| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * w83l785ts.c - Part of lm_sensors, Linux kernel modules for hardware |
| * monitoring |
| * Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de> |
| * |
| * Inspired from the lm83 driver. The W83L785TS-S is a sensor chip made |
| * by Winbond. It reports a single external temperature with a 1 deg |
| * resolution and a 3 deg accuracy. Datasheet can be obtained from |
| * Winbond's website at: |
| * http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83L785TS-S.pdf |
| * |
| * Ported to Linux 2.6 by Wolfgang Ziegler <nuppla@gmx.at> and Jean Delvare |
| * <jdelvare@suse.de>. |
| * |
| * Thanks to James Bolt <james@evilpenguin.com> for benchmarking the read |
| * error handling mechanism. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/delay.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> |
| |
| /* How many retries on register read error */ |
| #define MAX_RETRIES 5 |
| |
| /* |
| * Address to scan |
| * Address is fully defined internally and cannot be changed. |
| */ |
| |
| static const unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END }; |
| |
| /* |
| * The W83L785TS-S registers |
| * Manufacturer ID is 0x5CA3 for Winbond. |
| */ |
| |
| #define W83L785TS_REG_MAN_ID1 0x4D |
| #define W83L785TS_REG_MAN_ID2 0x4C |
| #define W83L785TS_REG_CHIP_ID 0x4E |
| #define W83L785TS_REG_CONFIG 0x40 |
| #define W83L785TS_REG_TYPE 0x52 |
| #define W83L785TS_REG_TEMP 0x27 |
| #define W83L785TS_REG_TEMP_OVER 0x53 /* not sure about this one */ |
| |
| /* |
| * Conversions |
| * The W83L785TS-S uses signed 8-bit values. |
| */ |
| |
| #define TEMP_FROM_REG(val) ((val) * 1000) |
| |
| /* |
| * Functions declaration |
| */ |
| |
| static int w83l785ts_probe(struct i2c_client *client); |
| static int w83l785ts_detect(struct i2c_client *client, |
| struct i2c_board_info *info); |
| static void w83l785ts_remove(struct i2c_client *client); |
| static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval); |
| static struct w83l785ts_data *w83l785ts_update_device(struct device *dev); |
| |
| /* |
| * Driver data (common to all clients) |
| */ |
| |
| static const struct i2c_device_id w83l785ts_id[] = { |
| { "w83l785ts" }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, w83l785ts_id); |
| |
| static struct i2c_driver w83l785ts_driver = { |
| .class = I2C_CLASS_HWMON, |
| .driver = { |
| .name = "w83l785ts", |
| }, |
| .probe = w83l785ts_probe, |
| .remove = w83l785ts_remove, |
| .id_table = w83l785ts_id, |
| .detect = w83l785ts_detect, |
| .address_list = normal_i2c, |
| }; |
| |
| /* |
| * Client data (each client gets its own) |
| */ |
| |
| struct w83l785ts_data { |
| struct device *hwmon_dev; |
| struct mutex update_lock; |
| bool valid; /* false until following fields are valid */ |
| unsigned long last_updated; /* in jiffies */ |
| |
| /* registers values */ |
| s8 temp[2]; /* 0: input, 1: critical limit */ |
| }; |
| |
| /* |
| * Sysfs stuff |
| */ |
| |
| static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, |
| char *buf) |
| { |
| struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); |
| struct w83l785ts_data *data = w83l785ts_update_device(dev); |
| return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); |
| } |
| |
| static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); |
| static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1); |
| |
| /* |
| * Real code |
| */ |
| |
| /* Return 0 if detection is successful, -ENODEV otherwise */ |
| static int w83l785ts_detect(struct i2c_client *client, |
| struct i2c_board_info *info) |
| { |
| struct i2c_adapter *adapter = client->adapter; |
| u16 man_id; |
| u8 chip_id; |
| |
| if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
| return -ENODEV; |
| |
| /* detection */ |
| if ((w83l785ts_read_value(client, W83L785TS_REG_CONFIG, 0) & 0x80) |
| || (w83l785ts_read_value(client, W83L785TS_REG_TYPE, 0) & 0xFC)) { |
| dev_dbg(&adapter->dev, |
| "W83L785TS-S detection failed at 0x%02x\n", |
| client->addr); |
| return -ENODEV; |
| } |
| |
| /* Identification */ |
| man_id = (w83l785ts_read_value(client, W83L785TS_REG_MAN_ID1, 0) << 8) |
| + w83l785ts_read_value(client, W83L785TS_REG_MAN_ID2, 0); |
| chip_id = w83l785ts_read_value(client, W83L785TS_REG_CHIP_ID, 0); |
| |
| if (man_id != 0x5CA3 /* Winbond */ |
| || chip_id != 0x70) { /* W83L785TS-S */ |
| dev_dbg(&adapter->dev, |
| "Unsupported chip (man_id=0x%04X, chip_id=0x%02X)\n", |
| man_id, chip_id); |
| return -ENODEV; |
| } |
| |
| strscpy(info->type, "w83l785ts", I2C_NAME_SIZE); |
| |
| return 0; |
| } |
| |
| static int w83l785ts_probe(struct i2c_client *client) |
| { |
| struct w83l785ts_data *data; |
| struct device *dev = &client->dev; |
| int err; |
| |
| data = devm_kzalloc(dev, sizeof(struct w83l785ts_data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| i2c_set_clientdata(client, data); |
| mutex_init(&data->update_lock); |
| |
| /* |
| * Initialize the W83L785TS chip |
| * Nothing yet, assume it is already started. |
| */ |
| |
| err = device_create_file(dev, &sensor_dev_attr_temp1_input.dev_attr); |
| if (err) |
| return err; |
| |
| err = device_create_file(dev, &sensor_dev_attr_temp1_max.dev_attr); |
| if (err) |
| goto exit_remove; |
| |
| /* Register sysfs hooks */ |
| data->hwmon_dev = hwmon_device_register(dev); |
| if (IS_ERR(data->hwmon_dev)) { |
| err = PTR_ERR(data->hwmon_dev); |
| goto exit_remove; |
| } |
| |
| return 0; |
| |
| exit_remove: |
| device_remove_file(dev, &sensor_dev_attr_temp1_input.dev_attr); |
| device_remove_file(dev, &sensor_dev_attr_temp1_max.dev_attr); |
| return err; |
| } |
| |
| static void w83l785ts_remove(struct i2c_client *client) |
| { |
| struct w83l785ts_data *data = i2c_get_clientdata(client); |
| |
| hwmon_device_unregister(data->hwmon_dev); |
| device_remove_file(&client->dev, |
| &sensor_dev_attr_temp1_input.dev_attr); |
| device_remove_file(&client->dev, |
| &sensor_dev_attr_temp1_max.dev_attr); |
| } |
| |
| static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval) |
| { |
| int value, i; |
| struct device *dev; |
| const char *prefix; |
| |
| /* |
| * We might be called during detection, at which point the client |
| * isn't yet fully initialized, so we can't use dev_dbg on it |
| */ |
| if (i2c_get_clientdata(client)) { |
| dev = &client->dev; |
| prefix = ""; |
| } else { |
| dev = &client->adapter->dev; |
| prefix = "w83l785ts: "; |
| } |
| |
| /* |
| * Frequent read errors have been reported on Asus boards, so we |
| * retry on read errors. If it still fails (unlikely), return the |
| * default value requested by the caller. |
| */ |
| for (i = 1; i <= MAX_RETRIES; i++) { |
| value = i2c_smbus_read_byte_data(client, reg); |
| if (value >= 0) { |
| dev_dbg(dev, "%sRead 0x%02x from register 0x%02x.\n", |
| prefix, value, reg); |
| return value; |
| } |
| dev_dbg(dev, "%sRead failed, will retry in %d.\n", prefix, i); |
| msleep(i); |
| } |
| |
| dev_err(dev, "%sCouldn't read value from register 0x%02x.\n", prefix, |
| reg); |
| return defval; |
| } |
| |
| static struct w83l785ts_data *w83l785ts_update_device(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct w83l785ts_data *data = i2c_get_clientdata(client); |
| |
| mutex_lock(&data->update_lock); |
| |
| if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) { |
| dev_dbg(&client->dev, "Updating w83l785ts data.\n"); |
| data->temp[0] = w83l785ts_read_value(client, |
| W83L785TS_REG_TEMP, data->temp[0]); |
| data->temp[1] = w83l785ts_read_value(client, |
| W83L785TS_REG_TEMP_OVER, data->temp[1]); |
| |
| data->last_updated = jiffies; |
| data->valid = true; |
| } |
| |
| mutex_unlock(&data->update_lock); |
| |
| return data; |
| } |
| |
| module_i2c_driver(w83l785ts_driver); |
| |
| MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); |
| MODULE_DESCRIPTION("W83L785TS-S driver"); |
| MODULE_LICENSE("GPL"); |