hwmon: (lm78) Convert to a new-style i2c driver

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>

1 files changed, 89 insertions, 105 deletions

diff --git a/drivers/hwmon/lm78.c b/drivers/hwmon/lm78.c
index 177eaddde321..b5e3b2851698 100644
--- a/drivers/hwmon/lm78.c
+++ b/drivers/hwmon/lm78.c
@@ -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);