Commit bd7a455a authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Guenter Roeck
Browse files

hwmon: (cros_ec) Add support for fan target speed 



Use EC_CMD_PWM_GET_FAN_TARGET_RPM to retrieve the target fan speed.
The EC only supports this for the first fan.

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-v2-2-77eb1709b031@weissschuh.net


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 18ccf486

Documentation/hwmon/cros_ec_hwmon.rst

+3 −0
Original line number Diff line number Diff line
@@ -29,6 +29,9 @@ Supported features 
Fan readings

    Always supported.



Fan target speed

    If supported by the EC.



Temperature readings

    Always supported.

drivers/hwmon/cros_ec_hwmon.c

+25 −1
Original line number Diff line number Diff line
@@ -86,6 +86,20 @@ static int cros_ec_hwmon_read_pwm_enable(struct cros_ec_device *cros_ec, u8 inde 
	return 0;

}



static int cros_ec_hwmon_read_fan_target(struct cros_ec_device *cros_ec, u16 *speed)

{

	struct ec_response_pwm_get_fan_rpm resp;

	int ret;



	ret = cros_ec_cmd(cros_ec, 0, EC_CMD_PWM_GET_FAN_TARGET_RPM,

			  NULL, 0, &resp, sizeof(resp));

	if (ret < 0)

		return ret;



	*speed = resp.rpm;

	return 0;

}



static int cros_ec_hwmon_read_temp(struct cros_ec_device *cros_ec, u8 index, u8 *temp)

{

	unsigned int offset;
@@ -143,6 +157,11 @@ static int cros_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type, 
			ret = cros_ec_hwmon_read_fan_speed(priv->cros_ec, channel, &speed);

			if (ret == 0)

				*val = cros_ec_hwmon_is_error_fan(speed);



		} else if (attr == hwmon_fan_target) {

			ret = cros_ec_hwmon_read_fan_target(priv->cros_ec, &speed);

			if (ret == 0)

				*val = speed;

		}

	} else if (type == hwmon_pwm) {

		if (attr == hwmon_pwm_enable) {
@@ -259,8 +278,13 @@ static umode_t cros_ec_hwmon_is_visible(const void *data, enum hwmon_sensor_type 
					u32 attr, int channel)

{

	const struct cros_ec_hwmon_priv *priv = data;

	u16 speed;



	if (type == hwmon_fan) {

		if (attr == hwmon_fan_target &&

		    cros_ec_hwmon_read_fan_target(priv->cros_ec, &speed) == -EOPNOTSUPP)

			return 0;



		if (priv->usable_fans & BIT(channel))

			return 0444;

	} else if (type == hwmon_pwm) {
@@ -277,7 +301,7 @@ static umode_t cros_ec_hwmon_is_visible(const void *data, enum hwmon_sensor_type 
static const struct hwmon_channel_info * const cros_ec_hwmon_info[] = {

	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),

	HWMON_CHANNEL_INFO(fan,

			   HWMON_F_INPUT | HWMON_F_FAULT,

			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_TARGET,

			   HWMON_F_INPUT | HWMON_F_FAULT,

			   HWMON_F_INPUT | HWMON_F_FAULT,

			   HWMON_F_INPUT | HWMON_F_FAULT),