--- /dev/null
+/*
+ * 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.
+ *
+ * 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/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,
+ const struct i2c_device_id *id);
+static int w83l785ts_detect(struct i2c_client *client,
+ struct i2c_board_info *info);
+static int 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", 0 },
+ { }
+};
+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;
+ char valid; /* zero 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;
+ }
+
+ strlcpy(info->type, "w83l785ts", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+static int w83l785ts_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ 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 int 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);
+
+ return 0;
+}
+
+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 = 1;
+ }
+
+ 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");
Code Review / kvmfornfv.git / blobdiff