alistair23-linux/drivers/hwmon/ds620.c
Thomas Gleixner 74ba9207e1 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 441 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:36:45 +02:00

258 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* ds620.c - Support for temperature sensor and thermostat DS620
*
* Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
*
* based on ds1621.c by Christian W. Zuckschwerdt <zany@triq.net>
*/
#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/platform_data/ds620.h>
/*
* Many DS620 constants specified below
* 15 14 13 12 11 10 09 08
* |Done|NVB |THF |TLF |R1 |R0 |AUTOC|1SHOT|
*
* 07 06 05 04 03 02 01 00
* |PO2 |PO1 |A2 |A1 |A0 | | | |
*/
#define DS620_REG_CONFIG_DONE 0x8000
#define DS620_REG_CONFIG_NVB 0x4000
#define DS620_REG_CONFIG_THF 0x2000
#define DS620_REG_CONFIG_TLF 0x1000
#define DS620_REG_CONFIG_R1 0x0800
#define DS620_REG_CONFIG_R0 0x0400
#define DS620_REG_CONFIG_AUTOC 0x0200
#define DS620_REG_CONFIG_1SHOT 0x0100
#define DS620_REG_CONFIG_PO2 0x0080
#define DS620_REG_CONFIG_PO1 0x0040
#define DS620_REG_CONFIG_A2 0x0020
#define DS620_REG_CONFIG_A1 0x0010
#define DS620_REG_CONFIG_A0 0x0008
/* The DS620 registers */
static const u8 DS620_REG_TEMP[3] = {
0xAA, /* input, word, RO */
0xA2, /* min, word, RW */
0xA0, /* max, word, RW */
};
#define DS620_REG_CONF 0xAC /* word, RW */
#define DS620_COM_START 0x51 /* no data */
#define DS620_COM_STOP 0x22 /* no data */
/* Each client has this additional data */
struct ds620_data {
struct i2c_client *client;
struct mutex update_lock;
char valid; /* !=0 if following fields are valid */
unsigned long last_updated; /* In jiffies */
s16 temp[3]; /* Register values, word */
};
static void ds620_init_client(struct i2c_client *client)
{
struct ds620_platform_data *ds620_info = dev_get_platdata(&client->dev);
u16 conf, new_conf;
new_conf = conf =
i2c_smbus_read_word_swapped(client, DS620_REG_CONF);
/* switch to continuous conversion mode */
new_conf &= ~DS620_REG_CONFIG_1SHOT;
/* already high at power-on, but don't trust the BIOS! */
new_conf |= DS620_REG_CONFIG_PO2;
/* thermostat mode according to platform data */
if (ds620_info && ds620_info->pomode == 1)
new_conf &= ~DS620_REG_CONFIG_PO1; /* PO_LOW */
else if (ds620_info && ds620_info->pomode == 2)
new_conf |= DS620_REG_CONFIG_PO1; /* PO_HIGH */
else
new_conf &= ~DS620_REG_CONFIG_PO2; /* always low */
/* with highest precision */
new_conf |= DS620_REG_CONFIG_R1 | DS620_REG_CONFIG_R0;
if (conf != new_conf)
i2c_smbus_write_word_swapped(client, DS620_REG_CONF, new_conf);
/* start conversion */
i2c_smbus_write_byte(client, DS620_COM_START);
}
static struct ds620_data *ds620_update_client(struct device *dev)
{
struct ds620_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
struct ds620_data *ret = data;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
int i;
int res;
dev_dbg(&client->dev, "Starting ds620 update\n");
for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
res = i2c_smbus_read_word_swapped(client,
DS620_REG_TEMP[i]);
if (res < 0) {
ret = ERR_PTR(res);
goto abort;
}
data->temp[i] = res;
}
data->last_updated = jiffies;
data->valid = 1;
}
abort:
mutex_unlock(&data->update_lock);
return ret;
}
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 ds620_data *data = ds620_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", ((data->temp[attr->index] / 8) * 625) / 10);
}
static ssize_t temp_store(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
int res;
long val;
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ds620_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
res = kstrtol(buf, 10, &val);
if (res)
return res;
val = (clamp_val(val, -128000, 128000) * 10 / 625) * 8;
mutex_lock(&data->update_lock);
data->temp[attr->index] = val;
i2c_smbus_write_word_swapped(client, DS620_REG_TEMP[attr->index],
data->temp[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t alarm_show(struct device *dev, struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ds620_data *data = ds620_update_client(dev);
struct i2c_client *client;
u16 conf, new_conf;
int res;
if (IS_ERR(data))
return PTR_ERR(data);
client = data->client;
/* reset alarms if necessary */
res = i2c_smbus_read_word_swapped(client, DS620_REG_CONF);
if (res < 0)
return res;
new_conf = conf = res;
new_conf &= ~attr->index;
if (conf != new_conf) {
res = i2c_smbus_write_word_swapped(client, DS620_REG_CONF,
new_conf);
if (res < 0)
return res;
}
return sprintf(buf, "%d\n", !!(conf & attr->index));
}
static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, 1);
static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 2);
static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, alarm, DS620_REG_CONFIG_TLF);
static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, DS620_REG_CONFIG_THF);
static struct attribute *ds620_attrs[] = {
&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,
NULL
};
ATTRIBUTE_GROUPS(ds620);
static int ds620_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct device *hwmon_dev;
struct ds620_data *data;
data = devm_kzalloc(dev, sizeof(struct ds620_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->client = client;
mutex_init(&data->update_lock);
/* Initialize the DS620 chip */
ds620_init_client(client);
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
data, ds620_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id ds620_id[] = {
{"ds620", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, ds620_id);
/* This is the driver that will be inserted */
static struct i2c_driver ds620_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "ds620",
},
.probe = ds620_probe,
.id_table = ds620_id,
};
module_i2c_driver(ds620_driver);
MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
MODULE_DESCRIPTION("DS620 driver");
MODULE_LICENSE("GPL");