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

Armin Wolf
2025-03-11T18:55:31Z

Am 08.03.25 um 21:23 schrieb Kurt Borja:

> 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);

All of those strings are static, please drop the usage of devm_kstrdup() here.

With those issues being addressed:
Reviewed-by: Armin Wolf <W_Armin@gmx.de>

> + 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);

Please check that the bitmap can fit into the long variable before using bitmap_copy().

> + 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;
>