hwmon: (ads7828) Convert to a new-style i2c driver

The new-style ads7828 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, 38 insertions, 51 deletions

diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index 5c8b6e0..5c39b4a 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -64,7 +64,6 @@ static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
 
 /* Each client has this additional data */
 struct ads7828_data {
-	struct i2c_client client;
 	struct device *hwmon_dev;
 	struct mutex update_lock; /* mutex protect updates */
 	char valid; /* !=0 if following fields are valid */
@@ -73,7 +72,10 @@ struct ads7828_data {
 };
 
 /* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_adapter *adapter, int address, int kind);
+static int ads7828_detect(struct i2c_client *client, int kind,
+			  struct i2c_board_info *info);
+static int ads7828_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id);
 
 /* The ADS7828 returns the 12-bit sample in two bytes,
 	these are read as a word then byte-swapped */
@@ -156,58 +158,43 @@ static const struct attribute_group ads7828_group = {
 	.attrs = ads7828_attributes,
 };
 
-static int ads7828_attach_adapter(struct i2c_adapter *adapter)
-{
-	if (!(adapter->class & I2C_CLASS_HWMON))
-		return 0;
-	return i2c_probe(adapter, &addr_data, ads7828_detect);
-}
-
-static int ads7828_detach_client(struct i2c_client *client)
+static int ads7828_remove(struct i2c_client *client)
 {
 	struct ads7828_data *data = i2c_get_clientdata(client);
 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&client->dev.kobj, &ads7828_group);
-	i2c_detach_client(client);
 	kfree(i2c_get_clientdata(client));
 	return 0;
 }
 
+static const struct i2c_device_id ads7828_id[] = {
+	{ "ads7828", ads7828 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_id);
+
 /* This is the driver that will be inserted */
 static struct i2c_driver ads7828_driver = {
+	.class = I2C_CLASS_HWMON,
 	.driver = {
 		.name = "ads7828",
 	},
-	.attach_adapter = ads7828_attach_adapter,
-	.detach_client = ads7828_detach_client,
+	.probe = ads7828_probe,
+	.remove = ads7828_remove,
+	.id_table = ads7828_id,
+	.detect = ads7828_detect,
+	.address_data = &addr_data,
 };
 
-/* This function is called by i2c_probe */
-static int ads7828_detect(struct i2c_adapter *adapter, int address, int kind)
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int ads7828_detect(struct i2c_client *client, int kind,
+			  struct i2c_board_info *info)
 {
-	struct i2c_client *client;
-	struct ads7828_data *data;
-	int err = 0;
-	const char *name = "";
+	struct i2c_adapter *adapter = client->adapter;
 
 	/* Check we have a valid client */
 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_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 ads7828_read_value. */
-	data = kzalloc(sizeof(struct ads7828_data), GFP_KERNEL);
-	if (!data) {
-		err = -ENOMEM;
-		goto exit;
-	}
-
-	client = &data->client;
-	i2c_set_clientdata(client, data);
-	client->addr = address;
-	client->adapter = adapter;
-	client->driver = &ads7828_driver;
+		return -ENODEV;
 
 	/* Now, we do the remaining detection. There is no identification
 	dedicated register so attempt to sanity check using knowledge of
@@ -225,32 +212,34 @@ static int ads7828_detect(struct i2c_adapter *adapter, int address, int kind)
 				printk(KERN_DEBUG
 				"%s : Doesn't look like an ads7828 device\n",
 				__func__);
-				goto exit_free;
+				return -ENODEV;
 			}
 		}
 	}
+	strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
 
-	/* Determine the chip type - only one kind supported! */
-	if (kind <= 0)
-		kind = ads7828;
+	return 0;
+}
 
-	if (kind == ads7828)
-		name = "ads7828";
+static int ads7828_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct ads7828_data *data;
+	int err;
 
-	/* Fill in the remaining client fields, put it into the global list */
-	strlcpy(client->name, name, I2C_NAME_SIZE);
+	data = kzalloc(sizeof(struct ads7828_data), GFP_KERNEL);
+	if (!data) {
+		err = -ENOMEM;
+		goto exit;
+	}
 
+	i2c_set_clientdata(client, data);
 	mutex_init(&data->update_lock);
 
-	/* Tell the I2C layer a new client has arrived */
-	err = i2c_attach_client(client);
-	if (err)
-		goto exit_free;
-
 	/* Register sysfs hooks */
 	err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
 	if (err)
-		goto exit_detach;
+		goto exit_free;
 
 	data->hwmon_dev = hwmon_device_register(&client->dev);
 	if (IS_ERR(data->hwmon_dev)) {
@@ -262,8 +251,6 @@ static int ads7828_detect(struct i2c_adapter *adapter, int address, int kind)
 
 exit_remove:
 	sysfs_remove_group(&client->dev.kobj, &ads7828_group);
-exit_detach:
-	i2c_detach_client(client);
 exit_free:
 	kfree(data);
 exit: