linux-imx

/*

 * lm92 - Hardware monitoring driver

 * Copyright (C) 2005-2008  Jean Delvare <jdelvare@suse.de>

 *

 * Based on the lm90 driver, with some ideas taken from the lm_sensors

 * lm92 driver as well.

 *

 * The LM92 is a sensor chip made by National Semiconductor. It reports

 * its own temperature with a 0.0625 deg resolution and a 0.33 deg

 * accuracy. Complete datasheet can be obtained from National's website

 * at:

 *   http://www.national.com/pf/LM/LM92.html

 *

 * This driver also supports the MAX6635 sensor chip made by Maxim.

 * This chip is compatible with the LM92, but has a lesser accuracy

 * (1.0 deg). Complete datasheet can be obtained from Maxim's website

 * at:

 *   http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074

 *

 * Since the LM92 was the first chipset supported by this driver, most

 * comments will refer to this chipset, but are actually general and

 * concern all supported chipsets, unless mentioned otherwise.

 *

 * Support could easily be added for the National Semiconductor LM76

 * and Maxim MAX6633 and MAX6634 chips, which are mostly compatible

 * with the LM92.

 *

 * 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.

 */

​

#include <linux/module.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/i2c.h>

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

#include <linux/err.h>

#include <linux/mutex.h>

#include <linux/jiffies.h>

​

/*

 * The LM92 and MAX6635 have 2 two-state pins for address selection,

 * resulting in 4 possible addresses.

 */

static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,

                        I2C_CLIENT_END };

enum chips { lm92, max6635 };

​

/* The LM92 registers */

#define LM92_REG_CONFIG         0x01 /* 8-bit, RW */

#define LM92_REG_TEMP           0x00 /* 16-bit, RO */

#define LM92_REG_TEMP_HYST      0x02 /* 16-bit, RW */

#define LM92_REG_TEMP_CRIT      0x03 /* 16-bit, RW */

#define LM92_REG_TEMP_LOW       0x04 /* 16-bit, RW */

#define LM92_REG_TEMP_HIGH      0x05 /* 16-bit, RW */