|  | /* | 
|  | * 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> | 
|  |  | 
|  | /* 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 }; | 
|  | static unsigned int normal_isa[] = { I2C_CLIENT_ISA_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 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 */ | 
|  | device_create_file(&new_client->dev, &dev_attr_temp1_input); | 
|  | device_create_file(&new_client->dev, &dev_attr_temp1_max); | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | exit_free: | 
|  | kfree(data); | 
|  | exit: | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static int w83l785ts_detach_client(struct i2c_client *client) | 
|  | { | 
|  | int err; | 
|  |  | 
|  | if ((err = i2c_detach_client(client))) { | 
|  | dev_err(&client->dev, "Client deregistration failed, " | 
|  | "client not detached.\n"); | 
|  | return err; | 
|  | } | 
|  |  | 
|  | kfree(i2c_get_clientdata(client)); | 
|  | 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); |