linux-imx

/*

 * LM73 Sensor driver

 * Based on LM75

 *

 * Copyright (C) 2007, CenoSYS (www.cenosys.com).

 * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu).

 *

 * Guillaume Ligneul <guillaume.ligneul@gmail.com>

 * Adrien Demarez <adrien.demarez@bolloretelecom.eu>

 * Jeremy Laine <jeremy.laine@bolloretelecom.eu>

 * Chris Verges <kg4ysn@gmail.com>

 *

 * This software program is licensed subject to the GNU General Public License

 * (GPL).Version 2,June 1991, available at

 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html

 */

​

#include <linux/module.h>

#include <linux/init.h>

#include <linux/i2c.h>

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

#include <linux/err.h>

​

​

/* Addresses scanned */

static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c,

                    0x4d, 0x4e, I2C_CLIENT_END };

​

/* LM73 registers */

#define LM73_REG_INPUT      0x00

#define LM73_REG_CONF       0x01

#define LM73_REG_MAX        0x02

#define LM73_REG_MIN        0x03

#define LM73_REG_CTRL       0x04

#define LM73_REG_ID     0x07

​

#define LM73_ID         0x9001  /* 0x0190, byte-swapped */

#define DRVNAME         "lm73"

#define LM73_TEMP_MIN       (-256000 / 250)

#define LM73_TEMP_MAX       (255750 / 250)

​

#define LM73_CTRL_RES_SHIFT 5

#define LM73_CTRL_RES_MASK  (BIT(5) | BIT(6))

#define LM73_CTRL_TO_MASK   BIT(7)

​

#define LM73_CTRL_HI_SHIFT  2

#define LM73_CTRL_LO_SHIFT  1

​

static const unsigned short lm73_convrates[] = {

    14, /* 11-bits (0.25000 C/LSB): RES1 Bit = 0, RES0 Bit = 0 */

    28, /* 12-bits (0.12500 C/LSB): RES1 Bit = 0, RES0 Bit = 1 */

    56, /* 13-bits (0.06250 C/LSB): RES1 Bit = 1, RES0 Bit = 0 */

    112,    /* 14-bits (0.03125 C/LSB): RES1 Bit = 1, RES0 Bit = 1 */

};

​

struct lm73_data {

    struct i2c_client *client;

    struct mutex lock;

    u8 ctrl;            /* control register value */

};

​

/*-----------------------------------------------------------------------*/

​

static ssize_t temp_store(struct device *dev, struct device_attribute *da,

              const char *buf, size_t count)

{

    struct sensor_device_attribute *attr = to_sensor_dev_attr(da);

    struct lm73_data *data = dev_get_drvdata(dev);

    long temp;

    short value;

    s32 err;

​

    int status = kstrtol(buf, 10, &temp);

    if (status < 0)

        return status;

​

    /* Write value */

    value = clamp_val(temp / 250, LM73_TEMP_MIN, LM73_TEMP_MAX) << 5;

    err = i2c_smbus_write_word_swapped(data->client, attr->index, value);

    return (err < 0) ? err : count;

}

​

static ssize_t temp_show(struct device *dev, struct device_attribute *da,

             char *buf)

{

    struct sensor_device_attribute *attr = to_sensor_dev_attr(da);

    struct lm73_data *data = dev_get_drvdata(dev);

    int temp;

​

    s32 err = i2c_smbus_read_word_swapped(data->client, attr->index);

    if (err < 0)