Message-Id: <D87MG1SMP0WA.1EXT0WKP65DQR@gmail.com>
Date: Tue, 04 Mar 2025 11:27:39 -0500
From: "Kurt Borja" <kuurtb@...il.com>
To: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
Cc: "Armin Wolf" <W_Armin@....de>, <platform-driver-x86@...r.kernel.org>,
 "Hans de Goede" <hdegoede@...hat.com>, <Dell.Client.Kernel@...l.com>,
 "LKML" <linux-kernel@...r.kernel.org>, "Guenter Roeck" <linux@...ck-us.net>
Subject: Re: [PATCH v2 07/10] platform/x86: alienware-wmi-wmax: Add HWMON
 support

On Tue Mar 4, 2025 at 10:53 AM -05, Ilpo Järvinen wrote:
> On Tue, 25 Feb 2025, Kurt Borja wrote:
>
>> All models with the "AWCC" WMAX device support monitoring fan speed and
>> temperature sensors. Expose this feature through the HWMON interface.
>> 
>> Sensor readings are cached for 1 second before refreshing them to
>> mitigate the performance cost of calling WMI methods.
>> 
>> Cc: Guenter Roeck <linux@...ck-us.net>
>> Signed-off-by: Kurt Borja <kuurtb@...il.com>
>> ---
>>  drivers/platform/x86/dell/Kconfig             |   1 +
>>  .../platform/x86/dell/alienware-wmi-wmax.c    | 403 ++++++++++++++++++
>>  2 files changed, 404 insertions(+)
>> 
>> diff --git a/drivers/platform/x86/dell/Kconfig b/drivers/platform/x86/dell/Kconfig
>> index f8a0dffcaab7..85a57c01aaad 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 bbe87f91fcb6..818023a5b205 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 +42,10 @@
>>  /* Arbitrary limit based on supported models */
>>  #define AWCC_MAX_RES_COUNT			16
>>  
>> +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);
>>  MODULE_PARM_DESC(force_platform_profile, "Forces auto-detecting thermal profiles without checking if WMI thermal backend is available");
>> @@ -47,16 +55,19 @@ 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,
>>  };
>> @@ -154,9 +165,18 @@ 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,
>>  };
>>  
>> @@ -179,6 +199,12 @@ 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,
>> +	AWCC_TEMP_SENSOR_LAST
>> +};
>> +
>>  enum awcc_thermal_profile {
>>  	AWCC_PROFILE_USTT_BALANCED,
>>  	AWCC_PROFILE_USTT_BALANCED_PERFORMANCE,
>> @@ -215,6 +241,15 @@ struct wmax_u32_args {
>>  	u8 arg3;
>>  } __packed;
>>  
>> +struct awcc_fan_data {
>> +	unsigned long *related_temps;
>> +	unsigned long *auto_channels_temp;
>> +	u32 total_temps;
>> +	u32 min_rpm;
>> +	u32 max_rpm;
>> +	u8 id;
>> +};
>> +
>>  struct awcc_priv {
>>  	struct wmi_device *wdev;
>>  	union {
>> @@ -230,6 +265,11 @@ struct awcc_priv {
>>  
>>  	struct device *ppdev;
>>  	u8 supported_profiles[PLATFORM_PROFILE_LAST];
>> +
>> +	struct device *hwdev;
>> +	struct awcc_fan_data **fan_data;
>> +	unsigned int temp_sensors_size;
>> +	unsigned long *temp_sensors;
>>  };
>>  
>>  static const enum platform_profile_option awcc_mode_to_platform_profile[AWCC_PROFILE_LAST] = {
>> @@ -494,6 +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)
>>  {
>> @@ -564,6 +617,343 @@ 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);
>>  }
>>  
>> +/*
>> + * 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;
>> +
>> +	switch (type) {
>> +	case hwmon_temp:
>> +		if (channel < priv->temp_count)
>> +			return 0444;
>> +
>> +		break;
>
> IMO, these could be written as:
> 		return channel < priv->temp_count ? 0444 : 0;

Ack.

>
>> +	case hwmon_fan:
>> +		if (channel < priv->fan_count)
>> +			return 0444;
>> +
>> +		break;
>> +	case hwmon_pwm:
>> +		if (channel < priv->fan_count)
>> +			return 0444;
>> +
>> +		break;
>> +	default:
>> +		break;
>> +	}
>> +
>> +	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);
>> +	struct awcc_fan_data *fan;
>> +	u32 state;
>> +	int ret;
>> +	u8 temp;
>> +
>> +	switch (type) {
>> +	case hwmon_temp:
>> +		temp = find_nth_bit(priv->temp_sensors, U8_MAX, channel);
>> +		if (temp >= U8_MAX)
>
> It cannot be larger than as its type is u8??

Thanks, I forgot to change this! U8_MAX should be replaced with
priv->temp_sensors_size.

Thank you for reviewing this set! :)

-- 
 ~ Kurt

>
>> +			return -ENXIO;
>> +
>> +		switch (attr) {
>> +		case hwmon_temp_input:
>> +			ret = awcc_thermal_information(priv->wdev, AWCC_OP_GET_TEMPERATURE,
>> +						       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_thermal_information(priv->wdev, AWCC_OP_GET_FAN_RPM,
>> +						       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];
>> +
>> +		bitmap_copy(val, fan->auto_channels_temp, BITS_PER_LONG);
>> +		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);
>> +	struct awcc_fan_data *fan;
>> +	u8 temp;
>> +
>> +	switch (type) {
>> +	case hwmon_temp:
>> +		temp = find_nth_bit(priv->temp_sensors, U8_MAX, channel);
>> +		if (temp >= U8_MAX)
>> +			return -ENXIO;
>> +
>> +		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:
>> +		fan = priv->fan_data[channel];
>> +
>> +		switch (fan->total_temps) {
>> +		case 0:
>> +			*str = "Independent Fan";
>> +			break;
>> +		case 1:
>> +			temp = find_first_bit(fan->related_temps, U8_MAX);
>> +
>> +			switch (temp) {
>> +			case AWCC_TEMP_SENSOR_CPU:
>> +				*str = "Processor Fan";
>> +				break;
>> +			case AWCC_TEMP_SENSOR_GPU:
>> +				*str = "Video Fan";
>> +				break;
>> +			default:
>> +				*str = "Unknown Fan";
>> +				break;
>> +			}
>> +
>> +			break;
>> +		default:
>> +			*str = "Shared Fan";
>> +			break;
>> +		}
>> +
>> +		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 long temp_sensors[BITS_TO_LONGS(U8_MAX)];
>> +	unsigned int i, max_sensor_id = 0;
>> +	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;
>> +
>> +		id = FIELD_GET(AWCC_RESOURCE_ID_MASK, id);
>> +		if (id > max_sensor_id)
>> +			max_sensor_id = id;
>> +
>> +		ret = __test_and_set_bit(id, temp_sensors);
>> +		if (ret)
>> +			dev_warn(&wdev->dev, "Sensor ID at index %u is duplicated\n", i);
>> +	}
>> +
>> +	/*
>> +	 * We prefer to allocate the bitmap dynamically because usually temp IDs
>> +	 * are small (< 0x30) and only one UL is needed to store it, but there
>> +	 * may be unknown devices that break this rule
>> +	 */
>> +	priv->temp_sensors_size = max_sensor_id + 1;
>> +	priv->temp_sensors = devm_bitmap_zalloc(&wdev->dev, priv->temp_sensors_size,
>> +						GFP_KERNEL);
>> +	if (!priv->temp_sensors)
>> +		return -ENOMEM;
>> +
>> +	bitmap_copy(priv->temp_sensors, temp_sensors, priv->temp_sensors_size);
>> +
>> +	return 0;
>> +}
>> +
>> +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, total_fan_temps, temp_id;
>> +	unsigned long gather[BITS_TO_LONGS(U8_MAX)];
>> +	struct awcc_fan_data *fan_data;
>> +	unsigned int i, j;
>> +	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_data->related_temps = devm_bitmap_zalloc(&wdev->dev,
>> +							     priv->temp_sensors_size,
>> +							     GFP_KERNEL);
>> +		if (!priv->temp_sensors)
>> +			return -ENOMEM;
>> +
>> +		fan_data->auto_channels_temp = devm_bitmap_zalloc(&wdev->dev,
>> +								  priv->temp_count,
>> +								  GFP_KERNEL);
>> +		if (!priv->temp_sensors)
>> +			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, &total_fan_temps);
>> +		if (ret)
>> +			return ret;
>> +
>> +		for (j = 0; j < total_fan_temps; 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);
>> +			if (temp_id < priv->temp_sensors_size)
>> +				__set_bit(temp_id, fan_data->related_temps);
>> +		}
>> +
>> +		fan_data->id = id;
>> +		fan_data->min_rpm = min_rpm;
>> +		fan_data->max_rpm = max_rpm;
>> +		fan_data->total_temps = total_fan_temps;
>> +		bitmap_gather(gather, fan_data->related_temps, priv->temp_sensors,
>> +			      priv->temp_sensors_size);
>> +		bitmap_copy(fan_data->auto_channels_temp, gather, priv->temp_count);
>> +		priv->fan_data[i] = fan_data;
>> +	}
>> +
>> +	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
>> @@ -735,6 +1125,12 @@ 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)
>> @@ -815,6 +1211,13 @@ 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;
>> 

Powered by blists - more mailing lists