platform/x86: hp-wmi: implement fan keep-alive

The firmware on some HP laptops automatically reverts the fan speed
control to "Auto" mode after a 120 second timeout window.

To ensure that the user-selected fan profile (Max/Manual) persists,
implement a keep-alive mechanism that periodically refreshes the fan
mode trigger before the timeout occurs.

- Introduce a delayed workqueue to trigger the fan mode refresh every 90
  seconds, ensuring the system maintains the correct fan mode setting.
- Integrate the refresh mechanism into hp_wmi_apply_fan_settings() to
  start, update or cancel the keep-alive process based on the current
  fan mode.

This ensures that the driver stays in sync with the hardware.

Tested on: HP Omen 16-wf1xxx (board ID 8C78)

Signed-off-by: Krishna Chomal <krishna.chomal108@gmail.com>
Link: https://patch.msgid.link/20260113123738.222244-4-krishna.chomal108@gmail.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
index d04e53ae1803c48cf7656851cb82d9a8146d092e..45ab644ff10e07566e5848681327ab26730e79a0 100644 (file)
--- a/drivers/platform/x86/hp/hp-wmi.c
+++ b/drivers/platform/x86/hp/hp-wmi.c
@@ -34,6 +34,7 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/types.h>
+#include <linux/workqueue.h>
 
 MODULE_AUTHOR("Matthew Garrett <mjg59@srcf.ucam.org>");
 MODULE_DESCRIPTION("HP laptop WMI driver");
@@ -368,6 +369,7 @@ struct hp_wmi_hwmon_priv {
        u8 gpu_delta;
        u8 mode;
        u8 pwm;
+       struct delayed_work keep_alive_dwork;
 };
 
 struct victus_s_fan_table_header {
@@ -386,6 +388,12 @@ struct victus_s_fan_table {
        struct victus_s_fan_table_entry entries[];
 } __packed;
 
+/*
+ * 90s delay to prevent the firmware from resetting fan mode after fixed
+ * 120s timeout
+ */
+#define KEEP_ALIVE_DELAY_SECS     90
+
 static inline u8 rpm_to_pwm(u8 rpm, struct hp_wmi_hwmon_priv *priv)
 {
        return fixp_linear_interpolate(0, 0, priv->max_rpm, U8_MAX,
@@ -2093,6 +2101,7 @@ static int __init hp_wmi_bios_setup(struct platform_device *device)
 static void __exit hp_wmi_bios_remove(struct platform_device *device)
 {
        int i;
+       struct hp_wmi_hwmon_priv *priv;
 
        for (i = 0; i < rfkill2_count; i++) {
                rfkill_unregister(rfkill2[i].rfkill);
@@ -2111,6 +2120,10 @@ static void __exit hp_wmi_bios_remove(struct platform_device *device)
                rfkill_unregister(wwan_rfkill);
                rfkill_destroy(wwan_rfkill);
        }
+
+       priv = platform_get_drvdata(device);
+       if (priv)
+               cancel_delayed_work_sync(&priv->keep_alive_dwork);
 }
 
 static int hp_wmi_resume_handler(struct device *device)
@@ -2179,12 +2192,20 @@ static int hp_wmi_apply_fan_settings(struct hp_wmi_hwmon_priv *priv)
                if (is_victus_s_thermal_profile())
                        hp_wmi_get_fan_count_userdefine_trigger();
                ret = hp_wmi_fan_speed_max_set(1);
-               return ret;
+               if (ret < 0)
+                       return ret;
+               schedule_delayed_work(&priv->keep_alive_dwork,
+                                     secs_to_jiffies(KEEP_ALIVE_DELAY_SECS));
+               return 0;
        case PWM_MODE_MANUAL:
                if (!is_victus_s_thermal_profile())
                        return -EOPNOTSUPP;
                ret = hp_wmi_fan_speed_set(priv, pwm_to_rpm(priv->pwm, priv));
-               return ret;
+               if (ret < 0)
+                       return ret;
+               schedule_delayed_work(&priv->keep_alive_dwork,
+                                     secs_to_jiffies(KEEP_ALIVE_DELAY_SECS));
+               return 0;
        case PWM_MODE_AUTO:
                if (is_victus_s_thermal_profile()) {
                        hp_wmi_get_fan_count_userdefine_trigger();
@@ -2192,7 +2213,10 @@ static int hp_wmi_apply_fan_settings(struct hp_wmi_hwmon_priv *priv)
                } else {
                        ret = hp_wmi_fan_speed_max_set(0);
                }
-               return ret;
+               if (ret < 0)
+                       return ret;
+               cancel_delayed_work_sync(&priv->keep_alive_dwork);
+               return 0;
        default:
                /* shouldn't happen */
                return -EINVAL;
@@ -2336,6 +2360,20 @@ static const struct hwmon_chip_info chip_info = {
        .info = info,
 };
 
+static void hp_wmi_hwmon_keep_alive_handler(struct work_struct *work)
+{
+       struct delayed_work *dwork;
+       struct hp_wmi_hwmon_priv *priv;
+
+       dwork = to_delayed_work(work);
+       priv = container_of(dwork, struct hp_wmi_hwmon_priv, keep_alive_dwork);
+       /*
+        * Re-apply the current hwmon context settings.
+        * NOTE: hp_wmi_apply_fan_settings will handle the re-scheduling.
+        */
+       hp_wmi_apply_fan_settings(priv);
+}
+
 static int hp_wmi_setup_fan_settings(struct hp_wmi_hwmon_priv *priv)
 {
        u8 fan_data[128] = { 0 };
@@ -2393,6 +2431,8 @@ static int hp_wmi_hwmon_init(void)
                return PTR_ERR(hwmon);
        }
 
+       INIT_DELAYED_WORK(&priv->keep_alive_dwork, hp_wmi_hwmon_keep_alive_handler);
+       platform_set_drvdata(hp_wmi_platform_dev, priv);
        hp_wmi_apply_fan_settings(priv);
 
        return 0;