drivers/i2c/chips/w83l785ts.c - arm/linux - Git at Google

 /*
  * 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/config.h>
 #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);
	/*
	* 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/config.h>
	#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);