@@ -83,6 +83,7 @@ obj-$(CONFIG_ACPI_TINY_POWER_BUTTON) += tiny-power-button.o
obj-$(CONFIG_ACPI_FAN) += fan.o
fan-objs := fan_core.o
fan-objs += fan_attr.o
+fan-objs += fan_hwmon.o
obj-$(CONFIG_ACPI_VIDEO) += video.o
obj-$(CONFIG_ACPI_TAD) += acpi_tad.o
@@ -56,4 +56,6 @@ struct acpi_fan {
int acpi_fan_get_fst(struct acpi_device *device, struct acpi_fan_fst *fst);
int acpi_fan_create_attributes(struct acpi_device *device);
void acpi_fan_delete_attributes(struct acpi_device *device);
+
+int devm_acpi_fan_create_hwmon(struct acpi_device *device);
#endif
@@ -7,6 +7,7 @@
* Copyright (C) 2022 Intel Corporation. All rights reserved.
*/
+#include <linux/kconfig.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
@@ -336,6 +337,12 @@ static int acpi_fan_probe(struct platform_device *pdev)
if (result)
return result;
+ if (IS_REACHABLE(CONFIG_HWMON)) {
+ result = devm_acpi_fan_create_hwmon(device);
+ if (result)
+ return result;
+ }
+
result = acpi_fan_create_attributes(device);
if (result)
return result;
new file mode 100644
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * fan_hwmon.c - hwmon interface for the ACPI Fan driver
+ *
+ * Copyright (C) 2024 Armin Wolf <W_Armin@gmx.de>
+ */
+
+#include <linux/acpi.h>
+#include <linux/hwmon.h>
+#include <linux/limits.h>
+
+#include "fan.h"
+
+static umode_t acpi_fan_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
+ int channel)
+{
+ return 0444;
+}
+
+static int acpi_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+ long *val)
+{
+ struct acpi_device *adev = dev_get_drvdata(dev);
+ struct acpi_fan_fst fst;
+ int ret;
+
+ switch (type) {
+ case hwmon_fan:
+ ret = acpi_fan_get_fst(adev, &fst);
+ if (ret < 0)
+ return ret;
+
+ switch (attr) {
+ case hwmon_fan_input:
+ if (fst.speed > LONG_MAX)
+ return -EOVERFLOW;
+
+ *val = fst.speed;
+ return 0;
+ case hwmon_fan_fault:
+ *val = (fst.speed == U32_MAX);
+ return 0;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static const struct hwmon_ops acpi_fan_ops = {
+ .is_visible = acpi_fan_is_visible,
+ .read = acpi_fan_read,
+};
+
+static const struct hwmon_channel_info * const acpi_fan_info[] = {
+ HWMON_CHANNEL_INFO(fan,
+ HWMON_F_INPUT | HWMON_F_FAULT),
+ NULL
+};
+
+static const struct hwmon_chip_info acpi_fan_chip_info = {
+ .ops = &acpi_fan_ops,
+ .info = acpi_fan_info,
+};
+
+int devm_acpi_fan_create_hwmon(struct acpi_device *device)
+{
+ struct device *hdev;
+
+ hdev = devm_hwmon_device_register_with_info(&device->dev, "acpi_fan", device,
+ &acpi_fan_chip_info, NULL);
+
+ return PTR_ERR_OR_ZERO(hdev);
+}
Currently, the driver does only supports a custom sysfs interface to allow userspace to read the fan speed. Add support for the standard hwmon interface so users can read the fan speed with standard tools like "sensors". Signed-off-by: Armin Wolf <W_Armin@gmx.de> --- drivers/acpi/Makefile | 1 + drivers/acpi/fan.h | 2 ++ drivers/acpi/fan_core.c | 7 ++++ drivers/acpi/fan_hwmon.c | 78 ++++++++++++++++++++++++++++++++++++++++ 4 files changed, 88 insertions(+) create mode 100644 drivers/acpi/fan_hwmon.c -- 2.39.2