hwmon: driver for Texas Instruments amc6821 chip
[safe/jmp/linux-2.6] / drivers / hwmon / lm75.c
index a40166f..8ae2cfe 100644 (file)
 #include "lm75.h"
 
 
-/* Addresses to scan */
-static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
-                                       0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
+/*
+ * This driver handles the LM75 and compatible digital temperature sensors.
+ */
+
+enum lm75_type {               /* keep sorted in alphabetical order */
+       ds1775,
+       ds75,
+       lm75,
+       lm75a,
+       max6625,
+       max6626,
+       mcp980x,
+       stds75,
+       tcn75,
+       tmp100,
+       tmp101,
+       tmp175,
+       tmp275,
+       tmp75,
+};
 
-/* Insmod parameters */
-I2C_CLIENT_INSMOD_1(lm75);
+/* Addresses scanned */
+static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
+                                       0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
 
-/* Many LM75 constants specified below */
 
 /* The LM75 registers */
 #define LM75_REG_CONF          0x01
@@ -49,10 +66,10 @@ static const u8 LM75_REG_TEMP[3] = {
 
 /* Each client has this additional data */
 struct lm75_data {
-       struct i2c_client       client;
-       struct class_device *class_dev;
+       struct device           *hwmon_dev;
        struct mutex            update_lock;
-       char                    valid;          /* !=0 if following fields are valid */
+       u8                      orig_conf;
+       char                    valid;          /* !=0 if registers are valid */
        unsigned long           last_updated;   /* In jiffies */
        u16                     temp[3];        /* Register values,
                                                   0 = input
@@ -60,24 +77,14 @@ struct lm75_data {
                                                   2 = hyst */
 };
 
-static int lm75_attach_adapter(struct i2c_adapter *adapter);
-static int lm75_detect(struct i2c_adapter *adapter, int address, int kind);
-static void lm75_init_client(struct i2c_client *client);
-static int lm75_detach_client(struct i2c_client *client);
 static int lm75_read_value(struct i2c_client *client, u8 reg);
 static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
 static struct lm75_data *lm75_update_device(struct device *dev);
 
 
-/* This is the driver that will be inserted */
-static struct i2c_driver lm75_driver = {
-       .driver = {
-               .name   = "lm75",
-       },
-       .id             = I2C_DRIVERID_LM75,
-       .attach_adapter = lm75_attach_adapter,
-       .detach_client  = lm75_detach_client,
-};
+/*-----------------------------------------------------------------------*/
+
+/* sysfs attributes for hwmon */
 
 static ssize_t show_temp(struct device *dev, struct device_attribute *da,
                         char *buf)
@@ -95,7 +102,7 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *da,
        struct i2c_client *client = to_i2c_client(dev);
        struct lm75_data *data = i2c_get_clientdata(client);
        int nr = attr->index;
-       unsigned long temp = simple_strtoul(buf, NULL, 10);
+       long temp = simple_strtol(buf, NULL, 10);
 
        mutex_lock(&data->update_lock);
        data->temp[nr] = LM75_TEMP_TO_REG(temp);
@@ -110,13 +117,6 @@ static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
                        show_temp, set_temp, 2);
 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 
-static int lm75_attach_adapter(struct i2c_adapter *adapter)
-{
-       if (!(adapter->class & I2C_CLASS_HWMON))
-               return 0;
-       return i2c_probe(adapter, &addr_data, lm75_detect);
-}
-
 static struct attribute *lm75_attributes[] = {
        &sensor_dev_attr_temp1_input.dev_attr.attr,
        &sensor_dev_attr_temp1_max.dev_attr.attr,
@@ -129,138 +129,187 @@ static const struct attribute_group lm75_group = {
        .attrs = lm75_attributes,
 };
 
-/* This function is called by i2c_probe */
-static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
-{
-       int i;
-       struct i2c_client *new_client;
-       struct lm75_data *data;
-       int err = 0;
-       const char *name = "";
-
-       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
-                                    I2C_FUNC_SMBUS_WORD_DATA))
-               goto exit;
-
-       /* OK. For now, we presume we have a valid client. We now create the
-          client structure, even though we cannot fill it completely yet.
-          But it allows us to access lm75_{read,write}_value. */
-       if (!(data = kzalloc(sizeof(struct lm75_data), GFP_KERNEL))) {
-               err = -ENOMEM;
-               goto exit;
-       }
+/*-----------------------------------------------------------------------*/
 
-       new_client = &data->client;
-       i2c_set_clientdata(new_client, data);
-       new_client->addr = address;
-       new_client->adapter = adapter;
-       new_client->driver = &lm75_driver;
-       new_client->flags = 0;
+/* device probe and removal */
 
-       /* Now, we do the remaining detection. There is no identification-
-          dedicated register so we have to rely on several tricks:
-          unused bits, registers cycling over 8-address boundaries,
-          addresses 0x04-0x07 returning the last read value.
-          The cycling+unused addresses combination is not tested,
-          since it would significantly slow the detection down and would
-          hardly add any value. */
-       if (kind < 0) {
-               int cur, conf, hyst, os;
-
-               /* Unused addresses */
-               cur = i2c_smbus_read_word_data(new_client, 0);
-               conf = i2c_smbus_read_byte_data(new_client, 1);
-               hyst = i2c_smbus_read_word_data(new_client, 2);
-               if (i2c_smbus_read_word_data(new_client, 4) != hyst
-                || i2c_smbus_read_word_data(new_client, 5) != hyst
-                || i2c_smbus_read_word_data(new_client, 6) != hyst
-                || i2c_smbus_read_word_data(new_client, 7) != hyst)
-                       goto exit_free;
-               os = i2c_smbus_read_word_data(new_client, 3);
-               if (i2c_smbus_read_word_data(new_client, 4) != os
-                || i2c_smbus_read_word_data(new_client, 5) != os
-                || i2c_smbus_read_word_data(new_client, 6) != os
-                || i2c_smbus_read_word_data(new_client, 7) != os)
-                       goto exit_free;
-
-               /* Unused bits */
-               if (conf & 0xe0)
-                       goto exit_free;
-
-               /* Addresses cycling */
-               for (i = 8; i < 0xff; i += 8)
-                       if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
-                        || i2c_smbus_read_word_data(new_client, i + 2) != hyst
-                        || i2c_smbus_read_word_data(new_client, i + 3) != os)
-                               goto exit_free;
-       }
+static int
+lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+       struct lm75_data *data;
+       int status;
+       u8 set_mask, clr_mask;
+       int new;
 
-       /* Determine the chip type - only one kind supported! */
-       if (kind <= 0)
-               kind = lm75;
+       if (!i2c_check_functionality(client->adapter,
+                       I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
+               return -EIO;
 
-       if (kind == lm75) {
-               name = "lm75";
-       }
+       data = kzalloc(sizeof(struct lm75_data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
 
-       /* Fill in the remaining client fields and put it into the global list */
-       strlcpy(new_client->name, name, I2C_NAME_SIZE);
-       data->valid = 0;
+       i2c_set_clientdata(client, data);
        mutex_init(&data->update_lock);
 
-       /* Tell the I2C layer a new client has arrived */
-       if ((err = i2c_attach_client(new_client)))
+       /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
+        * Then tweak to be more precise when appropriate.
+        */
+       set_mask = 0;
+       clr_mask = (1 << 0)                     /* continuous conversions */
+               | (1 << 6) | (1 << 5);          /* 9-bit mode */
+
+       /* configure as specified */
+       status = lm75_read_value(client, LM75_REG_CONF);
+       if (status < 0) {
+               dev_dbg(&client->dev, "Can't read config? %d\n", status);
                goto exit_free;
+       }
+       data->orig_conf = status;
+       new = status & ~clr_mask;
+       new |= set_mask;
+       if (status != new)
+               lm75_write_value(client, LM75_REG_CONF, new);
+       dev_dbg(&client->dev, "Config %02x\n", new);
 
-       /* Initialize the LM75 chip */
-       lm75_init_client(new_client);
-       
        /* Register sysfs hooks */
-       if ((err = sysfs_create_group(&new_client->dev.kobj, &lm75_group)))
-               goto exit_detach;
+       status = sysfs_create_group(&client->dev.kobj, &lm75_group);
+       if (status)
+               goto exit_free;
 
-       data->class_dev = hwmon_device_register(&new_client->dev);
-       if (IS_ERR(data->class_dev)) {
-               err = PTR_ERR(data->class_dev);
+       data->hwmon_dev = hwmon_device_register(&client->dev);
+       if (IS_ERR(data->hwmon_dev)) {
+               status = PTR_ERR(data->hwmon_dev);
                goto exit_remove;
        }
 
+       dev_info(&client->dev, "%s: sensor '%s'\n",
+                dev_name(data->hwmon_dev), client->name);
+
        return 0;
 
 exit_remove:
-       sysfs_remove_group(&new_client->dev.kobj, &lm75_group);
-exit_detach:
-       i2c_detach_client(new_client);
+       sysfs_remove_group(&client->dev.kobj, &lm75_group);
 exit_free:
+       i2c_set_clientdata(client, NULL);
        kfree(data);
-exit:
-       return err;
+       return status;
 }
 
-static int lm75_detach_client(struct i2c_client *client)
+static int lm75_remove(struct i2c_client *client)
 {
        struct lm75_data *data = i2c_get_clientdata(client);
-       hwmon_device_unregister(data->class_dev);
+
+       hwmon_device_unregister(data->hwmon_dev);
        sysfs_remove_group(&client->dev.kobj, &lm75_group);
-       i2c_detach_client(client);
+       lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
+       i2c_set_clientdata(client, NULL);
        kfree(data);
        return 0;
 }
 
+static const struct i2c_device_id lm75_ids[] = {
+       { "ds1775", ds1775, },
+       { "ds75", ds75, },
+       { "lm75", lm75, },
+       { "lm75a", lm75a, },
+       { "max6625", max6625, },
+       { "max6626", max6626, },
+       { "mcp980x", mcp980x, },
+       { "stds75", stds75, },
+       { "tcn75", tcn75, },
+       { "tmp100", tmp100, },
+       { "tmp101", tmp101, },
+       { "tmp175", tmp175, },
+       { "tmp275", tmp275, },
+       { "tmp75", tmp75, },
+       { /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i2c, lm75_ids);
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int lm75_detect(struct i2c_client *new_client,
+                      struct i2c_board_info *info)
+{
+       struct i2c_adapter *adapter = new_client->adapter;
+       int i;
+       int cur, conf, hyst, os;
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+                                    I2C_FUNC_SMBUS_WORD_DATA))
+               return -ENODEV;
+
+       /* Now, we do the remaining detection. There is no identification-
+          dedicated register so we have to rely on several tricks:
+          unused bits, registers cycling over 8-address boundaries,
+          addresses 0x04-0x07 returning the last read value.
+          The cycling+unused addresses combination is not tested,
+          since it would significantly slow the detection down and would
+          hardly add any value. */
+
+       /* Unused addresses */
+       cur = i2c_smbus_read_word_data(new_client, 0);
+       conf = i2c_smbus_read_byte_data(new_client, 1);
+       hyst = i2c_smbus_read_word_data(new_client, 2);
+       if (i2c_smbus_read_word_data(new_client, 4) != hyst
+        || i2c_smbus_read_word_data(new_client, 5) != hyst
+        || i2c_smbus_read_word_data(new_client, 6) != hyst
+        || i2c_smbus_read_word_data(new_client, 7) != hyst)
+               return -ENODEV;
+       os = i2c_smbus_read_word_data(new_client, 3);
+       if (i2c_smbus_read_word_data(new_client, 4) != os
+        || i2c_smbus_read_word_data(new_client, 5) != os
+        || i2c_smbus_read_word_data(new_client, 6) != os
+        || i2c_smbus_read_word_data(new_client, 7) != os)
+               return -ENODEV;
+
+       /* Unused bits */
+       if (conf & 0xe0)
+               return -ENODEV;
+
+       /* Addresses cycling */
+       for (i = 8; i < 0xff; i += 8) {
+               if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
+                || i2c_smbus_read_word_data(new_client, i + 2) != hyst
+                || i2c_smbus_read_word_data(new_client, i + 3) != os)
+                       return -ENODEV;
+       }
+
+       strlcpy(info->type, "lm75", I2C_NAME_SIZE);
+
+       return 0;
+}
+
+static struct i2c_driver lm75_driver = {
+       .class          = I2C_CLASS_HWMON,
+       .driver = {
+               .name   = "lm75",
+       },
+       .probe          = lm75_probe,
+       .remove         = lm75_remove,
+       .id_table       = lm75_ids,
+       .detect         = lm75_detect,
+       .address_list   = normal_i2c,
+};
+
+/*-----------------------------------------------------------------------*/
+
+/* register access */
+
 /* All registers are word-sized, except for the configuration register.
    LM75 uses a high-byte first convention, which is exactly opposite to
-   the usual practice. */
+   the SMBus standard. */
 static int lm75_read_value(struct i2c_client *client, u8 reg)
 {
+       int value;
+
        if (reg == LM75_REG_CONF)
                return i2c_smbus_read_byte_data(client, reg);
-       else
-               return swab16(i2c_smbus_read_word_data(client, reg));
+
+       value = i2c_smbus_read_word_data(client, reg);
+       return (value < 0) ? value : swab16(value);
 }
 
-/* All registers are word-sized, except for the configuration register.
-   LM75 uses a high-byte first convention, which is exactly opposite to
-   the usual practice. */
 static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
 {
        if (reg == LM75_REG_CONF)
@@ -269,16 +318,6 @@ static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
                return i2c_smbus_write_word_data(client, reg, swab16(value));
 }
 
-static void lm75_init_client(struct i2c_client *client)
-{
-       int reg;
-
-       /* Enable if in shutdown mode */
-       reg = lm75_read_value(client, LM75_REG_CONF);
-       if (reg >= 0 && (reg & 0x01))
-               lm75_write_value(client, LM75_REG_CONF, reg & 0xfe);
-}
-
 static struct lm75_data *lm75_update_device(struct device *dev)
 {
        struct i2c_client *client = to_i2c_client(dev);
@@ -291,9 +330,16 @@ static struct lm75_data *lm75_update_device(struct device *dev)
                int i;
                dev_dbg(&client->dev, "Starting lm75 update\n");
 
-               for (i = 0; i < ARRAY_SIZE(data->temp); i++)
-                       data->temp[i] = lm75_read_value(client,
-                                                       LM75_REG_TEMP[i]);
+               for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
+                       int status;
+
+                       status = lm75_read_value(client, LM75_REG_TEMP[i]);
+                       if (status < 0)
+                               dev_dbg(&client->dev, "reg %d, err %d\n",
+                                               LM75_REG_TEMP[i], status);
+                       else
+                               data->temp[i] = status;
+               }
                data->last_updated = jiffies;
                data->valid = 1;
        }
@@ -303,6 +349,10 @@ static struct lm75_data *lm75_update_device(struct device *dev)
        return data;
 }
 
+/*-----------------------------------------------------------------------*/
+
+/* module glue */
+
 static int __init sensors_lm75_init(void)
 {
        return i2c_add_driver(&lm75_driver);