1 files changed, 329 insertions, 0 deletions

diff --git a/drivers/i2c/chips/w83l785ts.c b/drivers/i2c/chips/w83l785ts.c
new file mode 100644
index 000000000000..59bbc5881fa6
--- /dev/null
+++ b/drivers/i2c/chips/w83l785ts.c
@@ -0,0 +1,329 @@
+/*
+ * 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, 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, 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);