| /* |
| * w83l785ts.c - Part of lm_sensors, Linux kernel modules for hardware |
| * monitoring |
| * Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org> |
| * |
| * 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 |
| * <khali@linux-fr.org>. |
| * |
| * Thanks to James Bolt <james@evilpenguin.com> for benchmarking the read |
| * error handling mechanism. |
| * |
| * 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/delay.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/jiffies.h> |
| #include <linux/i2c.h> |
| #include <linux/i2c-sensor.h> |
| #include <linux/hwmon.h> |
| #include <linux/err.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 unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END }; |
| |
| /* |
| * Insmod parameters |
| */ |
| |
| SENSORS_INSMOD_1(w83l785ts); |
| |
| /* |
| * 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 & 0x80 ? val-0x100 : val) * 1000) |
| |
| /* |
| * Functions declaration |
| */ |
| |
| static int w83l785ts_attach_adapter(struct i2c_adapter *adapter); |
| static int w83l785ts_detect(struct i2c_adapter *adapter, int address, |
| int kind); |
| static int w83l785ts_detach_client(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 struct i2c_driver w83l785ts_driver = { |
| .owner = THIS_MODULE, |
| .name = "w83l785ts", |
| .id = I2C_DRIVERID_W83L785TS, |
| .flags = I2C_DF_NOTIFY, |
| .attach_adapter = w83l785ts_attach_adapter, |
| .detach_client = w83l785ts_detach_client, |
| }; |
| |
| /* |
| * Client data (each client gets its own) |
| */ |
| |
| struct w83l785ts_data { |
| struct i2c_client client; |
| struct class_device *class_dev; |
| struct semaphore update_lock; |
| char valid; /* zero until following fields are valid */ |
| unsigned long last_updated; /* in jiffies */ |
| |
| /* registers values */ |
| u8 temp, temp_over; |
| }; |
| |
| /* |
| * Sysfs stuff |
| */ |
| |
| static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct w83l785ts_data *data = w83l785ts_update_device(dev); |
| return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp)); |
| } |
| |
| static ssize_t show_temp_over(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct w83l785ts_data *data = w83l785ts_update_device(dev); |
| return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_over)); |
| } |
| |
| static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL); |
| static DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_over, NULL); |
| |
| /* |
| * Real code |
| */ |
| |
| static int w83l785ts_attach_adapter(struct i2c_adapter *adapter) |
| { |
| if (!(adapter->class & I2C_CLASS_HWMON)) |
| return 0; |
| return i2c_detect(adapter, &addr_data, w83l785ts_detect); |
| } |
| |
| /* |
| * The following function does more than just detection. If detection |
| * succeeds, it also registers the new chip. |
| */ |
| static int w83l785ts_detect(struct i2c_adapter *adapter, int address, int kind) |
| { |
| struct i2c_client *new_client; |
| struct w83l785ts_data *data; |
| int err = 0; |
| |
| |
| if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
| goto exit; |
| |
| if (!(data = kmalloc(sizeof(struct w83l785ts_data), GFP_KERNEL))) { |
| err = -ENOMEM; |
| goto exit; |
| } |
| memset(data, 0, sizeof(struct w83l785ts_data)); |
| |
| |
| /* The common I2C client data is placed right before the |
| * W83L785TS-specific data. */ |
| new_client = &data->client; |
| i2c_set_clientdata(new_client, data); |
| new_client->addr = address; |
| new_client->adapter = adapter; |
| new_client->driver = &w83l785ts_driver; |
| new_client->flags = 0; |
| |
| /* |
| * Now we do the remaining detection. A negative kind means that |
| * the driver was loaded with no force parameter (default), so we |
| * must both detect and identify the chip (actually there is only |
| * one possible kind of chip for now, W83L785TS-S). A zero kind means |
| * that the driver was loaded with the force parameter, the detection |
| * step shall be skipped. A positive kind means that the driver |
| * was loaded with the force parameter and a given kind of chip is |
| * requested, so both the detection and the identification steps |
| * are skipped. |
| */ |
| if (kind < 0) { /* detection */ |
| if (((w83l785ts_read_value(new_client, |
| W83L785TS_REG_CONFIG, 0) & 0x80) != 0x00) |
| || ((w83l785ts_read_value(new_client, |
| W83L785TS_REG_TYPE, 0) & 0xFC) != 0x00)) { |
| dev_dbg(&adapter->dev, |
| "W83L785TS-S detection failed at 0x%02x.\n", |
| address); |
| goto exit_free; |
| } |
| } |
| |
| if (kind <= 0) { /* identification */ |
| u16 man_id; |
| u8 chip_id; |
| |
| man_id = (w83l785ts_read_value(new_client, |
| W83L785TS_REG_MAN_ID1, 0) << 8) + |
| w83l785ts_read_value(new_client, |
| W83L785TS_REG_MAN_ID2, 0); |
| chip_id = w83l785ts_read_value(new_client, |
| W83L785TS_REG_CHIP_ID, 0); |
| |
| if (man_id == 0x5CA3) { /* Winbond */ |
| if (chip_id == 0x70) { /* W83L785TS-S */ |
| kind = w83l785ts; |
| } |
| } |
| |
| if (kind <= 0) { /* identification failed */ |
| dev_info(&adapter->dev, |
| "Unsupported chip (man_id=0x%04X, " |
| "chip_id=0x%02X).\n", man_id, chip_id); |
| goto exit_free; |
| } |
| } |
| |
| /* We can fill in the remaining client fields. */ |
| strlcpy(new_client->name, "w83l785ts", I2C_NAME_SIZE); |
| data->valid = 0; |
| init_MUTEX(&data->update_lock); |
| |
| /* Default values in case the first read fails (unlikely). */ |
| data->temp_over = data->temp = 0; |
| |
| /* Tell the I2C layer a new client has arrived. */ |
| if ((err = i2c_attach_client(new_client))) |
| goto exit_free; |
| |
| /* |
| * Initialize the W83L785TS chip |
| * Nothing yet, assume it is already started. |
| */ |
| |
| /* Register sysfs hooks */ |
| data->class_dev = hwmon_device_register(&new_client->dev); |
| if (IS_ERR(data->class_dev)) { |
| err = PTR_ERR(data->class_dev); |
| goto exit_detach; |
| } |
| |
| device_create_file(&new_client->dev, &dev_attr_temp1_input); |
| device_create_file(&new_client->dev, &dev_attr_temp1_max); |
| |
| return 0; |
| |
| exit_detach: |
| i2c_detach_client(new_client); |
| exit_free: |
| kfree(data); |
| exit: |
| return err; |
| } |
| |
| static int w83l785ts_detach_client(struct i2c_client *client) |
| { |
| struct w83l785ts_data *data = i2c_get_clientdata(client); |
| int err; |
| |
| hwmon_device_unregister(data->class_dev); |
| |
| if ((err = i2c_detach_client(client))) { |
| dev_err(&client->dev, "Client deregistration failed, " |
| "client not detached.\n"); |
| return err; |
| } |
| |
| kfree(data); |
| return 0; |
| } |
| |
| static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval) |
| { |
| int value, i; |
| |
| /* 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(&client->dev, "Read 0x%02x from register " |
| "0x%02x.\n", value, reg); |
| return value; |
| } |
| dev_dbg(&client->dev, "Read failed, will retry in %d.\n", i); |
| msleep(i); |
| } |
| |
| dev_err(&client->dev, "Couldn't read value from register 0x%02x. " |
| "Please report.\n", 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); |
| |
| down(&data->update_lock); |
| |
| if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) { |
| dev_dbg(&client->dev, "Updating w83l785ts data.\n"); |
| data->temp = w83l785ts_read_value(client, |
| W83L785TS_REG_TEMP, data->temp); |
| data->temp_over = w83l785ts_read_value(client, |
| W83L785TS_REG_TEMP_OVER, data->temp_over); |
| |
| data->last_updated = jiffies; |
| data->valid = 1; |
| } |
| |
| up(&data->update_lock); |
| |
| return data; |
| } |
| |
| static int __init sensors_w83l785ts_init(void) |
| { |
| return i2c_add_driver(&w83l785ts_driver); |
| } |
| |
| static void __exit sensors_w83l785ts_exit(void) |
| { |
| i2c_del_driver(&w83l785ts_driver); |
| } |
| |
| MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); |
| MODULE_DESCRIPTION("W83L785TS-S driver"); |
| MODULE_LICENSE("GPL"); |
| |
| module_init(sensors_w83l785ts_init); |
| module_exit(sensors_w83l785ts_exit); |