[PATCH v4 07/12] platform/x86: alienware-wmi-wmax: Add HWMON support

Kurt Borja
2025-03-08T20:24:00Z

All models with the "AWCC" WMAX device support monitoring fan speed and
temperature sensors. Expose this feature through the HWMON interface.

Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: linux-hwmon@vger.kernel.org
Signed-off-by: Kurt Borja <kuurtb@gmail.com>
---
drivers/platform/x86/dell/Kconfig | 1 +
drivers/platform/x86/dell/alienware-wmi-wmax.c | 396 +++++++++++++++++++++++++
2 files changed, 397 insertions(+)

diff --git a/drivers/platform/x86/dell/Kconfig b/drivers/platform/x86/dell/Kconfig
index f8a0dffcaab7c3b423472c5b9093011334a698c8..85a57c01aaada5d899cd8252e77ed6043da5cbdf 100644
--- a/drivers/platform/x86/dell/Kconfig
+++ b/drivers/platform/x86/dell/Kconfig
@@ -43,6 +43,7 @@ config ALIENWARE_WMI_WMAX
bool "Alienware WMAX WMI device driver"
default y
depends on ALIENWARE_WMI
+ depends on HWMON
select ACPI_PLATFORM_PROFILE
help
Alienware WMI driver with AlienFX LED, HDMI, amplifier, deep sleep and
diff --git a/drivers/platform/x86/dell/alienware-wmi-wmax.c b/drivers/platform/x86/dell/alienware-wmi-wmax.c
index 3b37e4456482bc284b8e867c1c5b6255fc6c8ef2..f1f20db206d47f644e8cd58a6d169c850606e75b 100644
--- a/drivers/platform/x86/dell/alienware-wmi-wmax.c
+++ b/drivers/platform/x86/dell/alienware-wmi-wmax.c
@@ -9,10 +9,13 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/bitfield.h>
+#include <linux/bitmap.h>
#include <linux/bits.h>
#include <linux/dmi.h>
+#include <linux/hwmon.h>
#include <linux/moduleparam.h>
#include <linux/platform_profile.h>
+#include <linux/units.h>
#include <linux/wmi.h>
#include "alienware-wmi.h"

@@ -25,6 +28,7 @@
#define WMAX_METHOD_BRIGHTNESS 0x3
#define WMAX_METHOD_ZONE_CONTROL 0x4

+#define AWCC_METHOD_GET_FAN_SENSORS 0x13
#define AWCC_METHOD_THERMAL_INFORMATION 0x14
#define AWCC_METHOD_THERMAL_CONTROL 0x15
#define AWCC_METHOD_GAME_SHIFT_STATUS 0x25
@@ -38,6 +42,12 @@

/* Arbitrary limit based on supported models */
#define AWCC_MAX_RES_COUNT 16
+#define AWCC_ID_BITMAP_SIZE (U8_MAX + 1)
+#define AWCC_ID_BITMAP_LONGS BITS_TO_LONGS(AWCC_ID_BITMAP_SIZE)
+
+static bool force_hwmon;
+module_param_unsafe(force_hwmon, bool, 0);
+MODULE_PARM_DESC(force_hwmon, "Force probing for HWMON support without checking if the WMI backend is available");

static bool force_platform_profile;
module_param_unsafe(force_platform_profile, bool, 0);
@@ -48,16 +58,19 @@ module_param_unsafe(force_gmode, bool, 0);
MODULE_PARM_DESC(force_gmode, "Forces G-Mode when performance profile is selected");

struct awcc_quirks {
+ bool hwmon;
bool pprof;
bool gmode;
};

static struct awcc_quirks g_series_quirks = {
+ .hwmon = true,
.pprof = true,
.gmode = true,
};

static struct awcc_quirks generic_quirks = {
+ .hwmon = true,
.pprof = true,
.gmode = false,
};
@@ -155,9 +168,18 @@ static const struct dmi_system_id awcc_dmi_table[] __initconst = {
},
};

+enum AWCC_GET_FAN_SENSORS_OPERATIONS {
+ AWCC_OP_GET_TOTAL_FAN_TEMPS = 0x01,
+ AWCC_OP_GET_FAN_TEMP_ID = 0x02,
+};
+
enum AWCC_THERMAL_INFORMATION_OPERATIONS {
AWCC_OP_GET_SYSTEM_DESCRIPTION = 0x02,
AWCC_OP_GET_RESOURCE_ID = 0x03,
+ AWCC_OP_GET_TEMPERATURE = 0x04,
+ AWCC_OP_GET_FAN_RPM = 0x05,
+ AWCC_OP_GET_FAN_MIN_RPM = 0x08,
+ AWCC_OP_GET_FAN_MAX_RPM = 0x09,
AWCC_OP_GET_CURRENT_PROFILE = 0x0B,
};

@@ -180,6 +202,11 @@ enum AWCC_SPECIAL_THERMAL_CODES {
AWCC_SPECIAL_PROFILE_GMODE = 0xAB,
};

+enum AWCC_TEMP_SENSOR_TYPES {
+ AWCC_TEMP_SENSOR_CPU = 0x01,
+ AWCC_TEMP_SENSOR_GPU = 0x06,
+};
+
enum awcc_thermal_profile {
AWCC_PROFILE_USTT_BALANCED,
AWCC_PROFILE_USTT_BALANCED_PERFORMANCE,
@@ -216,6 +243,14 @@ struct wmax_u32_args {
u8 arg3;
};

+struct awcc_fan_data {
+ unsigned long auto_channels_temp;
+ const char *label;
+ u32 min_rpm;
+ u32 max_rpm;
+ u8 id;
+};
+
struct awcc_priv {
struct wmi_device *wdev;
union {
@@ -231,6 +266,10 @@ struct awcc_priv {

struct device *ppdev;
u8 supported_profiles[PLATFORM_PROFILE_LAST];
+
+ struct device *hwdev;
+ struct awcc_fan_data **fan_data;
+ unsigned long temp_sensors[AWCC_ID_BITMAP_LONGS];
};

static const enum platform_profile_option awcc_mode_to_platform_profile[AWCC_PROFILE_LAST] = {
@@ -495,6 +534,19 @@ static int __awcc_wmi_command(struct wmi_device *wdev, u32 method_id,
return 0;
}

+static inline int awcc_get_fan_sensors(struct wmi_device *wdev, u8 operation,
+ u8 fan_id, u8 index, u32 *out)
+{
+ struct wmax_u32_args args = {
+ .operation = operation,
+ .arg1 = fan_id,
+ .arg2 = index,
+ .arg3 = 0,
+ };
+
+ return __awcc_wmi_command(wdev, AWCC_METHOD_GET_FAN_SENSORS, &args, out);
+}
+
static inline int awcc_thermal_information(struct wmi_device *wdev, u8 operation,
u8 arg, u32 *out)
{
@@ -552,6 +604,30 @@ static inline int awcc_op_get_resource_id(struct wmi_device *wdev, u8 index, u32
return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION, &args, out);
}

+static inline int awcc_op_get_fan_rpm(struct wmi_device *wdev, u8 fan_id, u32 *out)
+{
+ struct wmax_u32_args args = {
+ .operation = AWCC_OP_GET_FAN_RPM,
+ .arg1 = fan_id,
+ .arg2 = 0,
+ .arg3 = 0,
+ };
+
+ return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION, &args, out);
+}
+
+static inline int awcc_op_get_temperature(struct wmi_device *wdev, u8 temp_id, u32 *out)
+{
+ struct wmax_u32_args args = {
+ .operation = AWCC_OP_GET_TEMPERATURE,
+ .arg1 = temp_id,
+ .arg2 = 0,
+ .arg3 = 0,
+ };
+
+ return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION, &args, out);
+}
+
static inline int awcc_op_get_current_profile(struct wmi_device *wdev, u32 *out)
{
struct wmax_u32_args args = {
@@ -577,6 +653,313 @@ static inline int awcc_op_activate_profile(struct wmi_device *wdev, u8 profile)
return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_CONTROL, &args, &out);
}

+/*
+ * HWMON
+ * - Provides temperature and fan speed monitoring as well as manual fan
+ * control
+ */
+static umode_t awcc_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ const struct awcc_priv *priv = drvdata;
+ unsigned int temp_count;
+
+ switch (type) {
+ case hwmon_temp:
+ temp_count = bitmap_weight(priv->temp_sensors, AWCC_ID_BITMAP_SIZE);
+
+ return channel < temp_count ? 0444 : 0;
+ case hwmon_fan:
+ return channel < priv->fan_count ? 0444 : 0;
+ case hwmon_pwm:
+ return channel < priv->fan_count ? 0444 : 0;
+ default:
+ return 0;
+ }
+}
+
+static int awcc_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct awcc_priv *priv = dev_get_drvdata(dev);
+ const struct awcc_fan_data *fan;
+ u32 state;
+ int ret;
+ u8 temp;
+
+ switch (type) {
+ case hwmon_temp:
+ temp = find_nth_bit(priv->temp_sensors, AWCC_ID_BITMAP_SIZE, channel);
+
+ switch (attr) {
+ case hwmon_temp_input:
+ ret = awcc_op_get_temperature(priv->wdev, temp, &state);
+ if (ret)
+ return ret;
+
+ *val = state * MILLIDEGREE_PER_DEGREE;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ break;
+ case hwmon_fan:
+ fan = priv->fan_data[channel];
+
+ switch (attr) {
+ case hwmon_fan_input:
+ ret = awcc_op_get_fan_rpm(priv->wdev, fan->id, &state);
+ if (ret)
+ return ret;
+
+ *val = state;
+ break;
+ case hwmon_fan_min:
+ *val = fan->min_rpm;
+ break;
+ case hwmon_fan_max:
+ *val = fan->max_rpm;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ break;
+ case hwmon_pwm:
+ fan = priv->fan_data[channel];
+
+ switch (attr) {
+ case hwmon_pwm_auto_channels_temp:
+ *val = fan->auto_channels_temp;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int awcc_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, const char **str)
+{
+ struct awcc_priv *priv = dev_get_drvdata(dev);
+ u8 temp;
+
+ switch (type) {
+ case hwmon_temp:
+ temp = find_nth_bit(priv->temp_sensors, AWCC_ID_BITMAP_SIZE, channel);
+
+ switch (temp) {
+ case AWCC_TEMP_SENSOR_CPU:
+ *str = "CPU";
+ break;
+ case AWCC_TEMP_SENSOR_GPU:
+ *str = "GPU";
+ break;
+ default:
+ *str = "Unknown";
+ break;
+ }
+
+ break;
+ case hwmon_fan:
+ *str = priv->fan_data[channel]->label;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static const struct hwmon_ops awcc_hwmon_ops = {
+ .is_visible = awcc_hwmon_is_visible,
+ .read = awcc_hwmon_read,
+ .read_string = awcc_hwmon_read_string,
+};
+
+static const struct hwmon_channel_info * const awcc_hwmon_info[] = {
+ HWMON_CHANNEL_INFO(temp,
+ HWMON_T_LABEL | HWMON_T_INPUT,
+ HWMON_T_LABEL | HWMON_T_INPUT,
+ HWMON_T_LABEL | HWMON_T_INPUT,
+ HWMON_T_LABEL | HWMON_T_INPUT,
+ HWMON_T_LABEL | HWMON_T_INPUT,
+ HWMON_T_LABEL | HWMON_T_INPUT
+ ),
+ HWMON_CHANNEL_INFO(fan,
+ HWMON_F_LABEL | HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX,
+ HWMON_F_LABEL | HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX,
+ HWMON_F_LABEL | HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX,
+ HWMON_F_LABEL | HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX,
+ HWMON_F_LABEL | HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX,
+ HWMON_F_LABEL | HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX
+ ),
+ HWMON_CHANNEL_INFO(pwm,
+ HWMON_PWM_AUTO_CHANNELS_TEMP,
+ HWMON_PWM_AUTO_CHANNELS_TEMP,
+ HWMON_PWM_AUTO_CHANNELS_TEMP,
+ HWMON_PWM_AUTO_CHANNELS_TEMP,
+ HWMON_PWM_AUTO_CHANNELS_TEMP,
+ HWMON_PWM_AUTO_CHANNELS_TEMP
+ ),
+ NULL
+};
+
+static const struct hwmon_chip_info awcc_hwmon_chip_info = {
+ .ops = &awcc_hwmon_ops,
+ .info = awcc_hwmon_info,
+};
+
+static int awcc_hwmon_temps_init(struct wmi_device *wdev)
+{
+ struct awcc_priv *priv = dev_get_drvdata(&wdev->dev);
+ unsigned int i;
+ int ret;
+ u32 id;
+
+ for (i = 0; i < priv->temp_count; i++) {
+ /*
+ * Temperature sensors IDs are listed after the fan IDs at
+ * offset `fan_count`
+ */
+ ret = awcc_op_get_resource_id(wdev, i + priv->fan_count, &id);
+ if (ret)
+ return ret;
+
+ __set_bit(FIELD_GET(AWCC_RESOURCE_ID_MASK, id), priv->temp_sensors);
+ }
+
+ return 0;
+}
+
+static char *awcc_alloc_fan_label(struct device *dev, u32 temp_count, u8 temp_id)
+{
+ char *label;
+
+ switch (temp_count) {
+ case 0:
+ label = devm_kstrdup(dev, "Independent Fan", GFP_KERNEL);
+ break;
+ case 1:
+ switch (temp_id) {
+ case AWCC_TEMP_SENSOR_CPU:
+ label = devm_kstrdup(dev, "Processor Fan", GFP_KERNEL);
+ break;
+ case AWCC_TEMP_SENSOR_GPU:
+ label = devm_kstrdup(dev, "Video Fan", GFP_KERNEL);
+ break;
+ default:
+ label = devm_kstrdup(dev, "Unknown Fan", GFP_KERNEL);
+ break;
+ }
+
+ break;
+ default:
+ label = devm_kstrdup(dev, "Shared Fan", GFP_KERNEL);
+ break;
+ }
+
+ return label;
+}
+
+static int awcc_hwmon_fans_init(struct wmi_device *wdev)
+{
+ struct awcc_priv *priv = dev_get_drvdata(&wdev->dev);
+ u32 id, min_rpm, max_rpm, temp_count, temp_id;
+ unsigned long fan_temps[AWCC_ID_BITMAP_LONGS];
+ unsigned long gather[AWCC_ID_BITMAP_LONGS];
+ struct awcc_fan_data *fan_data;
+ unsigned int i, j;
+ char *label;
+ int ret;
+
+ for (i = 0; i < priv->fan_count; i++) {
+ fan_data = devm_kzalloc(&wdev->dev, sizeof(*fan_data), GFP_KERNEL);
+ if (!fan_data)
+ return -ENOMEM;
+
+ /*
+ * Fan IDs are listed first at offset 0
+ */
+ ret = awcc_op_get_resource_id(wdev, i, &id);
+ if (ret)
+ return ret;
+ id = FIELD_GET(AWCC_RESOURCE_ID_MASK, id);
+
+ ret = awcc_thermal_information(wdev, AWCC_OP_GET_FAN_MIN_RPM, id,
+ &min_rpm);
+ if (ret)
+ return ret;
+
+ ret = awcc_thermal_information(wdev, AWCC_OP_GET_FAN_MAX_RPM, id,
+ &max_rpm);
+ if (ret)
+ return ret;
+
+ ret = awcc_get_fan_sensors(wdev, AWCC_OP_GET_TOTAL_FAN_TEMPS, id,
+ 0, &temp_count);
+ if (ret)
+ return ret;
+
+ for (j = 0; j < temp_count; j++) {
+ ret = awcc_get_fan_sensors(wdev, AWCC_OP_GET_FAN_TEMP_ID,
+ id, j, &temp_id);
+ if (ret)
+ break;
+
+ temp_id = FIELD_GET(AWCC_RESOURCE_ID_MASK, temp_id);
+ __set_bit(temp_id, fan_temps);
+ }
+
+ label = awcc_alloc_fan_label(&wdev->dev, temp_count, temp_id);
+ if (!label)
+ return -ENOMEM;
+
+ fan_data->id = id;
+ fan_data->min_rpm = min_rpm;
+ fan_data->max_rpm = max_rpm;
+ fan_data->label = label;
+ bitmap_gather(gather, fan_temps, priv->temp_sensors, AWCC_ID_BITMAP_SIZE);
+ bitmap_copy(&fan_data->auto_channels_temp, gather, priv->temp_count);
+ priv->fan_data[i] = fan_data;
+
+ bitmap_zero(fan_temps, AWCC_ID_BITMAP_SIZE);
+ }
+
+ return 0;
+}
+
+static int awcc_hwmon_init(struct wmi_device *wdev)
+{
+ struct awcc_priv *priv = dev_get_drvdata(&wdev->dev);
+ int ret;
+
+ priv->fan_data = devm_kcalloc(&wdev->dev, priv->fan_count,
+ sizeof(*priv->fan_data), GFP_KERNEL);
+ if (!priv->fan_data)
+ return -ENOMEM;
+
+ ret = awcc_hwmon_temps_init(wdev);
+ if (ret)
+ return ret;
+
+ ret = awcc_hwmon_fans_init(wdev);
+ if (ret)
+ return ret;
+
+ priv->hwdev = devm_hwmon_device_register_with_info(&wdev->dev, "alienware_wmi", priv,
+ &awcc_hwmon_chip_info, NULL);
+
+ return PTR_ERR_OR_ZERO(priv->hwdev);
+}
+
/*
* Thermal Profile control
* - Provides thermal profile control through the Platform Profile API
@@ -744,6 +1127,12 @@ static int alienware_awcc_setup(struct wmi_device *wdev)
priv->wdev = wdev;
dev_set_drvdata(&wdev->dev, priv);

+ if (awcc->hwmon) {
+ ret = awcc_hwmon_init(wdev);
+ if (ret)
+ return ret;
+ }
+
if (awcc->pprof) {
ret = awcc_platform_profile_init(wdev);
if (ret)
@@ -824,6 +1213,13 @@ int __init alienware_wmax_wmi_init(void)
if (id)
awcc = id->driver_data;

+ if (force_hwmon) {
+ if (!awcc)
+ awcc = &empty_quirks;
+
+ awcc->hwmon = true;
+ }
+
if (force_platform_profile) {
if (!awcc)
awcc = &empty_quirks;

--
2.48.1