hwmon: (lm78) Convert to a new-style i2c driver
authorJean Delvare <khali@linux-fr.org>
Fri, 17 Oct 2008 15:51:16 +0000 (17:51 +0200)
committerJean Delvare <khali@mahadeva.delvare>
Fri, 17 Oct 2008 15:51:16 +0000 (17:51 +0200)
The new-style lm78 driver implements the optional detect() callback
to cover the use cases of the legacy driver.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
drivers/hwmon/lm78.c

index 177eadd..b5e3b28 100644 (file)
@@ -115,7 +115,7 @@ static inline int TEMP_FROM_REG(s8 val)
 #define DIV_FROM_REG(val) (1 << (val))
 
 struct lm78_data {
-       struct i2c_client client;
+       struct i2c_client *client;
        struct device *hwmon_dev;
        struct mutex lock;
        enum chips type;
@@ -142,9 +142,11 @@ struct lm78_data {
 };
 
 
-static int lm78_attach_adapter(struct i2c_adapter *adapter);
-static int lm78_detect(struct i2c_adapter *adapter, int address, int kind);
-static int lm78_detach_client(struct i2c_client *client);
+static int lm78_i2c_detect(struct i2c_client *client, int kind,
+                          struct i2c_board_info *info);
+static int lm78_i2c_probe(struct i2c_client *client,
+                         const struct i2c_device_id *id);
+static int lm78_i2c_remove(struct i2c_client *client);
 
 static int __devinit lm78_isa_probe(struct platform_device *pdev);
 static int __devexit lm78_isa_remove(struct platform_device *pdev);
@@ -155,12 +157,23 @@ static struct lm78_data *lm78_update_device(struct device *dev);
 static void lm78_init_device(struct lm78_data *data);
 
 
+static const struct i2c_device_id lm78_i2c_id[] = {
+       { "lm78", lm78 },
+       { "lm79", lm79 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, lm78_i2c_id);
+
 static struct i2c_driver lm78_driver = {
+       .class          = I2C_CLASS_HWMON,
        .driver = {
                .name   = "lm78",
        },
-       .attach_adapter = lm78_attach_adapter,
-       .detach_client  = lm78_detach_client,
+       .probe          = lm78_i2c_probe,
+       .remove         = lm78_i2c_remove,
+       .id_table       = lm78_i2c_id,
+       .detect         = lm78_i2c_detect,
+       .address_data   = &addr_data,
 };
 
 static struct platform_driver lm78_isa_driver = {
@@ -445,29 +458,6 @@ static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
 static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO, show_alarm, NULL, 11);
 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
 
-/* This function is called when:
-     * lm78_driver is inserted (when this module is loaded), for each
-       available adapter
-     * when a new adapter is inserted (and lm78_driver is still present)
-   We block updates of the ISA device to minimize the risk of concurrent
-   access to the same LM78 chip through different interfaces. */
-static int lm78_attach_adapter(struct i2c_adapter *adapter)
-{
-       struct lm78_data *data;
-       int err;
-
-       if (!(adapter->class & I2C_CLASS_HWMON))
-               return 0;
-
-       data = pdev ? platform_get_drvdata(pdev) : NULL;
-       if (data)
-               mutex_lock(&data->update_lock);
-       err = i2c_probe(adapter, &addr_data, lm78_detect);
-       if (data)
-               mutex_unlock(&data->update_lock);
-       return err;
-}
-
 static struct attribute *lm78_attributes[] = {
        &sensor_dev_attr_in0_input.dev_attr.attr,
        &sensor_dev_attr_in0_min.dev_attr.attr,
@@ -537,13 +527,11 @@ static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
 /* Returns 1 if the I2C chip appears to be an alias of the ISA chip */
 static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
 {
-       struct lm78_data *i2c, *isa;
+       struct lm78_data *isa;
        int i;
 
        if (!pdev)      /* No ISA chip */
                return 0;
-
-       i2c = i2c_get_clientdata(client);
        isa = platform_get_drvdata(pdev);
 
        if (lm78_read_value(isa, LM78_REG_I2C_ADDR) != client->addr)
@@ -554,70 +542,55 @@ static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
        /* We compare all the limit registers, the config register and the
         * interrupt mask registers */
        for (i = 0x2b; i <= 0x3d; i++) {
-               if (lm78_read_value(isa, i) != lm78_read_value(i2c, i))
+               if (lm78_read_value(isa, i) !=
+                   i2c_smbus_read_byte_data(client, i))
                        return 0;
        }
        if (lm78_read_value(isa, LM78_REG_CONFIG) !=
-           lm78_read_value(i2c, LM78_REG_CONFIG))
+           i2c_smbus_read_byte_data(client, LM78_REG_CONFIG))
                return 0;
        for (i = 0x43; i <= 0x46; i++) {
-               if (lm78_read_value(isa, i) != lm78_read_value(i2c, i))
+               if (lm78_read_value(isa, i) !=
+                   i2c_smbus_read_byte_data(client, i))
                        return 0;
        }
 
        return 1;
 }
 
-/* This function is called by i2c_probe */
-static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
+static int lm78_i2c_detect(struct i2c_client *client, int kind,
+                          struct i2c_board_info *info)
 {
-       int i, err;
-       struct i2c_client *new_client;
-       struct lm78_data *data;
-       const char *client_name = "";
-
-       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
-               err = -ENODEV;
-               goto ERROR1;
-       }
-
-       /* 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 lm78_{read,write}_value. */
+       int i;
+       struct lm78_data *isa = pdev ? platform_get_drvdata(pdev) : NULL;
+       const char *client_name;
+       struct i2c_adapter *adapter = client->adapter;
+       int address = client->addr;
 
-       if (!(data = kzalloc(sizeof(struct lm78_data), GFP_KERNEL))) {
-               err = -ENOMEM;
-               goto ERROR1;
-       }
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+               return -ENODEV;
 
-       new_client = &data->client;
-       i2c_set_clientdata(new_client, data);
-       new_client->addr = address;
-       new_client->adapter = adapter;
-       new_client->driver = &lm78_driver;
+       /* We block updates of the ISA device to minimize the risk of
+          concurrent access to the same LM78 chip through different
+          interfaces. */
+       if (isa)
+               mutex_lock(&isa->update_lock);
 
-       /* Now, we do the remaining detection. */
        if (kind < 0) {
-               if (lm78_read_value(data, LM78_REG_CONFIG) & 0x80) {
-                       err = -ENODEV;
-                       goto ERROR2;
-               }
-               if (lm78_read_value(data, LM78_REG_I2C_ADDR) !=
-                   address) {
-                       err = -ENODEV;
-                       goto ERROR2;
-               }
+               if ((i2c_smbus_read_byte_data(client, LM78_REG_CONFIG) & 0x80)
+                || i2c_smbus_read_byte_data(client, LM78_REG_I2C_ADDR)
+                   != address)
+                       goto err_nodev;
+
                /* Explicitly prevent the misdetection of Winbond chips */
-               i = lm78_read_value(data, 0x4f);
-               if (i == 0xa3 || i == 0x5c) {
-                       err = -ENODEV;
-                       goto ERROR2;
-               }
+               i = i2c_smbus_read_byte_data(client, 0x4f);
+               if (i == 0xa3 || i == 0x5c)
+                       goto err_nodev;
        }
 
        /* Determine the chip type. */
        if (kind <= 0) {
-               i = lm78_read_value(data, LM78_REG_CHIPID);
+               i = i2c_smbus_read_byte_data(client, LM78_REG_CHIPID);
                if (i == 0x00 || i == 0x20      /* LM78 */
                 || i == 0x40)                  /* LM78-J */
                        kind = lm78;
@@ -629,40 +602,59 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
                                        "parameter for unknown chip at "
                                        "adapter %d, address 0x%02x\n",
                                        i2c_adapter_id(adapter), address);
-                       err = -ENODEV;
-                       goto ERROR2;
+                       goto err_nodev;
                }
 
-               if (lm78_alias_detect(new_client, i)) {
+               if (lm78_alias_detect(client, i)) {
                        dev_dbg(&adapter->dev, "Device at 0x%02x appears to "
                                "be the same as ISA device\n", address);
-                       err = -ENODEV;
-                       goto ERROR2;
+                       goto err_nodev;
                }
        }
 
-       if (kind == lm78) {
-               client_name = "lm78";
-       } else if (kind == lm79) {
+       if (isa)
+               mutex_unlock(&isa->update_lock);
+
+       switch (kind) {
+       case lm79:
                client_name = "lm79";
+               break;
+       default:
+               client_name = "lm78";
        }
+       strlcpy(info->type, client_name, I2C_NAME_SIZE);
 
-       /* Fill in the remaining client fields and put into the global list */
-       strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
-       data->type = kind;
+       return 0;
 
-       /* Tell the I2C layer a new client has arrived */
-       if ((err = i2c_attach_client(new_client)))
-               goto ERROR2;
+ err_nodev:
+       if (isa)
+               mutex_unlock(&isa->update_lock);
+       return -ENODEV;
+}
+
+static int lm78_i2c_probe(struct i2c_client *client,
+                         const struct i2c_device_id *id)
+{
+       struct lm78_data *data;
+       int err;
+
+       data = kzalloc(sizeof(struct lm78_data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       i2c_set_clientdata(client, data);
+       data->client = client;
+       data->type = id->driver_data;
 
        /* Initialize the LM78 chip */
        lm78_init_device(data);
 
        /* Register sysfs hooks */
-       if ((err = sysfs_create_group(&new_client->dev.kobj, &lm78_group)))
+       err = sysfs_create_group(&client->dev.kobj, &lm78_group);
+       if (err)
                goto ERROR3;
 
-       data->hwmon_dev = hwmon_device_register(&new_client->dev);
+       data->hwmon_dev = hwmon_device_register(&client->dev);
        if (IS_ERR(data->hwmon_dev)) {
                err = PTR_ERR(data->hwmon_dev);
                goto ERROR4;
@@ -671,26 +663,18 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
        return 0;
 
 ERROR4:
-       sysfs_remove_group(&new_client->dev.kobj, &lm78_group);
+       sysfs_remove_group(&client->dev.kobj, &lm78_group);
 ERROR3:
-       i2c_detach_client(new_client);
-ERROR2:
        kfree(data);
-ERROR1:
        return err;
 }
 
-static int lm78_detach_client(struct i2c_client *client)
+static int lm78_i2c_remove(struct i2c_client *client)
 {
        struct lm78_data *data = i2c_get_clientdata(client);
-       int err;
 
        hwmon_device_unregister(data->hwmon_dev);
        sysfs_remove_group(&client->dev.kobj, &lm78_group);
-
-       if ((err = i2c_detach_client(client)))
-               return err;
-
        kfree(data);
 
        return 0;
@@ -774,9 +758,9 @@ static int __devexit lm78_isa_remove(struct platform_device *pdev)
    would slow down the LM78 access and should not be necessary.  */
 static int lm78_read_value(struct lm78_data *data, u8 reg)
 {
-       struct i2c_client *client = &data->client;
+       struct i2c_client *client = data->client;
 
-       if (!client->driver) { /* ISA device */
+       if (!client) { /* ISA device */
                int res;
                mutex_lock(&data->lock);
                outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
@@ -796,9 +780,9 @@ static int lm78_read_value(struct lm78_data *data, u8 reg)
    nowhere else be necessary! */
 static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value)
 {
-       struct i2c_client *client = &data->client;
+       struct i2c_client *client = data->client;
 
-       if (!client->driver) { /* ISA device */
+       if (!client) { /* ISA device */
                mutex_lock(&data->lock);
                outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
                outb_p(value, data->isa_addr + LM78_DATA_REG_OFFSET);