cregit-Linux how code gets into the kernel

Release 4.7 drivers/hwmon/ds1621.c

Directory: drivers/hwmon
/*
 * ds1621.c - Part of lm_sensors, Linux kernel modules for hardware
 *            monitoring
 * Christian W. Zuckschwerdt  <zany@triq.net>  2000-11-23
 * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
 * Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
 * the help of Jean Delvare <jdelvare@suse.de>
 *
 * The DS1621 device is a digital temperature/thermometer with 9-bit
 * resolution, a thermal alarm output (Tout), and user-defined minimum
 * and maximum temperature thresholds (TH and TL).
 *
 * The DS1625, DS1631, DS1721, and DS1731 are pin compatible with the DS1621
 * and similar in operation, with slight variations as noted in the device
 * datasheets (please refer to www.maximintegrated.com for specific
 * device information).
 *
 * Since the DS1621 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.
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <linux/kernel.h>

/* Supported devices */






enum chips { ds1621, ds1625, ds1631, ds1721, ds1731 };

/* Insmod parameters */

static int polarity = -1;
module_param(polarity, int, 0);
MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low");

/*
 * The Configuration/Status register
 *
 * - DS1621:
 *   7    6    5    4    3    2    1    0
 * |Done|THF |TLF |NVB | X  | X  |POL |1SHOT|
 *
 * - DS1625:
 *   7    6    5    4    3    2    1    0
 * |Done|THF |TLF |NVB | 1  | 0  |POL |1SHOT|
 *
 * - DS1631, DS1731:
 *   7    6    5    4    3    2    1    0
 * |Done|THF |TLF |NVB | R1 | R0 |POL |1SHOT|
 *
 * - DS1721:
 *   7    6    5    4    3    2    1    0
 * |Done| X  | X  | U  | R1 | R0 |POL |1SHOT|
 *
 * Where:
 * - 'X' is Reserved
 * - 'U' is Undefined
 */

#define DS1621_REG_CONFIG_NVB		0x10

#define DS1621_REG_CONFIG_RESOL		0x0C

#define DS1621_REG_CONFIG_POLARITY	0x02

#define DS1621_REG_CONFIG_1SHOT		0x01

#define DS1621_REG_CONFIG_DONE		0x80


#define DS1621_REG_CONFIG_RESOL_SHIFT	2

/* ds1721 conversion rates: {C/LSB, time(ms), resolution bit setting} */

static const unsigned short ds1721_convrates[] = {
	94,	/*  9-bits (0.5,  93.75, RES[0..1] = 0 */
	188,	/* 10-bits (0.25, 187.5, RES[0..1] = 1 */
	375,	/* 11-bits (0.125,  375, RES[0..1] = 2 */
	750,	/* 12-bits (0.0625, 750, RES[0..1] = 3 */
};


#define DS1621_CONVERSION_MAX	750

#define DS1625_CONVERSION_MAX	500


#define DS1621_TEMP_MAX	125000

#define DS1621_TEMP_MIN	(-55000)

/* The DS1621 temperature registers */

static const u8 DS1621_REG_TEMP[3] = {
	0xAA,		/* input, word, RO */
	0xA2,		/* min, word, RW */
	0xA1,		/* max, word, RW */
};

#define DS1621_REG_CONF			0xAC 
/* byte, RW */

#define DS1621_COM_START		0xEE 
/* no data */

#define DS1721_COM_START		0x51 
/* no data */

#define DS1621_COM_STOP			0x22 
/* no data */

/* The DS1621 configuration register */

#define DS1621_ALARM_TEMP_HIGH		0x40

#define DS1621_ALARM_TEMP_LOW		0x20

/* Conversions */

#define ALARMS_FROM_REG(val) ((val) & \
                        (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW))

/* Each client has this additional data */

struct ds1621_data {
	
struct i2c_client *client;
	
struct mutex update_lock;
	
char valid;			/* !=0 if following fields are valid */
	
unsigned long last_updated;	/* In jiffies */
	
enum chips kind;		/* device type */

	
u16 temp[3];			/* Register values, word */
	
u8 conf;			/* Register encoding, combined */
	
u8 zbits;			/* Resolution encoded as number of
                                         * zero bits */
	
u16 update_interval;		/* Conversion rate in milliseconds */
};


static inline int DS1621_TEMP_FROM_REG(u16 reg) { return DIV_ROUND_CLOSEST(((s16)reg / 16) * 625, 10); }

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robert coulsonrobert coulson27100.00%1100.00%
Total27100.00%1100.00%

/* * TEMP: 0.001C/bit (-55C to +125C) * REG: * - 1621, 1625: 0.5C/bit, 7 zero-bits * - 1631, 1721, 1731: 0.0625C/bit, 4 zero-bits */
static inline u16 DS1621_TEMP_TO_REG(long temp, u8 zbits) { temp = clamp_val(temp, DS1621_TEMP_MIN, DS1621_TEMP_MAX); temp = DIV_ROUND_CLOSEST(temp * (1 << (8 - zbits)), 1000) << zbits; return temp; }

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robert coulsonrobert coulson2960.42%150.00%
guenter roeckguenter roeck1939.58%150.00%
Total48100.00%2100.00%


static void ds1621_init_client(struct ds1621_data *data, struct i2c_client *client) { u8 conf, new_conf, sreg, resol; new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); /* switch to continuous conversion mode */ new_conf &= ~DS1621_REG_CONFIG_1SHOT; /* setup output polarity */ if (polarity == 0) new_conf &= ~DS1621_REG_CONFIG_POLARITY; else if (polarity == 1) new_conf |= DS1621_REG_CONFIG_POLARITY; if (conf != new_conf) i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf); switch (data->kind) { case ds1625: data->update_interval = DS1625_CONVERSION_MAX; data->zbits = 7; sreg = DS1621_COM_START; break; case ds1631: case ds1721: case ds1731: resol = (new_conf & DS1621_REG_CONFIG_RESOL) >> DS1621_REG_CONFIG_RESOL_SHIFT; data->update_interval = ds1721_convrates[resol]; data->zbits = 7 - resol; sreg = DS1721_COM_START; break; default: data->update_interval = DS1621_CONVERSION_MAX; data->zbits = 7; sreg = DS1621_COM_START; break; } /* start conversion */ i2c_smbus_write_byte(client, sreg); }

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robert coulsonrobert coulson7341.71%333.33%
aurelien jarnoaurelien jarno5531.43%111.11%
guenter roeckguenter roeck2514.29%222.22%
jean delvarejean delvare2112.00%222.22%
steven colesteven cole10.57%111.11%
Total175100.00%9100.00%


static struct ds1621_data *ds1621_update_client(struct device *dev) { struct ds1621_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; u8 new_conf; mutex_lock(&data->update_lock); if (time_after(jiffies, data->last_updated + data->update_interval) || !data->valid) { int i; dev_dbg(&client->dev, "Starting ds1621 update\n"); data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); for (i = 0; i < ARRAY_SIZE(data->temp); i++) data->temp[i] = i2c_smbus_read_word_swapped(client, DS1621_REG_TEMP[i]); /* reset alarms if necessary */ new_conf = data->conf; if (data->temp[0] > data->temp[1]) /* input > min */ new_conf &= ~DS1621_ALARM_TEMP_LOW; if (data->temp[0] < data->temp[2]) /* input < max */ new_conf &= ~DS1621_ALARM_TEMP_HIGH; if (data->conf != new_conf) i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf); data->last_updated = jiffies; data->valid = 1; } mutex_unlock(&data->update_lock); return data; }

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jean delvarejean delvare19791.63%457.14%
aurelien jarnoaurelien jarno83.72%114.29%
guenter roeckguenter roeck73.26%114.29%
robert coulsonrobert coulson31.40%114.29%
Total215100.00%7100.00%


static ssize_t show_temp(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct ds1621_data *data = ds1621_update_client(dev); return sprintf(buf, "%d\n", DS1621_TEMP_FROM_REG(data->temp[attr->index])); }

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aurelien jarnoaurelien jarno3761.67%120.00%
jean delvarejean delvare1830.00%240.00%
yani ioannouyani ioannou46.67%120.00%
robert coulsonrobert coulson11.67%120.00%
Total60100.00%5100.00%


static ssize_t set_temp(struct device *dev, struct device_attribute *da, const char *buf, size_t count) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct ds1621_data *data = dev_get_drvdata(dev); long val; int err; err = kstrtol(buf, 10, &val); if (err) return err; mutex_lock(&data->update_lock); data->temp[attr->index] = DS1621_TEMP_TO_REG(val, data->zbits); i2c_smbus_write_word_swapped(data->client, DS1621_REG_TEMP[attr->index], data->temp[attr->index]); mutex_unlock(&data->update_lock); return count; }

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jean delvarejean delvare9775.19%337.50%
guenter roeckguenter roeck2922.48%337.50%
aurelien jarnoaurelien jarno21.55%112.50%
robert coulsonrobert coulson10.78%112.50%
Total129100.00%8100.00%


static ssize_t show_alarms(struct device *dev, struct device_attribute *da, char *buf) { struct ds1621_data *data = ds1621_update_client(dev); return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf)); }

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jean delvarejean delvare45100.00%1100.00%
Total45100.00%1100.00%


static ssize_t show_alarm(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct ds1621_data *data = ds1621_update_client(dev); return sprintf(buf, "%d\n", !!(data->conf & attr->index)); }

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jean delvarejean delvare60100.00%1100.00%
Total60100.00%1100.00%


static ssize_t show_convrate(struct device *dev, struct device_attribute *da, char *buf) { struct ds1621_data *data = dev_get_drvdata(dev); return scnprintf(buf, PAGE_SIZE, "%hu\n", data->update_interval); }

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robert coulsonrobert coulson4295.45%150.00%
guenter roeckguenter roeck24.55%150.00%
Total44100.00%2100.00%


static ssize_t set_convrate(struct device *dev, struct device_attribute *da, const char *buf, size_t count) { struct ds1621_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; unsigned long convrate; s32 err; int resol = 0; err = kstrtoul(buf, 10, &convrate); if (err) return err; /* Convert rate into resolution bits */ while (resol < (ARRAY_SIZE(ds1721_convrates) - 1) && convrate > ds1721_convrates[resol]) resol++; mutex_lock(&data->update_lock); data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); data->conf &= ~DS1621_REG_CONFIG_RESOL; data->conf |= (resol << DS1621_REG_CONFIG_RESOL_SHIFT); i2c_smbus_write_byte_data(client, DS1621_REG_CONF, data->conf); data->update_interval = ds1721_convrates[resol]; data->zbits = 7 - resol; mutex_unlock(&data->update_lock); return count; }

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robert coulsonrobert coulson16695.95%266.67%
guenter roeckguenter roeck74.05%133.33%
Total173100.00%3100.00%

static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_convrate, set_convrate); static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1); static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2); static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, DS1621_ALARM_TEMP_LOW); static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, DS1621_ALARM_TEMP_HIGH); static struct attribute *ds1621_attributes[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, &sensor_dev_attr_temp1_min.dev_attr.attr, &sensor_dev_attr_temp1_max.dev_attr.attr, &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, &dev_attr_alarms.attr, &dev_attr_update_interval.attr, NULL };
static umode_t ds1621_attribute_visible(struct kobject *kobj, struct attribute *attr, int index) { struct device *dev = container_of(kobj, struct device, kobj); struct ds1621_data *data = dev_get_drvdata(dev); if (attr == &dev_attr_update_interval.attr) if (data->kind == ds1621 || data->kind == ds1625) /* shhh, we're hiding update_interval */ return 0; return attr->mode; }

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robert coulsonrobert coulson7497.37%266.67%
guenter roeckguenter roeck22.63%133.33%
Total76100.00%3100.00%

static const struct attribute_group ds1621_group = { .attrs = ds1621_attributes, .is_visible = ds1621_attribute_visible }; __ATTRIBUTE_GROUPS(ds1621);
static int ds1621_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct ds1621_data *data; struct device *hwmon_dev; data = devm_kzalloc(&client->dev, sizeof(struct ds1621_data), GFP_KERNEL); if (!data) return -ENOMEM; mutex_init(&data->update_lock); data->kind = id->driver_data; data->client = client; /* Initialize the DS1621 chip */ ds1621_init_client(data, client); hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev, client->name, data, ds1621_groups); return PTR_ERR_OR_ZERO(hwmon_dev); }

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jean delvarejean delvare5450.00%327.27%
guenter roeckguenter roeck2825.93%327.27%
aurelien jarnoaurelien jarno1110.19%19.09%
robert coulsonrobert coulson87.41%19.09%
mark m. hoffmanmark m. hoffman54.63%19.09%
fengguang wufengguang wu10.93%19.09%
tony jonestony jones10.93%19.09%
Total108100.00%11100.00%

static const struct i2c_device_id ds1621_id[] = { { "ds1621", ds1621 }, { "ds1625", ds1625 }, { "ds1631", ds1631 }, { "ds1721", ds1721 }, { "ds1731", ds1731 }, { } }; MODULE_DEVICE_TABLE(i2c, ds1621_id); /* This is the driver that will be inserted */ static struct i2c_driver ds1621_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "ds1621", }, .probe = ds1621_probe, .id_table = ds1621_id, }; module_i2c_driver(ds1621_driver); MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>"); MODULE_DESCRIPTION("DS1621 driver"); MODULE_LICENSE("GPL");

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PersonTokensPropCommitsCommitProp
jean delvarejean delvare69441.21%1032.26%
robert coulsonrobert coulson54832.54%516.13%
aurelien jarnoaurelien jarno27716.45%26.45%
guenter roeckguenter roeck1327.84%516.13%
mark m. hoffmanmark m. hoffman140.83%13.23%
ingo molnaringo molnar40.24%13.23%
greg kroah-hartmangreg kroah-hartman40.24%13.23%
yani ioannouyani ioannou40.24%13.23%
alexey dobriyanalexey dobriyan30.18%13.23%
fengguang wufengguang wu10.06%13.23%
tony jonestony jones10.06%13.23%
steven colesteven cole10.06%13.23%
axel linaxel lin10.06%13.23%
Total1684100.00%31100.00%
Directory: drivers/hwmon
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