diff options
Diffstat (limited to 'drivers/platform/x86/lenovo/wmi-events.c')
| -rw-r--r-- | drivers/platform/x86/lenovo/wmi-events.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/platform/x86/lenovo/wmi-events.c b/drivers/platform/x86/lenovo/wmi-events.c new file mode 100644 index 000000000000..0994cd7dd504 --- /dev/null +++ b/drivers/platform/x86/lenovo/wmi-events.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Lenovo WMI Events driver. Lenovo WMI interfaces provide various + * hardware triggered events that many drivers need to have propagated. + * This driver provides a uniform entrypoint for these events so that + * any driver that needs to respond to these events can subscribe to a + * notifier chain. + * + * Copyright (C) 2025 Derek J. Clark <derekjohn.clark@gmail.com> + */ + +#include <linux/acpi.h> +#include <linux/export.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/types.h> +#include <linux/wmi.h> + +#include "wmi-events.h" +#include "wmi-gamezone.h" + +#define THERMAL_MODE_EVENT_GUID "D320289E-8FEA-41E0-86F9-911D83151B5F" + +#define LWMI_EVENT_DEVICE(guid, type) \ + .guid_string = (guid), .context = &(enum lwmi_events_type) \ + { \ + type \ + } + +static BLOCKING_NOTIFIER_HEAD(events_chain_head); + +struct lwmi_events_priv { + struct wmi_device *wdev; + enum lwmi_events_type type; +}; + +/** + * lwmi_events_register_notifier() - Add a notifier to the notifier chain. + * @nb: The notifier_block struct to register + * + * Call blocking_notifier_chain_register to register the notifier block to the + * lenovo-wmi-events driver blocking notifier chain. + * + * Return: 0 on success, %-EEXIST on error. + */ +int lwmi_events_register_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&events_chain_head, nb); +} +EXPORT_SYMBOL_NS_GPL(lwmi_events_register_notifier, "LENOVO_WMI_EVENTS"); + +/** + * lwmi_events_unregister_notifier() - Remove a notifier from the notifier + * chain. + * @nb: The notifier_block struct to unregister + * + * Call blocking_notifier_chain_unregister to unregister the notifier block + * from the lenovo-wmi-events driver blocking notifier chain. + * + * Return: 0 on success, %-ENOENT on error. + */ +int lwmi_events_unregister_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&events_chain_head, nb); +} +EXPORT_SYMBOL_NS_GPL(lwmi_events_unregister_notifier, "LENOVO_WMI_EVENTS"); + +/** + * devm_lwmi_events_unregister_notifier() - Remove a notifier from the notifier + * chain. + * @data: Void pointer to the notifier_block struct to unregister. + * + * Call lwmi_events_unregister_notifier to unregister the notifier block from + * the lenovo-wmi-events driver blocking notifier chain. + * + * Return: 0 on success, %-ENOENT on error. + */ +static void devm_lwmi_events_unregister_notifier(void *data) +{ + struct notifier_block *nb = data; + + lwmi_events_unregister_notifier(nb); +} + +/** + * devm_lwmi_events_register_notifier() - Add a notifier to the notifier chain. + * @dev: The parent device of the notifier_block struct. + * @nb: The notifier_block struct to register + * + * Call lwmi_events_register_notifier to register the notifier block to the + * lenovo-wmi-events driver blocking notifier chain. Then add, as a device + * managed action, unregister_notifier to automatically unregister the + * notifier block upon its parent device removal. + * + * Return: 0 on success, or an error code. + */ +int devm_lwmi_events_register_notifier(struct device *dev, + struct notifier_block *nb) +{ + int ret; + + ret = lwmi_events_register_notifier(nb); + if (ret < 0) + return ret; + + return devm_add_action_or_reset(dev, devm_lwmi_events_unregister_notifier, nb); +} +EXPORT_SYMBOL_NS_GPL(devm_lwmi_events_register_notifier, "LENOVO_WMI_EVENTS"); + +/** + * lwmi_events_notify() - Call functions for the notifier call chain. + * @wdev: The parent WMI device of the driver. + * @obj: ACPI object passed by the registered WMI Event. + * + * Validate WMI event data and notify all registered drivers of the event and + * its output. + * + * Return: 0 on success, or an error code. + */ +static void lwmi_events_notify(struct wmi_device *wdev, union acpi_object *obj) +{ + struct lwmi_events_priv *priv = dev_get_drvdata(&wdev->dev); + int sel_prof; + int ret; + + switch (priv->type) { + case LWMI_EVENT_THERMAL_MODE: + if (obj->type != ACPI_TYPE_INTEGER) + return; + + sel_prof = obj->integer.value; + + switch (sel_prof) { + case LWMI_GZ_THERMAL_MODE_QUIET: + case LWMI_GZ_THERMAL_MODE_BALANCED: + case LWMI_GZ_THERMAL_MODE_PERFORMANCE: + case LWMI_GZ_THERMAL_MODE_EXTREME: + case LWMI_GZ_THERMAL_MODE_CUSTOM: + ret = blocking_notifier_call_chain(&events_chain_head, + LWMI_EVENT_THERMAL_MODE, + &sel_prof); + if (ret == NOTIFY_BAD) + dev_err(&wdev->dev, + "Failed to send notification to call chain for WMI Events\n"); + return; + default: + dev_err(&wdev->dev, "Got invalid thermal mode: %x", + sel_prof); + return; + } + break; + default: + return; + } +} + +static int lwmi_events_probe(struct wmi_device *wdev, const void *context) +{ + struct lwmi_events_priv *priv; + + if (!context) + return -EINVAL; + + priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->wdev = wdev; + priv->type = *(enum lwmi_events_type *)context; + dev_set_drvdata(&wdev->dev, priv); + + return 0; +} + +static const struct wmi_device_id lwmi_events_id_table[] = { + { LWMI_EVENT_DEVICE(THERMAL_MODE_EVENT_GUID, LWMI_EVENT_THERMAL_MODE) }, + {} +}; + +static struct wmi_driver lwmi_events_driver = { + .driver = { + .name = "lenovo_wmi_events", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, + .id_table = lwmi_events_id_table, + .probe = lwmi_events_probe, + .notify = lwmi_events_notify, + .no_singleton = true, +}; + +module_wmi_driver(lwmi_events_driver); + +MODULE_DEVICE_TABLE(wmi, lwmi_events_id_table); +MODULE_AUTHOR("Derek J. Clark <derekjohn.clark@gmail.com>"); +MODULE_DESCRIPTION("Lenovo WMI Events Driver"); +MODULE_LICENSE("GPL"); |