diff options
Diffstat (limited to 'drivers/hwmon/jc42.c')
-rw-r--r-- | drivers/hwmon/jc42.c | 593 |
1 files changed, 593 insertions, 0 deletions
diff --git a/drivers/hwmon/jc42.c b/drivers/hwmon/jc42.c new file mode 100644 index 00000000000..340fc78c8dd --- /dev/null +++ b/drivers/hwmon/jc42.c @@ -0,0 +1,593 @@ +/* + * jc42.c - driver for Jedec JC42.4 compliant temperature sensors + * + * Copyright (c) 2010 Ericsson AB. + * + * Derived from lm77.c by Andras BALI <drewie@freemail.hu>. + * + * JC42.4 compliant temperature sensors are typically used on memory modules. + * + * 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> + +/* Addresses to scan */ +static const unsigned short normal_i2c[] = { + 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END }; + +/* JC42 registers. All registers are 16 bit. */ +#define JC42_REG_CAP 0x00 +#define JC42_REG_CONFIG 0x01 +#define JC42_REG_TEMP_UPPER 0x02 +#define JC42_REG_TEMP_LOWER 0x03 +#define JC42_REG_TEMP_CRITICAL 0x04 +#define JC42_REG_TEMP 0x05 +#define JC42_REG_MANID 0x06 +#define JC42_REG_DEVICEID 0x07 + +/* Status bits in temperature register */ +#define JC42_ALARM_CRIT_BIT 15 +#define JC42_ALARM_MAX_BIT 14 +#define JC42_ALARM_MIN_BIT 13 + +/* Configuration register defines */ +#define JC42_CFG_CRIT_ONLY (1 << 2) +#define JC42_CFG_SHUTDOWN (1 << 8) +#define JC42_CFG_HYST_SHIFT 9 +#define JC42_CFG_HYST_MASK 0x03 + +/* Capabilities */ +#define JC42_CAP_RANGE (1 << 2) + +/* Manufacturer IDs */ +#define ADT_MANID 0x11d4 /* Analog Devices */ +#define MAX_MANID 0x004d /* Maxim */ +#define IDT_MANID 0x00b3 /* IDT */ +#define MCP_MANID 0x0054 /* Microchip */ +#define NXP_MANID 0x1131 /* NXP Semiconductors */ +#define ONS_MANID 0x1b09 /* ON Semiconductor */ +#define STM_MANID 0x104a /* ST Microelectronics */ + +/* Supported chips */ + +/* Analog Devices */ +#define ADT7408_DEVID 0x0801 +#define ADT7408_DEVID_MASK 0xffff + +/* IDT */ +#define TS3000B3_DEVID 0x2903 /* Also matches TSE2002B3 */ +#define TS3000B3_DEVID_MASK 0xffff + +/* Maxim */ +#define MAX6604_DEVID 0x3e00 +#define MAX6604_DEVID_MASK 0xffff + +/* Microchip */ +#define MCP98242_DEVID 0x2000 +#define MCP98242_DEVID_MASK 0xfffc + +#define MCP98243_DEVID 0x2100 +#define MCP98243_DEVID_MASK 0xfffc + +#define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */ +#define MCP9843_DEVID_MASK 0xfffe + +/* NXP */ +#define SE97_DEVID 0xa200 +#define SE97_DEVID_MASK 0xfffc + +#define SE98_DEVID 0xa100 +#define SE98_DEVID_MASK 0xfffc + +/* ON Semiconductor */ +#define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */ +#define CAT6095_DEVID_MASK 0xffe0 + +/* ST Microelectronics */ +#define STTS424_DEVID 0x0101 +#define STTS424_DEVID_MASK 0xffff + +#define STTS424E_DEVID 0x0000 +#define STTS424E_DEVID_MASK 0xfffe + +static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 }; + +struct jc42_chips { + u16 manid; + u16 devid; + u16 devid_mask; +}; + +static struct jc42_chips jc42_chips[] = { + { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK }, + { IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK }, + { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK }, + { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK }, + { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK }, + { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK }, + { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK }, + { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK }, + { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK }, + { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK }, + { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK }, +}; + +/* Each client has this additional data */ +struct jc42_data { + struct device *hwmon_dev; + struct mutex update_lock; /* protect register access */ + bool extended; /* true if extended range supported */ + bool valid; + unsigned long last_updated; /* In jiffies */ + u16 orig_config; /* original configuration */ + u16 config; /* current configuration */ + u16 temp_input; /* Temperatures */ + u16 temp_crit; + u16 temp_min; + u16 temp_max; +}; + +static int jc42_probe(struct i2c_client *client, + const struct i2c_device_id *id); +static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info); +static int jc42_remove(struct i2c_client *client); +static int jc42_read_value(struct i2c_client *client, u8 reg); +static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value); + +static struct jc42_data *jc42_update_device(struct device *dev); + +static const struct i2c_device_id jc42_id[] = { + { "adt7408", 0 }, + { "cat94ts02", 0 }, + { "cat6095", 0 }, + { "jc42", 0 }, + { "max6604", 0 }, + { "mcp9805", 0 }, + { "mcp98242", 0 }, + { "mcp98243", 0 }, + { "mcp9843", 0 }, + { "se97", 0 }, + { "se97b", 0 }, + { "se98", 0 }, + { "stts424", 0 }, + { "tse2002b3", 0 }, + { "ts3000b3", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, jc42_id); + +#ifdef CONFIG_PM + +static int jc42_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct jc42_data *data = i2c_get_clientdata(client); + + data->config |= JC42_CFG_SHUTDOWN; + jc42_write_value(client, JC42_REG_CONFIG, data->config); + return 0; +} + +static int jc42_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct jc42_data *data = i2c_get_clientdata(client); + + data->config &= ~JC42_CFG_SHUTDOWN; + jc42_write_value(client, JC42_REG_CONFIG, data->config); + return 0; +} + +static const struct dev_pm_ops jc42_dev_pm_ops = { + .suspend = jc42_suspend, + .resume = jc42_resume, +}; + +#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops) +#else +#define JC42_DEV_PM_OPS NULL +#endif /* CONFIG_PM */ + +/* This is the driver that will be inserted */ +static struct i2c_driver jc42_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "jc42", + .pm = JC42_DEV_PM_OPS, + }, + .probe = jc42_probe, + .remove = jc42_remove, + .id_table = jc42_id, + .detect = jc42_detect, + .address_list = normal_i2c, +}; + +#define JC42_TEMP_MIN_EXTENDED (-40000) +#define JC42_TEMP_MIN 0 +#define JC42_TEMP_MAX 125000 + +static u16 jc42_temp_to_reg(int temp, bool extended) +{ + int ntemp = SENSORS_LIMIT(temp, + extended ? JC42_TEMP_MIN_EXTENDED : + JC42_TEMP_MIN, JC42_TEMP_MAX); + + /* convert from 0.001 to 0.0625 resolution */ + return (ntemp * 2 / 125) & 0x1fff; +} + +static int jc42_temp_from_reg(s16 reg) +{ + reg &= 0x1fff; + + /* sign extend register */ + if (reg & 0x1000) + reg |= 0xf000; + + /* convert from 0.0625 to 0.001 resolution */ + return reg * 125 / 2; +} + +/* sysfs stuff */ + +/* read routines for temperature limits */ +#define show(value) \ +static ssize_t show_##value(struct device *dev, \ + struct device_attribute *attr, \ + char *buf) \ +{ \ + struct jc42_data *data = jc42_update_device(dev); \ + if (IS_ERR(data)) \ + return PTR_ERR(data); \ + return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value)); \ +} + +show(temp_input); +show(temp_crit); +show(temp_min); +show(temp_max); + +/* read routines for hysteresis values */ +static ssize_t show_temp_crit_hyst(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct jc42_data *data = jc42_update_device(dev); + int temp, hyst; + + if (IS_ERR(data)) + return PTR_ERR(data); + + temp = jc42_temp_from_reg(data->temp_crit); + hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT) + & JC42_CFG_HYST_MASK]; + return sprintf(buf, "%d\n", temp - hyst); +} + +static ssize_t show_temp_max_hyst(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct jc42_data *data = jc42_update_device(dev); + int temp, hyst; + + if (IS_ERR(data)) + return PTR_ERR(data); + + temp = jc42_temp_from_reg(data->temp_max); + hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT) + & JC42_CFG_HYST_MASK]; + return sprintf(buf, "%d\n", temp - hyst); +} + +/* write routines */ +#define set(value, reg) \ +static ssize_t set_##value(struct device *dev, \ + struct device_attribute *attr, \ + const char *buf, size_t count) \ +{ \ + struct i2c_client *client = to_i2c_client(dev); \ + struct jc42_data *data = i2c_get_clientdata(client); \ + int err, ret = count; \ + long val; \ + if (strict_strtol(buf, 10, &val) < 0) \ + return -EINVAL; \ + mutex_lock(&data->update_lock); \ + data->value = jc42_temp_to_reg(val, data->extended); \ + err = jc42_write_value(client, reg, data->value); \ + if (err < 0) \ + ret = err; \ + mutex_unlock(&data->update_lock); \ + return ret; \ +} + +set(temp_min, JC42_REG_TEMP_LOWER); +set(temp_max, JC42_REG_TEMP_UPPER); +set(temp_crit, JC42_REG_TEMP_CRITICAL); + +/* JC42.4 compliant chips only support four hysteresis values. + * Pick best choice and go from there. */ +static ssize_t set_temp_crit_hyst(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct jc42_data *data = i2c_get_clientdata(client); + long val; + int diff, hyst; + int err; + int ret = count; + + if (strict_strtoul(buf, 10, &val) < 0) + return -EINVAL; + + diff = jc42_temp_from_reg(data->temp_crit) - val; + hyst = 0; + if (diff > 0) { + if (diff < 2250) + hyst = 1; /* 1.5 degrees C */ + else if (diff < 4500) + hyst = 2; /* 3.0 degrees C */ + else + hyst = 3; /* 6.0 degrees C */ + } + + mutex_lock(&data->update_lock); + data->config = (data->config + & ~(JC42_CFG_HYST_MASK << JC42_CFG_HYST_SHIFT)) + | (hyst << JC42_CFG_HYST_SHIFT); + err = jc42_write_value(client, JC42_REG_CONFIG, data->config); + if (err < 0) + ret = err; + mutex_unlock(&data->update_lock); + return ret; +} + +static ssize_t show_alarm(struct device *dev, + struct device_attribute *attr, char *buf) +{ + u16 bit = to_sensor_dev_attr(attr)->index; + struct jc42_data *data = jc42_update_device(dev); + u16 val; + + if (IS_ERR(data)) + return PTR_ERR(data); + + val = data->temp_input; + if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY)) + val = 0; + return sprintf(buf, "%u\n", (val >> bit) & 1); +} + +static DEVICE_ATTR(temp1_input, S_IRUGO, + show_temp_input, NULL); +static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, + show_temp_crit, set_temp_crit); +static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, + show_temp_min, set_temp_min); +static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, + show_temp_max, set_temp_max); + +static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, + show_temp_crit_hyst, set_temp_crit_hyst); +static DEVICE_ATTR(temp1_max_hyst, S_IRUGO, + show_temp_max_hyst, NULL); + +static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, + JC42_ALARM_CRIT_BIT); +static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, + JC42_ALARM_MIN_BIT); +static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, + JC42_ALARM_MAX_BIT); + +static struct attribute *jc42_attributes[] = { + &dev_attr_temp1_input.attr, + &dev_attr_temp1_crit.attr, + &dev_attr_temp1_min.attr, + &dev_attr_temp1_max.attr, + &dev_attr_temp1_crit_hyst.attr, + &dev_attr_temp1_max_hyst.attr, + &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, + &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, + &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, + NULL +}; + +static const struct attribute_group jc42_group = { + .attrs = jc42_attributes, +}; + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int jc42_detect(struct i2c_client *new_client, + struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = new_client->adapter; + int i, config, cap, manid, devid; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + + cap = jc42_read_value(new_client, JC42_REG_CAP); + config = jc42_read_value(new_client, JC42_REG_CONFIG); + manid = jc42_read_value(new_client, JC42_REG_MANID); + devid = jc42_read_value(new_client, JC42_REG_DEVICEID); + + if (cap < 0 || config < 0 || manid < 0 || devid < 0) + return -ENODEV; + + if ((cap & 0xff00) || (config & 0xf800)) + return -ENODEV; + + for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) { + struct jc42_chips *chip = &jc42_chips[i]; + if (manid == chip->manid && + (devid & chip->devid_mask) == chip->devid) { + strlcpy(info->type, "jc42", I2C_NAME_SIZE); + return 0; + } + } + return -ENODEV; +} + +static int jc42_probe(struct i2c_client *new_client, + const struct i2c_device_id *id) +{ + struct jc42_data *data; + int config, cap, err; + + data = kzalloc(sizeof(struct jc42_data), GFP_KERNEL); + if (!data) { + err = -ENOMEM; + goto exit; + } + + i2c_set_clientdata(new_client, data); + mutex_init(&data->update_lock); + + cap = jc42_read_value(new_client, JC42_REG_CAP); + if (cap < 0) { + err = -EINVAL; + goto exit_free; + } + data->extended = !!(cap & JC42_CAP_RANGE); + + config = jc42_read_value(new_client, JC42_REG_CONFIG); + if (config < 0) { + err = -EINVAL; + goto exit_free; + } + data->orig_config = config; + if (config & JC42_CFG_SHUTDOWN) { + config &= ~JC42_CFG_SHUTDOWN; + jc42_write_value(new_client, JC42_REG_CONFIG, config); + } + data->config = config; + + /* Register sysfs hooks */ + err = sysfs_create_group(&new_client->dev.kobj, &jc42_group); + if (err) + goto exit_free; + + data->hwmon_dev = hwmon_device_register(&new_client->dev); + if (IS_ERR(data->hwmon_dev)) { + err = PTR_ERR(data->hwmon_dev); + goto exit_remove; + } + + return 0; + +exit_remove: + sysfs_remove_group(&new_client->dev.kobj, &jc42_group); +exit_free: + kfree(data); +exit: + return err; +} + +static int jc42_remove(struct i2c_client *client) +{ + struct jc42_data *data = i2c_get_clientdata(client); + hwmon_device_unregister(data->hwmon_dev); + sysfs_remove_group(&client->dev.kobj, &jc42_group); + if (data->config != data->orig_config) + jc42_write_value(client, JC42_REG_CONFIG, data->orig_config); + kfree(data); + return 0; +} + +/* All registers are word-sized. */ +static int jc42_read_value(struct i2c_client *client, u8 reg) +{ + int ret = i2c_smbus_read_word_data(client, reg); + if (ret < 0) + return ret; + return swab16(ret); +} + +static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value) +{ + return i2c_smbus_write_word_data(client, reg, swab16(value)); +} + +static struct jc42_data *jc42_update_device(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct jc42_data *data = i2c_get_clientdata(client); + struct jc42_data *ret = data; + int val; + + mutex_lock(&data->update_lock); + + if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { + val = jc42_read_value(client, JC42_REG_TEMP); + if (val < 0) { + ret = ERR_PTR(val); + goto abort; + } + data->temp_input = val; + + val = jc42_read_value(client, JC42_REG_TEMP_CRITICAL); + if (val < 0) { + ret = ERR_PTR(val); + goto abort; + } + data->temp_crit = val; + + val = jc42_read_value(client, JC42_REG_TEMP_LOWER); + if (val < 0) { + ret = ERR_PTR(val); + goto abort; + } + data->temp_min = val; + + val = jc42_read_value(client, JC42_REG_TEMP_UPPER); + if (val < 0) { + ret = ERR_PTR(val); + goto abort; + } + data->temp_max = val; + + data->last_updated = jiffies; + data->valid = true; + } +abort: + mutex_unlock(&data->update_lock); + return ret; +} + +static int __init sensors_jc42_init(void) +{ + return i2c_add_driver(&jc42_driver); +} + +static void __exit sensors_jc42_exit(void) +{ + i2c_del_driver(&jc42_driver); +} + +MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>"); +MODULE_DESCRIPTION("JC42 driver"); +MODULE_LICENSE("GPL"); + +module_init(sensors_jc42_init); +module_exit(sensors_jc42_exit); |