--- /dev/null
+/*
+ * 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);
projects / GitHub / exynos8895 / android_kernel_samsung_universal8895.git / commitdiff