hwmon: (lm77) Convert to a new-style i2c driver

The new-style lm77 driver implements the optional detect() callback
to cover the use cases of the legacy driver.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Andras Bali <drewie@freemail.hu>

1 files changed, 45 insertions, 57 deletions

diff --git a/drivers/hwmon/lm77.c b/drivers/hwmon/lm77.c
index 36d5a8c3ad8c..866b401ab6e8 100644
--- a/drivers/hwmon/lm77.c
+++ b/drivers/hwmon/lm77.c
@@ -52,7 +52,6 @@ I2C_CLIENT_INSMOD_1(lm77);
 
 /* Each client has this additional data */
 struct lm77_data {
-        struct i2c_client       client;
         struct device           *hwmon_dev;
         struct mutex            update_lock;
         char                    valid;
@@ -65,23 +64,35 @@ struct lm77_data {
         u8                      alarms;
 };
 
-static int lm77_attach_adapter(struct i2c_adapter *adapter);
-static int lm77_detect(struct i2c_adapter *adapter, int address, int kind);
+static int lm77_probe(struct i2c_client *client,
+                      const struct i2c_device_id *id);
+static int lm77_detect(struct i2c_client *client, int kind,
+                       struct i2c_board_info *info);
 static void lm77_init_client(struct i2c_client *client);
-static int lm77_detach_client(struct i2c_client *client);
+static int lm77_remove(struct i2c_client *client);
 static u16 lm77_read_value(struct i2c_client *client, u8 reg);
 static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value);
 
 static struct lm77_data *lm77_update_device(struct device *dev);
 
 
+static const struct i2c_device_id lm77_id[] = {
+        { "lm77", lm77 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, lm77_id);
+
 /* This is the driver that will be inserted */
 static struct i2c_driver lm77_driver = {
+        .class          = I2C_CLASS_HWMON,
         .driver = {
                 .name   = "lm77",
         },
-        .attach_adapter = lm77_attach_adapter,
-        .detach_client  = lm77_detach_client,
+        .probe          = lm77_probe,
+        .remove         = lm77_remove,
+        .id_table       = lm77_id,
+        .detect         = lm77_detect,
+        .address_data   = &addr_data,
 };
 
 /* straight from the datasheet */
@@ -215,13 +226,6 @@ static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 2);
 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 0);
 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 1);
 
-static int lm77_attach_adapter(struct i2c_adapter *adapter)
-{
-        if (!(adapter->class & I2C_CLASS_HWMON))
-                return 0;
-        return i2c_probe(adapter, &addr_data, lm77_detect);
-}
-
 static struct attribute *lm77_attributes[] = {
         &dev_attr_temp1_input.attr,
         &dev_attr_temp1_crit.attr,
@@ -240,32 +244,15 @@ static const struct attribute_group lm77_group = {
         .attrs = lm77_attributes,
 };
 
-/* This function is called by i2c_probe */
-static int lm77_detect(struct i2c_adapter *adapter, int address, int kind)
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int lm77_detect(struct i2c_client *new_client, int kind,
+                       struct i2c_board_info *info)
 {
-        struct i2c_client *new_client;
-        struct lm77_data *data;
-        int err = 0;
-        const char *name = "";
+        struct i2c_adapter *adapter = new_client->adapter;
 
         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 lm77_{read,write}_value. */
-        if (!(data = kzalloc(sizeof(struct lm77_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 = &lm77_driver;
-        new_client->flags = 0;
+                return -ENODEV;
 
         /* Here comes the remaining detection.  Since the LM77 has no
            register dedicated to identification, we have to rely on the
@@ -294,7 +281,7 @@ static int lm77_detect(struct i2c_adapter *adapter, int address, int kind)
                             || i2c_smbus_read_word_data(new_client, i + 3) != crit
                             || i2c_smbus_read_word_data(new_client, i + 4) != min
                             || i2c_smbus_read_word_data(new_client, i + 5) != max)
-                                goto exit_free;
+                                return -ENODEV;
 
                 /* sign bits */
                 if (((cur & 0x00f0) != 0xf0 && (cur & 0x00f0) != 0x0)
@@ -302,51 +289,55 @@ static int lm77_detect(struct i2c_adapter *adapter, int address, int kind)
                     || ((crit & 0x00f0) != 0xf0 && (crit & 0x00f0) != 0x0)
                     || ((min & 0x00f0) != 0xf0 && (min & 0x00f0) != 0x0)
                     || ((max & 0x00f0) != 0xf0 && (max & 0x00f0) != 0x0))
-                        goto exit_free;
+                        return -ENODEV;
 
                 /* unused bits */
                 if (conf & 0xe0)
-                        goto exit_free;
+                        return -ENODEV;
 
                 /* 0x06 and 0x07 return the last read value */
                 cur = i2c_smbus_read_word_data(new_client, 0);
                 if (i2c_smbus_read_word_data(new_client, 6) != cur
                     || i2c_smbus_read_word_data(new_client, 7) != cur)
-                        goto exit_free;
+                        return -ENODEV;
                 hyst = i2c_smbus_read_word_data(new_client, 2);
                 if (i2c_smbus_read_word_data(new_client, 6) != hyst
                     || i2c_smbus_read_word_data(new_client, 7) != hyst)
-                        goto exit_free;
+                        return -ENODEV;
                 min = i2c_smbus_read_word_data(new_client, 4);
                 if (i2c_smbus_read_word_data(new_client, 6) != min
                     || i2c_smbus_read_word_data(new_client, 7) != min)
-                        goto exit_free;
+                        return -ENODEV;
 
         }
 
-        /* Determine the chip type - only one kind supported! */
-        if (kind <= 0)
-                kind = lm77;
+        strlcpy(info->type, "lm77", I2C_NAME_SIZE);
 
-        if (kind == lm77) {
-                name = "lm77";
+        return 0;
+}
+
+static int lm77_probe(struct i2c_client *new_client,
+                      const struct i2c_device_id *id)
+{
+        struct lm77_data *data;
+        int err;
+
+        data = kzalloc(sizeof(struct lm77_data), GFP_KERNEL);
+        if (!data) {
+                err = -ENOMEM;
+                goto exit;
         }
 
-        /* Fill in the remaining client fields and put it into the global list */
-        strlcpy(new_client->name, name, I2C_NAME_SIZE);
+        i2c_set_clientdata(new_client, data);
         data->valid = 0;
         mutex_init(&data->update_lock);
 
-        /* Tell the I2C layer a new client has arrived */
-        if ((err = i2c_attach_client(new_client)))
-                goto exit_free;
-
         /* Initialize the LM77 chip */
         lm77_init_client(new_client);
 
         /* Register sysfs hooks */
         if ((err = sysfs_create_group(&new_client->dev.kobj, &lm77_group)))
-                goto exit_detach;
+                goto exit_free;
 
         data->hwmon_dev = hwmon_device_register(&new_client->dev);
         if (IS_ERR(data->hwmon_dev)) {
@@ -358,20 +349,17 @@ static int lm77_detect(struct i2c_adapter *adapter, int address, int kind)
 
 exit_remove:
         sysfs_remove_group(&new_client->dev.kobj, &lm77_group);
-exit_detach:
-        i2c_detach_client(new_client);
 exit_free:
         kfree(data);
 exit:
         return err;
 }
 
-static int lm77_detach_client(struct i2c_client *client)
+static int lm77_remove(struct i2c_client *client)
 {
         struct lm77_data *data = i2c_get_clientdata(client);
         hwmon_device_unregister(data->hwmon_dev);
         sysfs_remove_group(&client->dev.kobj, &lm77_group);
-        i2c_detach_client(client);
         kfree(data);
         return 0;
 }