1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/platform/x86/amd/hsmp/hwmon.c b/drivers/platform/x86/amd/hsmp/hwmon.c
new file mode 100644
index 000000000000..0cc9a742497f
--- /dev/null
+++ b/drivers/platform/x86/amd/hsmp/hwmon.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD HSMP hwmon support
+ * Copyright (c) 2025, AMD.
+ * All Rights Reserved.
+ *
+ * This file provides hwmon implementation for HSMP interface.
+ */
+
+#include <asm/amd/hsmp.h>
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include "hsmp.h"
+
+#define HSMP_HWMON_NAME		"amd_hsmp_hwmon"
+
+static int hsmp_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
+			    u32 attr, int channel, long val)
+{
+	u16 sock_ind = (uintptr_t)dev_get_drvdata(dev);
+	struct hsmp_message msg = {};
+
+	if (type != hwmon_power)
+		return -EOPNOTSUPP;
+
+	if (attr != hwmon_power_cap)
+		return -EOPNOTSUPP;
+
+	msg.num_args = 1;
+	msg.args[0] = val / MICROWATT_PER_MILLIWATT;
+	msg.msg_id = HSMP_SET_SOCKET_POWER_LIMIT;
+	msg.sock_ind = sock_ind;
+	return hsmp_send_message(&msg);
+}
+
+static int hsmp_hwmon_read(struct device *dev,
+			   enum hwmon_sensor_types type,
+			   u32 attr, int channel, long *val)
+{
+	u16 sock_ind = (uintptr_t)dev_get_drvdata(dev);
+	struct hsmp_message msg = {};
+	int ret;
+
+	if (type != hwmon_power)
+		return -EOPNOTSUPP;
+
+	msg.sock_ind = sock_ind;
+	msg.response_sz = 1;
+
+	switch (attr) {
+	case hwmon_power_input:
+		msg.msg_id = HSMP_GET_SOCKET_POWER;
+		break;
+	case hwmon_power_cap:
+		msg.msg_id = HSMP_GET_SOCKET_POWER_LIMIT;
+		break;
+	case hwmon_power_cap_max:
+		msg.msg_id = HSMP_GET_SOCKET_POWER_LIMIT_MAX;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	ret = hsmp_send_message(&msg);
+	if (!ret)
+		*val = msg.args[0] * MICROWATT_PER_MILLIWATT;
+
+	return ret;
+}
+
+static umode_t hsmp_hwmon_is_visble(const void *data,
+				    enum hwmon_sensor_types type,
+				    u32 attr, int channel)
+{
+	if (type != hwmon_power)
+		return 0;
+
+	switch (attr) {
+	case hwmon_power_input:
+		return 0444;
+	case hwmon_power_cap:
+		return 0644;
+	case hwmon_power_cap_max:
+		return 0444;
+	default:
+		return 0;
+	}
+}
+
+static const struct hwmon_ops hsmp_hwmon_ops = {
+	.read = hsmp_hwmon_read,
+	.is_visible = hsmp_hwmon_is_visble,
+	.write	= hsmp_hwmon_write,
+};
+
+static const struct hwmon_channel_info * const hsmp_info[] = {
+	HWMON_CHANNEL_INFO(power, HWMON_P_INPUT | HWMON_P_CAP | HWMON_P_CAP_MAX),
+	NULL
+};
+
+static const struct hwmon_chip_info hsmp_chip_info = {
+	.ops = &hsmp_hwmon_ops,
+	.info = hsmp_info,
+};
+
+int hsmp_create_sensor(struct device *dev, u16 sock_ind)
+{
+	struct device *hwmon_dev;
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, HSMP_HWMON_NAME,
+							 (void *)(uintptr_t)sock_ind,
+							 &hsmp_chip_info,
+							 NULL);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+EXPORT_SYMBOL_NS(hsmp_create_sensor, "AMD_HSMP");