drivers/hwmon/vexpress-hwmon.c

Source file repositories/reference/linux-study-clean/drivers/hwmon/vexpress-hwmon.c

File Facts

System
Linux kernel
Corpus path
drivers/hwmon/vexpress-hwmon.c
Extension
.c
Size
6653 bytes
Lines
245
Domain
Driver Families
Bucket
drivers/hwmon
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct vexpress_hwmon_data {
	struct device *hwmon_dev;
	struct regmap *reg;
};

static ssize_t vexpress_hwmon_label_show(struct device *dev,
		struct device_attribute *dev_attr, char *buffer)
{
	const char *label = of_get_property(dev->of_node, "label", NULL);

	return sysfs_emit(buffer, "%s\n", label);
}

static ssize_t vexpress_hwmon_u32_show(struct device *dev,
		struct device_attribute *dev_attr, char *buffer)
{
	struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
	int err;
	u32 value;

	err = regmap_read(data->reg, 0, &value);
	if (err)
		return err;

	return sysfs_emit(buffer, "%u\n", value /
			  to_sensor_dev_attr(dev_attr)->index);
}

static ssize_t vexpress_hwmon_u64_show(struct device *dev,
		struct device_attribute *dev_attr, char *buffer)
{
	struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
	int err;
	u32 value_hi, value_lo;

	err = regmap_read(data->reg, 0, &value_lo);
	if (err)
		return err;

	err = regmap_read(data->reg, 1, &value_hi);
	if (err)
		return err;

	return sysfs_emit(buffer, "%llu\n",
			  div_u64(((u64)value_hi << 32) | value_lo,
				  to_sensor_dev_attr(dev_attr)->index));
}

static umode_t vexpress_hwmon_attr_is_visible(struct kobject *kobj,
		struct attribute *attr, int index)
{
	struct device *dev = kobj_to_dev(kobj);
	struct device_attribute *dev_attr = container_of(attr,
				struct device_attribute, attr);

	if (dev_attr->show == vexpress_hwmon_label_show &&
			!of_property_present(dev->of_node, "label"))
		return 0;

	return attr->mode;
}

struct vexpress_hwmon_type {
	const char *name;
	const struct attribute_group **attr_groups;
};

#if !defined(CONFIG_REGULATOR_VEXPRESS)
static DEVICE_ATTR(in1_label, 0444, vexpress_hwmon_label_show, NULL);
static SENSOR_DEVICE_ATTR_RO(in1_input, vexpress_hwmon_u32, 1000);
static struct attribute *vexpress_hwmon_attrs_volt[] = {
	&dev_attr_in1_label.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	NULL
};
static struct attribute_group vexpress_hwmon_group_volt = {
	.is_visible = vexpress_hwmon_attr_is_visible,
	.attrs = vexpress_hwmon_attrs_volt,
};
static struct vexpress_hwmon_type vexpress_hwmon_volt = {
	.name = "vexpress_volt",
	.attr_groups = (const struct attribute_group *[]) {
		&vexpress_hwmon_group_volt,
		NULL,
	},
};
#endif

static DEVICE_ATTR(curr1_label, 0444, vexpress_hwmon_label_show, NULL);
static SENSOR_DEVICE_ATTR_RO(curr1_input, vexpress_hwmon_u32, 1000);

Annotation

Implementation Notes