[PATCH 2/4] hwmon: (lm75) Create function from code to write into registers

[Iker Perez]

From: Iker Perez del Palomar Sustatxa <iker.pe...@codethink.co.uk>

Wrap the existing code to write configurations into registers in
a function.

Added error handling to the function.

Signed-off-by: Iker Perez del Palomar Sustatxa <iker.pe...@codethink.co.uk>
---
 drivers/hwmon/lm75.c | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index 1c012301b6ca..477ac0732ddf 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -228,6 +228,27 @@ static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
        return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
 }
 
+static int lm75_write_config(struct lm75_data *data, u8 set_mask,
+                            u8 clr_mask)
+{
+       u8 value;
+
+       clr_mask |= LM75_SHUTDOWN;
+       value = data->current_conf & ~clr_mask;
+       value |= set_mask;
+
+       if (data->current_conf != value) {
+               s32 err;
+
+               err = i2c_smbus_write_byte_data(data->client, LM75_REG_CONF,
+                                               value);
+               if (err)
+                       return err;
+               data->current_conf = value;
+       }
+       return 0;
+}
+
 static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
                     u32 attr, int channel, long *val)
 {
@@ -389,7 +410,6 @@ lm75_probe(struct i2c_client *client, const struct 
i2c_device_id *id)
        struct device *hwmon_dev;
        struct lm75_data *data;
        int status, err;
-       int new;
        enum lm75_type kind;
 
        if (client->dev.of_node)
@@ -429,16 +449,16 @@ lm75_probe(struct i2c_client *client, const struct 
i2c_device_id *id)
                return status;
        }
        data->orig_conf = status;
-       new = status & ~(data->params->clr_mask | LM75_SHUTDOWN);
-       new |= data->params->set_mask;
-       if (status != new)
-               i2c_smbus_write_byte_data(client, LM75_REG_CONF, new);
+       data->current_conf = status;
 
-       err = devm_add_action_or_reset(dev, lm75_remove, data);
+       err = lm75_write_config(data, data->params->set_mask,
+                               data->params->clr_mask);
        if (err)
                return err;
 
-       dev_dbg(dev, "Config %02x\n", new);
+       err = devm_add_action_or_reset(dev, lm75_remove, data);
+       if (err)
+               return err;
 
        hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
                                                         data, &lm75_chip_info,
-- 
2.11.0