cdev_lseek,
+ i2cdev_read,
+ i2cdev_write,
+ NULL, /* i2cdev_readdir */
+ NULL, /* i2cdev_select */
+ i2cdev_ioctl,
+ NULL, /* i2cdev_mmap */
+ i2cdev_open,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,118)
+ NULL, /* i2cdev_flush */
+#endif
+ i2cdev_release,
+};
+
+#define I2CDEV_ADAPS_MAX I2C_ADAP_MAX
+static struct i2c_adapter *i2cdev_adaps[I2CDEV_ADAPS_MAX];
+
+static struct i2c_driver i2cdev_driver = {
+ /* name */ "i2c-dev dummy driver",
+ /* id */ I2C_DRIVERID_I2CDEV,
+ /* flags */ I2C_DF_DUMMY,
+ /* attach_adapter */ i2cdev_attach_adapter,
+ /* detach_client */ i2cdev_detach_client,
+ /* command */ i2cdev_command,
+ /* inc_use */ NULL,
+ /* dec_use */ NULL,
+};
+
+static struct i2c_client i2cdev_client_template = {
+ /* name */ "I2C /dev entry",
+ /* id */ 1,
+ /* flags */ 0,
+ /* addr */ -1,
+ /* adapter */ NULL,
+ /* driver */ &i2cdev_driver,
+ /* data */ NULL
+};
+
+static int i2cdev_initialized;
+
+/* Note that the lseek function is called llseek in 2.1 kernels. But things
+ are complicated enough as is. */
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+loff_t i2cdev_lseek (struct file *file, loff_t offset, int origin)
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,56))
+long long i2cdev_lseek (struct file *file, long long offset, int origin)
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+long long i2cdev_llseek (struct inode *inode, struct file *file,
+ long long offset, int origin)
+#else
+int i2cdev_lseek (struct inode *inode, struct file *file, off_t offset,
+ int origin)
+#endif
+{
+#ifdef DEBUG
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,56))
+ struct inode *inode = file->f_dentry->d_inode;
+#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70)) */
+ printk("i2c-dev,o: i2c-%d lseek to %ld bytes relative to %d.\n",
+ MINOR(inode->i_rdev),(long) offset,origin);
+#endif /* DEBUG */
+ return -ESPIPE;
+}
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+static ssize_t i2cdev_read (struct file *file, char *buf, size_t count,
+ loff_t *offset)
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+static long i2cdev_read (struct inode *inode, struct file *file, char *buf,
+ unsigned long count)
+#else
+static int i2cdev_read(struct inode *inode, struct file *file, char *buf,
+ int count)
+#endif
+{
+ char *tmp;
+ int ret;
+
+#ifdef DEBUG
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+ struct inode *inode = file->f_dentry->d_inode;
+#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70)) */
+#endif /* DEBUG */
+
+ struct i2c_client *client = (struct i2c_client *)file->private_data;
+
+ /* copy user space data to kernel space. */
+ tmp = kmalloc(count,GFP_KERNEL);
+ if (tmp==NULL)
+ return -ENOMEM;
+
+#ifdef DEBUG
+ printk("i2c-dev,o: i2c-%d reading %d bytes.\n",MINOR(inode->i_rdev),count);
+#endif
+
+ ret = i2c_master_recv(client,tmp,count);
+ copy_to_user(buf,tmp,count);
+ kfree(tmp);
+ return ret;
+}
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+static ssize_t i2cdev_write (struct file *file, const char *buf, size_t count,
+ loff_t *offset)
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+static long i2cdev_write (struct inode *inode, struct file *file,
+ const char *buf, unsigned long offset)
+#else
+static int i2cdev_write(struct inode *inode, struct file *file,
+ const char *buf, int count)
+#endif
+{
+ int ret;
+ char *tmp;
+ struct i2c_client *client = (struct i2c_client *)file->private_data;
+
+#ifdef DEBUG
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70))
+ struct inode *inode = file->f_dentry->d_inode;
+#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,70)) */
+#endif /* DEBUG */
+
+ /* copy user space data to kernel space. */
+ tmp = kmalloc(count,GFP_KERNEL);
+ if (tmp==NULL)
+ return -ENOMEM;
+ copy_from_user(tmp,buf,count);
+
+#ifdef DEBUG
+ printk("i2c-dev,o: i2c-%d writing %d bytes.\n",MINOR(inode->i_rdev),count);
+#endif
+ ret = i2c_master_send(client,tmp,count);
+ kfree(tmp);
+ return ret;
+}
+
+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_smbus_ioctl_data data_arg;
+ union i2c_smbus_data temp;
+ int ver,datasize,res;
+ unsigned long funcs;
+
+#ifdef DEBUG
+ printk("i2c-dev.o: i2c-%d ioctl, cmd: 0x%x, arg: %lx.\n",
+ MINOR(inode->i_rdev),cmd, arg);
+#endif /* DEBUG */
+
+ switch ( cmd ) {
+ case I2C_SLAVE:
+ if ((arg > 0x3ff) || (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
+ return -EINVAL;
+ 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_FUNCS:
+ if (! arg) {
+#ifdef DEBUG
+ printk("i2c-dev.o: NULL argument pointer in ioctl I2C_SMBUS.\n");
+#endif
+ return -EINVAL;
+ }
+ if (verify_area(VERIFY_WRITE,(unsigned long *) arg,
+ sizeof(unsigned long))) {
+#ifdef DEBUG
+ printk("i2c-dev.o: invalid argument pointer (%ld) "
+ "in IOCTL I2C_SMBUS.\n", arg);
+#endif
+ return -EINVAL;
+ }
+
+ funcs = i2c_get_functionality(client->adapter);
+ copy_to_user((unsigned long *)arg,&funcs,sizeof(unsigned long));
+ return 0;
+ case I2C_SMBUS:
+ if (! arg) {
+#ifdef DEBUG
+ printk("i2c-dev.o: NULL argument pointer in ioctl I2C_SMBUS.\n");
+#endif
+ return -EINVAL;
+ }
+ if (verify_area(VERIFY_READ,(struct i2c_smbus_ioctl_data *) arg,
+ sizeof(struct i2c_smbus_ioctl_data))) {
+#ifdef DEBUG
+ printk("i2c-dev.o: invalid argument pointer (%ld) "
+ "in IOCTL I2C_SMBUS.\n", arg);
+#endif
+ return -EINVAL;
+ }
+ copy_from_user(&data_arg,(struct i2c_smbus_ioctl_data *) arg,
+ sizeof(struct i2c_smbus_ioctl_data));
+ 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)) {
+#ifdef DEBUG
+ printk("i2c-dev.o: size out of range (%x) in ioctl I2C_SMBUS.\n",
+ data_arg.size);
+#endif
+ 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)) {
+#ifdef DEBUG
+ printk("i2c-dev.o: read_write out of range (%x) in ioctl I2C_SMBUS.\n",
+ data_arg.read_write);
+#endif
+ 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) {
+#ifdef DEBUG
+ printk("i2c-dev.o: data is NULL pointer in ioctl I2C_SMBUS.\n");
+#endif
+ return -EINVAL;
+ }
+
+ /* This seems unlogical but it is not: if the user wants to read a
+ value, we must write that value to user memory! */
+ ver = ((data_arg.read_write == I2C_SMBUS_WRITE) &&
+ (data_arg.size != I2C_SMBUS_PROC_CALL))?VERIFY_READ:VERIFY_WRITE;
+
+ 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 == I2C_SMBUS_BLOCK_DATA */
+ datasize = sizeof(data_arg.data->block);
+
+ if (verify_area(ver,data_arg.data,datasize)) {
+#ifdef DEBUG
+ printk("i2c-dev.o: invalid pointer data (%p) in ioctl I2C_SMBUS.\n",
+ data_arg.data);
+#endif
+ return -EINVAL;
+ }
+
+ if ((data_arg.size == I2C_SMBUS_PROC_CALL) ||
+ (data_arg.read_write == I2C_SMBUS_WRITE))
+ copy_from_user(&temp,data_arg.data,datasize);
+ 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.read_write == I2C_SMBUS_READ)))
+ copy_to_user(data_arg.data,&temp,datasize);
+ return res;
+
+ default:
+ return i2c_control(client,cmd,arg);
+ }
+ return 0;
+}
+
+int i2cdev_open (struct inode *inode, struct file *file)
+{
+ unsigned int minor = MINOR(inode->i_rdev);
+ struct i2c_client *client;
+
+ if ((minor >= I2CDEV_ADAPS_MAX) || ! (i2cdev_adaps[minor])) {
+#ifdef DEBUG
+ printk("i2c-dev.o: Trying to open unattached adapter i2c-%d\n",minor);
+#endif
+ return -ENODEV;
+ }
+
+ /* Note that we here allocate a client for later use, but we will *not*
+ register this client! Yes, this is safe. No, it is not very clean. */
+ if(! (client = kmalloc(sizeof(struct i2c_client),GFP_KERNEL)))
+ return -ENOMEM;
+ memcpy(client,&i2cdev_client_template,sizeof(struct i2c_client));
+ client->adapter = i2cdev_adaps[minor];
+ file->private_data = client;
+
+ i2cdev_adaps[minor]->inc_use(i2cdev_adaps[minor]);
+ MOD_INC_USE_COUNT;
+
+#ifdef DEBUG
+ printk("i2c-dev.o: opened i2c-%d\n",minor);
+#endif
+ return 0;
+}
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,31))
+static int i2cdev_release (struct inode *inode, struct file *file)
+#else
+static void i2cdev_release (struct inode *inode, struct file *file)
+#endif
+{
+ unsigned int minor = MINOR(inode->i_rdev);
+ kfree(file->private_data);
+ file->private_data=NULL;
+#ifdef DEBUG
+ printk("i2c-dev.o: Closed: i2c-%d\n", minor);
+#endif
+ MOD_DEC_USE_COUNT;
+ i2cdev_adaps[minor]->dec_use(i2cdev_adaps[minor]);
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,31))
+ return 0;
+#endif
+}
+
+int i2cdev_attach_adapter(struct i2c_adapter *adap)
+{
+ int i;
+
+ if ((i = i2c_adapter_id(adap)) < 0) {
+ printk("i2c-dev.o: Unknown adapter ?!?\n");
+ return -ENODEV;
+ }
+ if (i >= I2CDEV_ADAPS_MAX) {
+ printk("i2c-dev.o: Adapter number too large?!? (%d)\n",i);
+ return -ENODEV;
+ }
+
+ if (! i2cdev_adaps[i]) {
+ i2cdev_adaps[i] = adap;
+ printk("i2c-dev.o: Registered '%s' as minor %d\n",adap->name,i);
+ } else {
+ i2cdev_adaps[i] = NULL;
+#ifdef DEBUG
+ printk("i2c-dev.o: Adapter unregistered: %s\n",adap->name);
+#endif
+ }
+
+ return 0;
+}
+
+int i2cdev_detach_client(struct i2c_client *client)
+{
+ return 0;
+}
+
+static int i2cdev_command(struct i2c_client *client, unsigned int cmd,
+ void *arg)
+{
+ return -1;
+}
+
+int __init i2c_dev_init(void)
+{
+ int res;
+
+ printk("i2c-dev.o: i2c /dev entries driver module\n");
+
+ i2cdev_initialized = 0;
+ if (register_chrdev(I2C_MAJOR,"i2c",&i2cdev_fops)) {
+ printk("i2c-dev.o: unable to get major %d for i2c bus\n",I2C_MAJOR);
+ return -EIO;
+ }
+ i2cdev_initialized ++;
+
+ if ((res = i2c_add_driver(&i2cdev_driver))) {
+ printk("i2c-dev.o: Driver registration failed, module not inserted.\n");
+ i2cdev_cleanup();
+ return res;
+ }
+ i2cdev_initialized ++;
+ return 0;
+}
+
+int i2cdev_cleanup(void)
+{
+ int res;
+
+ if (i2cdev_initialized >= 2) {
+ if ((res = i2c_del_driver(&i2cdev_driver))) {
+ printk("i2c-dev.o: Driver deregistration failed, "
+ "module not removed.\n");
+ return res;
+ }
+ i2cdev_initialized ++;
+ }
+
+ if (i2cdev_initialized >= 1) {
+ if ((res = unregister_chrdev(I2C_MAJOR,"i2c"))) {
+ printk("i2c-dev.o: unable to release major %d for i2c bus\n",I2C_MAJOR);
+ return res;
+ }
+ i2cdev_initialized --;
+ }
+ return 0;
+}
+
+EXPORT_NO_SYMBOLS;
+
+#ifdef MODULE
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and Simon G. Vogl <simon@tk.uni-linz.ac.at>");
+MODULE_DESCRIPTION("I2C /dev entries driver");
+
+int init_module(void)
+{
+ return i2c_dev_init();
+}
+
+int cleanup_module(void)
+{
+ return i2cdev_cleanup();
+}
+
+#endif /* def MODULE */
+
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)