1 files changed, 117 insertions, 92 deletions

diff --git a/drivers/hwmon/iio_hwmon.c b/drivers/hwmon/iio_hwmon.c
index 708081b68c6f..e376d4cde5ad 100644
--- a/drivers/hwmon/iio_hwmon.c
+++ b/drivers/hwmon/iio_hwmon.c
@@ -1,19 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /* Hwmon client for industrial I/O devices
  *
  * Copyright (c) 2011 Jonathan Cameron
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
  */
 
 #include <linux/kernel.h>
 #include <linux/slab.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
+
 #include <linux/hwmon.h>
-#include <linux/of.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/iio/consumer.h>
 #include <linux/iio/types.h>
@@ -22,18 +21,29 @@
  * struct iio_hwmon_state - device instance state
  * @channels:		filled with array of channels from iio
  * @num_channels:	number of channels in channels (saves counting twice)
- * @hwmon_dev:		associated hwmon device
- * @attr_group:	the group of attributes
+ * @attr_group:		the group of attributes
+ * @groups:		null terminated array of attribute groups
  * @attrs:		null terminated array of attribute pointers.
  */
 struct iio_hwmon_state {
 	struct iio_channel *channels;
 	int num_channels;
-	struct device *hwmon_dev;
 	struct attribute_group attr_group;
+	const struct attribute_group *groups[2];
 	struct attribute **attrs;
 };
 
+static ssize_t iio_hwmon_read_label(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
+	struct iio_hwmon_state *state = dev_get_drvdata(dev);
+	struct iio_channel *chan = &state->channels[sattr->index];
+
+	return iio_read_channel_label(chan, buf);
+}
+
 /*
  * Assumes that IIO and hwmon operate in the same base units.
  * This is supposed to be true, but needs verification for
@@ -47,149 +57,164 @@ static ssize_t iio_hwmon_read_val(struct device *dev,
 	int ret;
 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
 	struct iio_hwmon_state *state = dev_get_drvdata(dev);
+	struct iio_channel *chan = &state->channels[sattr->index];
+	enum iio_chan_type type;
 
-	ret = iio_read_channel_processed(&state->channels[sattr->index],
-					&result);
+	ret = iio_get_channel_type(chan, &type);
 	if (ret < 0)
 		return ret;
 
-	return sprintf(buf, "%d\n", result);
-}
-
-static ssize_t show_name(struct device *dev, struct device_attribute *attr,
-			 char *buf)
-{
-	const char *name = "iio_hwmon";
-
-	if (dev->of_node && dev->of_node->name)
-		name = dev->of_node->name;
+	if (type == IIO_POWER)
+		/* mili-Watts to micro-Watts conversion */
+		ret = iio_read_channel_processed_scale(chan, &result, 1000);
+	else
+		ret = iio_read_channel_processed(chan, &result);
+	if (ret < 0)
+		return ret;
 
-	return sprintf(buf, "%s\n", name);
+	return sprintf(buf, "%d\n", result);
 }
 
-static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
-
 static int iio_hwmon_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct iio_hwmon_state *st;
 	struct sensor_device_attribute *a;
-	int ret, i;
-	int in_i = 1, temp_i = 1, curr_i = 1;
+	int ret, i, attr = 0;
+	int in_i = 1, temp_i = 1, curr_i = 1, humidity_i = 1, power_i = 1;
 	enum iio_chan_type type;
 	struct iio_channel *channels;
-
-	channels = iio_channel_get_all(dev);
-	if (IS_ERR(channels))
-		return PTR_ERR(channels);
+	struct device *hwmon_dev;
+	char *sname;
+	void *buf;
+
+	channels = devm_iio_channel_get_all(dev);
+	if (IS_ERR(channels)) {
+		ret = PTR_ERR(channels);
+		if (ret == -ENODEV)
+			ret = -EPROBE_DEFER;
+		return dev_err_probe(dev, ret,
+				     "Failed to get channels\n");
+	}
 
 	st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
-	if (st == NULL) {
-		ret = -ENOMEM;
-		goto error_release_channels;
-	}
+	buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
+	if (!st || !buf)
+		return -ENOMEM;
 
 	st->channels = channels;
 
-	/* count how many attributes we have */
+	/* count how many channels we have */
 	while (st->channels[st->num_channels].indio_dev)
 		st->num_channels++;
 
-	st->attrs = devm_kzalloc(dev,
-				 sizeof(*st->attrs) * (st->num_channels + 2),
+	st->attrs = devm_kcalloc(dev,
+				 2 * st->num_channels + 1, sizeof(*st->attrs),
 				 GFP_KERNEL);
-	if (st->attrs == NULL) {
-		ret = -ENOMEM;
-		goto error_release_channels;
-	}
+	if (st->attrs == NULL)
+		return -ENOMEM;
 
 	for (i = 0; i < st->num_channels; i++) {
+		const char *prefix;
+		int n;
+
 		a = devm_kzalloc(dev, sizeof(*a), GFP_KERNEL);
-		if (a == NULL) {
-			ret = -ENOMEM;
-			goto error_release_channels;
-		}
+		if (a == NULL)
+			return -ENOMEM;
 
 		sysfs_attr_init(&a->dev_attr.attr);
 		ret = iio_get_channel_type(&st->channels[i], &type);
 		if (ret < 0)
-			goto error_release_channels;
+			return ret;
 
 		switch (type) {
 		case IIO_VOLTAGE:
-			a->dev_attr.attr.name = kasprintf(GFP_KERNEL,
-							  "in%d_input",
-							  in_i++);
+			n = in_i++;
+			prefix = "in";
 			break;
 		case IIO_TEMP:
-			a->dev_attr.attr.name = kasprintf(GFP_KERNEL,
-							  "temp%d_input",
-							  temp_i++);
+			n = temp_i++;
+			prefix = "temp";
 			break;
 		case IIO_CURRENT:
-			a->dev_attr.attr.name = kasprintf(GFP_KERNEL,
-							  "curr%d_input",
-							  curr_i++);
+			n = curr_i++;
+			prefix = "curr";
+			break;
+		case IIO_POWER:
+			n = power_i++;
+			prefix = "power";
+			break;
+		case IIO_HUMIDITYRELATIVE:
+			n = humidity_i++;
+			prefix = "humidity";
 			break;
 		default:
-			ret = -EINVAL;
-			goto error_release_channels;
-		}
-		if (a->dev_attr.attr.name == NULL) {
-			ret = -ENOMEM;
-			goto error_release_channels;
+			return -EINVAL;
 		}
+
+		a->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
+						       "%s%d_input",
+						       prefix, n);
+		if (a->dev_attr.attr.name == NULL)
+			return -ENOMEM;
+
 		a->dev_attr.show = iio_hwmon_read_val;
-		a->dev_attr.attr.mode = S_IRUGO;
+		a->dev_attr.attr.mode = 0444;
 		a->index = i;
-		st->attrs[i] = &a->dev_attr.attr;
-	}
-	st->attrs[st->num_channels] = &dev_attr_name.attr;
-	st->attr_group.attrs = st->attrs;
-	platform_set_drvdata(pdev, st);
-	ret = sysfs_create_group(&dev->kobj, &st->attr_group);
-	if (ret < 0)
-		goto error_release_channels;
+		st->attrs[attr++] = &a->dev_attr.attr;
 
-	st->hwmon_dev = hwmon_device_register(dev);
-	if (IS_ERR(st->hwmon_dev)) {
-		ret = PTR_ERR(st->hwmon_dev);
-		goto error_remove_group;
-	}
-	return 0;
+		/* Let's see if we have a label... */
+		if (iio_read_channel_label(&st->channels[i], buf) < 0)
+			continue;
 
-error_remove_group:
-	sysfs_remove_group(&dev->kobj, &st->attr_group);
-error_release_channels:
-	iio_channel_release_all(channels);
-	return ret;
-}
+		a = devm_kzalloc(dev, sizeof(*a), GFP_KERNEL);
+		if (a == NULL)
+			return -ENOMEM;
 
-static int iio_hwmon_remove(struct platform_device *pdev)
-{
-	struct iio_hwmon_state *st = platform_get_drvdata(pdev);
+		sysfs_attr_init(&a->dev_attr.attr);
+		a->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
+						       "%s%d_label",
+						       prefix, n);
+		if (!a->dev_attr.attr.name)
+			return -ENOMEM;
+
+		a->dev_attr.show = iio_hwmon_read_label;
+		a->dev_attr.attr.mode = 0444;
+		a->index = i;
+		st->attrs[attr++] = &a->dev_attr.attr;
+	}
+
+	devm_free_pages(dev, (unsigned long)buf);
 
-	hwmon_device_unregister(st->hwmon_dev);
-	sysfs_remove_group(&pdev->dev.kobj, &st->attr_group);
-	iio_channel_release_all(st->channels);
+	st->attr_group.attrs = st->attrs;
+	st->groups[0] = &st->attr_group;
+
+	if (dev_fwnode(dev)) {
+		sname = devm_kasprintf(dev, GFP_KERNEL, "%pfwP", dev_fwnode(dev));
+		if (!sname)
+			return -ENOMEM;
+		strreplace(sname, '-', '_');
+	} else {
+		sname = "iio_hwmon";
+	}
 
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, sname, st,
+							   st->groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
-static struct of_device_id iio_hwmon_of_match[] = {
+static const struct of_device_id iio_hwmon_of_match[] = {
 	{ .compatible = "iio-hwmon", },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, iio_hwmon_of_match);
 
-static struct platform_driver __refdata iio_hwmon_driver = {
+static struct platform_driver iio_hwmon_driver = {
 	.driver = {
 		.name = "iio_hwmon",
-		.owner = THIS_MODULE,
 		.of_match_table = iio_hwmon_of_match,
 	},
 	.probe = iio_hwmon_probe,
-	.remove = iio_hwmon_remove,
 };
 
 module_platform_driver(iio_hwmon_driver);