User-space header file added for i2c-dev access

git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@159 7894878c-1315-0410-8ee3-d5d059ff63e0

kernel/include/i2c-dev.h

@@ -0,0 +1,150 @@
+/*
+    i2c-dev.h - Part of lm_sensors, Linux kernel modules for hardware
+            monitoring
+    Copyright (c) 1998  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.
+*/
+
+#ifndef SENSORS_I2C_DEV_H
+#define SENSORS_I2C_DEV_H
+
+#ifdef LM_SENSORS
+#include "i2c.h"
+#else /* ndef LM_SENSORS */
+#include <linux/i2c.h>
+#endif /* def LM_SENSORS */
+
+/* Some IOCTL commands are defined in <linux/i2c.h> */
+/* Note: 10-bit addresses are NOT supported! */
+
+#define I2C_SMBUS 0x0720
+
+/* This is the structure as used in the I2C_SMBUS ioctl call */
+struct i2c_smbus_data {
+  char read_write,
+  u8 command,
+  int size,
+  union smbus_data data
+};
+
+extern inline s32 i2c_smbus_access(int file, char read_write, u8 command, 
+                                   int size, union smbus_data *data)
+{
+  struct i2c_smbus_data args;
+  int res;
+
+  args.read_write = read_write;
+  args.command = command;
+  args.size = size;
+  if (data)
+    memcpy(&args.data,data,sizeof(union smbus_data));
+  res = ioctl(f,I2C_SMBUS,&args);
+  if (data)
+    memcpy(data,&args,sizeof(union smbus_data));
+  return res;
+}
+
+
+extern inline s32 i2c_smbus_write_quick(int file, u8 value)
+{
+  return i2c_smbus_access(file,value,0,SMBUS_QUICK,NULL);
+}
+
+extern inline s32 i2c_smbus_read_byte(int file)
+{
+  union smbus_data data;
+  if (i2c_smbus_access(file,SMBUS_READ,0,SMBUS_BYTE,&data))
+    return -1;
+  else
+    return 0x0FF & data.byte;
+}
+
+extern inline s32 i2c_smbus_write_byte(int file, u8 value)
+{
+  return i2c_smbus_access(file,SMBUS_WRITE,value, SMBUS_BYTE,NULL);
+}
+
+extern inline s32 i2c_smbus_read_byte_data(int file, u8 command)
+{
+  union smbus_data data;
+  if (i2c_smbus_access(file,SMBUS_READ,command,SMBUS_BYTE_DATA,&data))
+    return -1;
+  else
+    return 0x0FF & data.byte;
+}
+
+extern inline s32 i2c_smbus_write_byte_data(int file, u8 command, u8 value)
+{
+  union smbus_data data;
+  data.byte = value;
+  return i2c_smbus_access(file,SMBUS_WRITE,command,SMBUS_BYTE_DATA,&data);
+}
+
+extern inline s32 i2c_smbus_read_word_data(int file, u8 command)
+{
+  union smbus_data data;
+  if (i2c_smbus_access(file,SMBUS_READ,command,SMBUS_WORD_DATA,&data))
+    return -1;
+  else
+    return 0x0FFFF & data.word;
+}
+
+extern inline s32 i2c_smbus_write_word_data(int file, u8 command, u16 value)
+{
+  union smbus_data data;
+  data.word = value;
+  return i2c_smbus_access(file,SMBUS_WRITE,command,SMBUS_WORD_DATA, &data);
+}
+
+extern inline s32 i2c_smbus_process_call(int file, u8 command, u16 value)
+{
+  union smbus_data data;
+  data.word = value;
+  if (i2c_smbus_access(file,SMBUS_WRITE,command,SMBUS_PROC_CALL,&data))
+    return -1;
+  else
+    return 0x0FFFF & data.word;
+}
+
+
+/* Returns the number of read bytes */
+extern inline s32 i2c_smbus_read_block_data(int file, u8 command, u8 *values)
+{
+  union smbus_data data;
+  int i;
+  if (i2c_smbus_access(file,SMBUS_READ,command,SMBUS_BLOCK_DATA,&data))
+    return -1;
+  else {
+    for (i = 1; i <= data.block[0]; i++)
+      values[i-1] = data.block[i];
+    return data.block[0];
+  }
+}
+
+extern inline s32 i2c_smbus_write_block_data(int file, u8 command, u8 length,
+                                             u8 *values)
+{
+  union smbus_data data;
+  int i;
+  if (length > 32)
+    length = 32;
+  for (i = 1; i <= length; i++)
+    data.block[i] = values[i-1];
+  data.block[0] = length;
+  return i2c_smbus_access(file,SMBUS_WRITE,command,SMBUS_BLOCK_DATA,&data);
+}
+
+#endif