hwmon: (ads2828) Only keep data in device data structure if needed

The variables diff_input, ext_vref, and vref_mv are only used in the probe
function and therefore don't need to be kept in the device data structure.

Reviewed-and-Tested-by: Robert Rosengren <robert.rosengren@axis.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index 071f779..bce4e9f 100644 (file)
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -49,9 +49,6 @@ enum ads7828_chips { ads7828, ads7830 };
 /* Client specific data */
 struct ads7828_data {
        struct regmap *regmap;
-       bool diff_input;                /* Differential input */
-       bool ext_vref;                  /* External voltage reference */
-       unsigned int vref_mv;           /* voltage reference value */
        u8 cmd_byte;                    /* Command byte without channel bits */
        unsigned int lsb_resol;         /* Resolution of the ADC sample LSB */
 };
@@ -120,39 +117,38 @@ static int ads7828_probe(struct i2c_client *client,
        struct ads7828_platform_data *pdata = dev_get_platdata(dev);
        struct ads7828_data *data;
        struct device *hwmon_dev;
+       unsigned int vref_mv = ADS7828_INT_VREF_MV;
+       bool diff_input = false;
+       bool ext_vref = false;
 
        data = devm_kzalloc(dev, sizeof(struct ads7828_data), GFP_KERNEL);
        if (!data)
                return -ENOMEM;
 
        if (pdata) {
-               data->diff_input = pdata->diff_input;
-               data->ext_vref = pdata->ext_vref;
-               if (data->ext_vref)
-                       data->vref_mv = pdata->vref_mv;
+               diff_input = pdata->diff_input;
+               ext_vref = pdata->ext_vref;
+               if (ext_vref && pdata->vref_mv)
+                       vref_mv = pdata->vref_mv;
        }
 
-       /* Bound Vref with min/max values if it was provided */
-       if (data->vref_mv)
-               data->vref_mv = clamp_val(data->vref_mv,
-                                         ADS7828_EXT_VREF_MV_MIN,
-                                         ADS7828_EXT_VREF_MV_MAX);
-       else
-               data->vref_mv = ADS7828_INT_VREF_MV;
+       /* Bound Vref with min/max values */
+       vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN,
+                           ADS7828_EXT_VREF_MV_MAX);
 
        /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
        if (id->driver_data == ads7828) {
-               data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+               data->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 4096);
                data->regmap = devm_regmap_init_i2c(client,
                                                    &ads2828_regmap_config);
        } else {
-               data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
+               data->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 256);
                data->regmap = devm_regmap_init_i2c(client,
                                                    &ads2830_regmap_config);
        }
 
-       data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
-       if (!data->diff_input)
+       data->cmd_byte = ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
+       if (!diff_input)
                data->cmd_byte |= ADS7828_CMD_SD_SE;
 
        hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,