Commit afa7c56e authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Guenter Roeck
Browse files

hwmon: (cros_ec) Add support for temperature thresholds 



Implement reading temperature thresholds through
EC_CMD_THERMAL_GET_THRESHOLD/EC_CMD_THERMAL_SET_THRESHOLD.

Thresholds are mapped as follows between the EC and hwmon:

hwmon_temp_max       - EC_TEMP_THRESH_WARN
hwmon_temp_crit      - EC_TEMP_THRESH_HIGH
hwmon_temp_emergency - EC_TEMP_THRESH_HALT

Signed-off-by: default avatarThomas Weißschuh <linux@weissschuh.net>
Reviewed-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20260118-cros_ec-hwmon-pwm-v2-4-77eb1709b031@weissschuh.net


[groeck: Rearrange code to no longer use unreachable() since that causes
 a hiccup with some versions of gcc and objtool]
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 11c5802d

Documentation/hwmon/cros_ec_hwmon.rst

+3 −0
Original line number Diff line number Diff line
@@ -35,6 +35,9 @@ Fan target speed 
Temperature readings

    Always supported.



Temperature thresholds

    If supported by the EC.



PWM fan control

    If the EC also supports setting fan PWM values and fan mode.

drivers/hwmon/cros_ec_hwmon.c

+54 −3
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ struct cros_ec_hwmon_priv { 
	const char *temp_sensor_names[EC_TEMP_SENSOR_ENTRIES + EC_TEMP_SENSOR_B_ENTRIES];

	u8 usable_fans;

	bool fan_control_supported;

	bool temp_threshold_supported;

	u8 manual_fans; /* bits to indicate whether the fan is set to manual */

	u8 manual_fan_pwm[EC_FAN_SPEED_ENTRIES];

};
@@ -116,6 +117,23 @@ static int cros_ec_hwmon_read_temp(struct cros_ec_device *cros_ec, u8 index, u8 
	return 0;

}



static int cros_ec_hwmon_read_temp_threshold(struct cros_ec_device *cros_ec, u8 index,

					     enum ec_temp_thresholds threshold, u32 *temp)

{

	struct ec_params_thermal_get_threshold_v1 req = {};

	struct ec_thermal_config resp;

	int ret;



	req.sensor_num = index;

	ret = cros_ec_cmd(cros_ec, 1, EC_CMD_THERMAL_GET_THRESHOLD,

			  &req, sizeof(req), &resp, sizeof(resp));

	if (ret < 0)

		return ret;



	*temp = resp.temp_host[threshold];

	return 0;

}



static bool cros_ec_hwmon_is_error_fan(u16 speed)

{

	return speed == EC_FAN_SPEED_NOT_PRESENT || speed == EC_FAN_SPEED_STALLED;
@@ -134,12 +152,29 @@ static long cros_ec_hwmon_temp_to_millicelsius(u8 temp) 
	return kelvin_to_millicelsius((((long)temp) + EC_TEMP_SENSOR_OFFSET));

}



static bool cros_ec_hwmon_attr_is_temp_threshold(u32 attr)

{

	return attr == hwmon_temp_max ||

	       attr == hwmon_temp_crit ||

	       attr == hwmon_temp_emergency;

}



static enum ec_temp_thresholds cros_ec_hwmon_attr_to_thres(u32 attr)

{

	if (attr == hwmon_temp_max)

		return EC_TEMP_THRESH_WARN;

	else if (attr == hwmon_temp_crit)

		return EC_TEMP_THRESH_HIGH;

	return EC_TEMP_THRESH_HALT;	/* attr == hwmon_temp_emergency */

}



static int cros_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type,

			      u32 attr, int channel, long *val)

{

	struct cros_ec_hwmon_priv *priv = dev_get_drvdata(dev);

	int ret = -EOPNOTSUPP;

	u8 control_method;

	u32 threshold;

	u8 pwm_value;

	u16 speed;

	u8 temp;
@@ -187,6 +222,13 @@ static int cros_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type, 
			ret = cros_ec_hwmon_read_temp(priv->cros_ec, channel, &temp);

			if (ret == 0)

				*val = cros_ec_hwmon_is_error_temp(temp);



		} else if (cros_ec_hwmon_attr_is_temp_threshold(attr)) {

			ret = cros_ec_hwmon_read_temp_threshold(priv->cros_ec, channel,

								cros_ec_hwmon_attr_to_thres(attr),

								&threshold);

			if (ret == 0)

				*val = kelvin_to_millicelsius(threshold);

		}

	}
@@ -291,9 +333,15 @@ static umode_t cros_ec_hwmon_is_visible(const void *data, enum hwmon_sensor_type 
		if (priv->fan_control_supported && priv->usable_fans & BIT(channel))

			return 0644;

	} else if (type == hwmon_temp) {

		if (priv->temp_sensor_names[channel])

		if (priv->temp_sensor_names[channel]) {

			if (cros_ec_hwmon_attr_is_temp_threshold(attr)) {

				if (priv->temp_threshold_supported)

					return 0444;

			} else {

				return 0444;

			}

		}

	}



	return 0;

}
@@ -310,7 +358,8 @@ static const struct hwmon_channel_info * const cros_ec_hwmon_info[] = { 
			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,

			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,

			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),

#define CROS_EC_HWMON_TEMP_PARAMS (HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_LABEL)

#define CROS_EC_HWMON_TEMP_PARAMS (HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_LABEL | \

				   HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_EMERGENCY)

	HWMON_CHANNEL_INFO(temp,

			   CROS_EC_HWMON_TEMP_PARAMS,

			   CROS_EC_HWMON_TEMP_PARAMS,
@@ -520,6 +569,8 @@ static int cros_ec_hwmon_probe(struct platform_device *pdev) 
	cros_ec_hwmon_probe_temp_sensors(dev, priv, thermal_version);

	cros_ec_hwmon_probe_fans(priv);

	priv->fan_control_supported = cros_ec_hwmon_probe_fan_control_supported(priv->cros_ec);

	priv->temp_threshold_supported = is_cros_ec_cmd_available(priv->cros_ec,

								  EC_CMD_THERMAL_GET_THRESHOLD, 1);

	cros_ec_hwmon_register_fan_cooling_devices(dev, priv);



	hwmon_dev = devm_hwmon_device_register_with_info(dev, "cros_ec", priv,