1 files changed, 25 insertions, 51 deletions

diff --git a/drivers/hwmon/ad7314.c b/drivers/hwmon/ad7314.c
index f4f9b219bf16..59424103f634 100644
--- a/drivers/hwmon/ad7314.c
+++ b/drivers/hwmon/ad7314.c
@@ -1,10 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * AD7314 digital temperature sensor driver for AD7314, ADT7301 and ADT7302
  *
  * Copyright 2010 Analog Devices Inc.
  *
- * Licensed under the GPL-2 or later.
- *
  * Conversion to hwmon from IIO done by Jonathan Cameron <jic23@cam.ac.uk>
  */
 #include <linux/device.h>
@@ -16,17 +15,20 @@
 #include <linux/err.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
+#include <linux/bitops.h>
 
 /*
  * AD7314 temperature masks
  */
 #define AD7314_TEMP_MASK		0x7FE0
 #define AD7314_TEMP_SHIFT		5
+#define AD7314_LEADING_ZEROS_MASK	BIT(15)
 
 /*
  * ADT7301 and ADT7302 temperature masks
  */
 #define ADT7301_TEMP_MASK		0x3FFF
+#define ADT7301_LEADING_ZEROS_MASK	(BIT(15) | BIT(14))
 
 enum ad7314_variant {
 	adt7301,
@@ -36,7 +38,6 @@ enum ad7314_variant {
 
 struct ad7314_data {
 	struct spi_device	*spi_dev;
-	struct device		*hwmon_dev;
 	u16 rx ____cacheline_aligned;
 };
 
@@ -53,9 +54,9 @@ static int ad7314_spi_read(struct ad7314_data *chip)
 	return be16_to_cpu(chip->rx);
 }
 
-static ssize_t ad7314_show_temperature(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
+static ssize_t ad7314_temperature_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
 {
 	struct ad7314_data *chip = dev_get_drvdata(dev);
 	s16 data;
@@ -66,19 +67,27 @@ static ssize_t ad7314_show_temperature(struct device *dev,
 		return ret;
 	switch (spi_get_device_id(chip->spi_dev)->driver_data) {
 	case ad7314:
+		if (ret & AD7314_LEADING_ZEROS_MASK) {
+			/* Invalid read-out, leading zero part is missing */
+			return -EIO;
+		}
 		data = (ret & AD7314_TEMP_MASK) >> AD7314_TEMP_SHIFT;
-		data = (data << 6) >> 6;
+		data = sign_extend32(data, 9);
 
 		return sprintf(buf, "%d\n", 250 * data);
 	case adt7301:
 	case adt7302:
+		if (ret & ADT7301_LEADING_ZEROS_MASK) {
+			/* Invalid read-out, leading zero part is missing */
+			return -EIO;
+		}
 		/*
 		 * Documented as a 13 bit twos complement register
 		 * with a sign bit - which is a 14 bit 2's complement
 		 * register.  1lsb - 31.25 milli degrees centigrade
 		 */
 		data = ret & ADT7301_TEMP_MASK;
-		data = (data << 2) >> 2;
+		data = sign_extend32(data, 13);
 
 		return sprintf(buf, "%d\n",
 			       DIV_ROUND_CLOSEST(data * 3125, 100));
@@ -87,62 +96,29 @@ static ssize_t ad7314_show_temperature(struct device *dev,
 	}
 }
 
-static ssize_t ad7314_show_name(struct device *dev,
-				struct device_attribute *devattr, char *buf)
-{
-	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
-}
+static SENSOR_DEVICE_ATTR_RO(temp1_input, ad7314_temperature, 0);
 
-static DEVICE_ATTR(name, S_IRUGO, ad7314_show_name, NULL);
-static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
-			  ad7314_show_temperature, NULL, 0);
-
-static struct attribute *ad7314_attributes[] = {
-	&dev_attr_name.attr,
+static struct attribute *ad7314_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
 	NULL,
 };
 
-static const struct attribute_group ad7314_group = {
-	.attrs = ad7314_attributes,
-};
+ATTRIBUTE_GROUPS(ad7314);
 
 static int ad7314_probe(struct spi_device *spi_dev)
 {
-	int ret;
 	struct ad7314_data *chip;
+	struct device *hwmon_dev;
 
 	chip = devm_kzalloc(&spi_dev->dev, sizeof(*chip), GFP_KERNEL);
 	if (chip == NULL)
 		return -ENOMEM;
 
-	spi_set_drvdata(spi_dev, chip);
-
-	ret = sysfs_create_group(&spi_dev->dev.kobj, &ad7314_group);
-	if (ret < 0)
-		return ret;
-
-	chip->hwmon_dev = hwmon_device_register(&spi_dev->dev);
-	if (IS_ERR(chip->hwmon_dev)) {
-		ret = PTR_ERR(chip->hwmon_dev);
-		goto error_remove_group;
-	}
 	chip->spi_dev = spi_dev;
-
-	return 0;
-error_remove_group:
-	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
-	return ret;
-}
-
-static int ad7314_remove(struct spi_device *spi_dev)
-{
-	struct ad7314_data *chip = spi_get_drvdata(spi_dev);
-
-	hwmon_device_unregister(chip->hwmon_dev);
-	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
-
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(&spi_dev->dev,
+							   spi_dev->modalias,
+							   chip, ad7314_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
 static const struct spi_device_id ad7314_id[] = {
@@ -156,10 +132,8 @@ MODULE_DEVICE_TABLE(spi, ad7314_id);
 static struct spi_driver ad7314_driver = {
 	.driver = {
 		.name = "ad7314",
-		.owner = THIS_MODULE,
 	},
 	.probe = ad7314_probe,
-	.remove = ad7314_remove,
 	.id_table = ad7314_id,
 };