iio:chemical:bme680: Tidy up parameters to regmap_bulk_read

A mixture of:
* Unnecessary casts of val parameter to u8 * which makes little sense as
  the function take a void *.
* Explicit sizes where we can use the destination type to define that.
  Note that's not true in all cases as we do read 3 bytes into 4 byte
  destinations.

Note that noting was broken here, I'm just trying to ensure this doesn't
get cut and paste into more drivers so cleaning these out subsystem wide.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Himanshu Jha <himanshujha199640@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>

drivers/iio/chemical/bme680_core.c

@@ -114,14 +114,16 @@ static int bme680_read_calib(struct bme680_data *data,
 	__le16 buf;
 
 	/* Temperature related coefficients */
-	ret = regmap_bulk_read(data->regmap, BME680_T1_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_T1_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_T1_LSB_REG\n");
 		return ret;
 	}
 	calib->par_t1 = le16_to_cpu(buf);
 
-	ret = regmap_bulk_read(data->regmap, BME680_T2_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_T2_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_T2_LSB_REG\n");
 		return ret;
@@ -136,14 +138,16 @@ static int bme680_read_calib(struct bme680_data *data,
 	calib->par_t3 = tmp;
 
 	/* Pressure related coefficients */
-	ret = regmap_bulk_read(data->regmap, BME680_P1_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_P1_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_P1_LSB_REG\n");
 		return ret;
 	}
 	calib->par_p1 = le16_to_cpu(buf);
 
-	ret = regmap_bulk_read(data->regmap, BME680_P2_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_P2_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_P2_LSB_REG\n");
 		return ret;
@@ -157,14 +161,16 @@ static int bme680_read_calib(struct bme680_data *data,
 	}
 	calib->par_p3 = tmp;
 
-	ret = regmap_bulk_read(data->regmap, BME680_P4_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_P4_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_P4_LSB_REG\n");
 		return ret;
 	}
 	calib->par_p4 = le16_to_cpu(buf);
 
-	ret = regmap_bulk_read(data->regmap, BME680_P5_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_P5_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_P5_LSB_REG\n");
 		return ret;
@@ -185,14 +191,16 @@ static int bme680_read_calib(struct bme680_data *data,
 	}
 	calib->par_p7 = tmp;
 
-	ret = regmap_bulk_read(data->regmap, BME680_P8_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_P8_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_P8_LSB_REG\n");
 		return ret;
 	}
 	calib->par_p8 = le16_to_cpu(buf);
 
-	ret = regmap_bulk_read(data->regmap, BME680_P9_LSB_REG, (u8 *) &buf, 2);
+	ret = regmap_bulk_read(data->regmap, BME680_P9_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_P9_LSB_REG\n");
 		return ret;
@@ -276,8 +284,8 @@ static int bme680_read_calib(struct bme680_data *data,
 	}
 	calib->par_gh1 = tmp;
 
-	ret = regmap_bulk_read(data->regmap, BME680_GH2_LSB_REG, (u8 *) &buf,
-			       2);
+	ret = regmap_bulk_read(data->regmap, BME680_GH2_LSB_REG,
+			       &buf, sizeof(buf));
 	if (ret < 0) {
 		dev_err(dev, "failed to read BME680_GH2_LSB_REG\n");
 		return ret;
@@ -615,7 +623,7 @@ static int bme680_read_temp(struct bme680_data *data, int *val)
 		return ret;
 
 	ret = regmap_bulk_read(data->regmap, BME680_REG_TEMP_MSB,
-			       (u8 *) &tmp, 3);
+			       &tmp, 3);
 	if (ret < 0) {
 		dev_err(dev, "failed to read temperature\n");
 		return ret;
@@ -656,7 +664,7 @@ static int bme680_read_press(struct bme680_data *data,
 		return ret;
 
 	ret = regmap_bulk_read(data->regmap, BME680_REG_PRESS_MSB,
-			       (u8 *) &tmp, 3);
+			       &tmp, 3);
 	if (ret < 0) {
 		dev_err(dev, "failed to read pressure\n");
 		return ret;
@@ -689,7 +697,7 @@ static int bme680_read_humid(struct bme680_data *data,
 		return ret;
 
 	ret = regmap_bulk_read(data->regmap, BM6880_REG_HUMIDITY_MSB,
-			       (u8 *) &tmp, 2);
+			       &tmp, sizeof(tmp));
 	if (ret < 0) {
 		dev_err(dev, "failed to read humidity\n");
 		return ret;
@@ -754,7 +762,7 @@ static int bme680_read_gas(struct bme680_data *data,
 	}
 
 	ret = regmap_bulk_read(data->regmap, BME680_REG_GAS_MSB,
-			       (u8 *) &tmp, 2);
+			       &tmp, sizeof(tmp));
 	if (ret < 0) {
 		dev_err(dev, "failed to read gas resistance\n");
 		return ret;