From 447c4e8338dbfad517769d26b53d633b88d51184 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Thu, 30 Oct 2025 20:26:28 +0200 Subject: PM / devfreq: Move governor.h to a public header location Some device drivers (and out-of-tree modules) might want to define device-specific device governors. Rather than restricting all of them to be a part of drivers/devfreq/ (which is not possible for out-of-tree drivers anyway) move governor.h to include/linux/devfreq-governor.h and update all drivers to use it. The devfreq_cpu_data is only used internally, by the passive governor, so it is moved to the driver source rather than being a part of the public interface. Reported-by: Robie Basak Acked-by: Jon Hunter Signed-off-by: Dmitry Baryshkov Reviewed-by: Bjorn Andersson Acked-by: MyungJoo Ham Signed-off-by: Chanwoo Choi Link: https://patchwork.kernel.org/project/linux-pm/patch/20251030-governor-public-v2-1-432a11a9975a@oss.qualcomm.com/ --- include/linux/devfreq-governor.h | 102 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100644 include/linux/devfreq-governor.h (limited to 'include/linux') diff --git a/include/linux/devfreq-governor.h b/include/linux/devfreq-governor.h new file mode 100644 index 000000000000..dfdd0160a29f --- /dev/null +++ b/include/linux/devfreq-governor.h @@ -0,0 +1,102 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * governor.h - internal header for devfreq governors. + * + * Copyright (C) 2011 Samsung Electronics + * MyungJoo Ham + * + * This header is for devfreq governors + */ + +#ifndef __LINUX_DEVFREQ_DEVFREQ_H__ +#define __LINUX_DEVFREQ_DEVFREQ_H__ + +#include + +#define DEVFREQ_NAME_LEN 16 + +#define to_devfreq(DEV) container_of((DEV), struct devfreq, dev) + +/* Devfreq events */ +#define DEVFREQ_GOV_START 0x1 +#define DEVFREQ_GOV_STOP 0x2 +#define DEVFREQ_GOV_UPDATE_INTERVAL 0x3 +#define DEVFREQ_GOV_SUSPEND 0x4 +#define DEVFREQ_GOV_RESUME 0x5 + +#define DEVFREQ_MIN_FREQ 0 +#define DEVFREQ_MAX_FREQ ULONG_MAX + +/* + * Definition of the governor feature flags + * - DEVFREQ_GOV_FLAG_IMMUTABLE + * : This governor is never changeable to other governors. + * - DEVFREQ_GOV_FLAG_IRQ_DRIVEN + * : The devfreq won't schedule the work for this governor. + */ +#define DEVFREQ_GOV_FLAG_IMMUTABLE BIT(0) +#define DEVFREQ_GOV_FLAG_IRQ_DRIVEN BIT(1) + +/* + * Definition of governor attribute flags except for common sysfs attributes + * - DEVFREQ_GOV_ATTR_POLLING_INTERVAL + * : Indicate polling_interval sysfs attribute + * - DEVFREQ_GOV_ATTR_TIMER + * : Indicate timer sysfs attribute + */ +#define DEVFREQ_GOV_ATTR_POLLING_INTERVAL BIT(0) +#define DEVFREQ_GOV_ATTR_TIMER BIT(1) + +/** + * struct devfreq_governor - Devfreq policy governor + * @node: list node - contains registered devfreq governors + * @name: Governor's name + * @attrs: Governor's sysfs attribute flags + * @flags: Governor's feature flags + * @get_target_freq: Returns desired operating frequency for the device. + * Basically, get_target_freq will run + * devfreq_dev_profile.get_dev_status() to get the + * status of the device (load = busy_time / total_time). + * @event_handler: Callback for devfreq core framework to notify events + * to governors. Events include per device governor + * init and exit, opp changes out of devfreq, suspend + * and resume of per device devfreq during device idle. + * + * Note that the callbacks are called with devfreq->lock locked by devfreq. + */ +struct devfreq_governor { + struct list_head node; + + const char name[DEVFREQ_NAME_LEN]; + const u64 attrs; + const u64 flags; + int (*get_target_freq)(struct devfreq *this, unsigned long *freq); + int (*event_handler)(struct devfreq *devfreq, + unsigned int event, void *data); +}; + +void devfreq_monitor_start(struct devfreq *devfreq); +void devfreq_monitor_stop(struct devfreq *devfreq); +void devfreq_monitor_suspend(struct devfreq *devfreq); +void devfreq_monitor_resume(struct devfreq *devfreq); +void devfreq_update_interval(struct devfreq *devfreq, unsigned int *delay); + +int devfreq_add_governor(struct devfreq_governor *governor); +int devfreq_remove_governor(struct devfreq_governor *governor); + +int devm_devfreq_add_governor(struct device *dev, + struct devfreq_governor *governor); + +int devfreq_update_status(struct devfreq *devfreq, unsigned long freq); +int devfreq_update_target(struct devfreq *devfreq, unsigned long freq); +void devfreq_get_freq_range(struct devfreq *devfreq, unsigned long *min_freq, + unsigned long *max_freq); + +static inline int devfreq_update_stats(struct devfreq *df) +{ + if (!df->profile->get_dev_status) + return -EINVAL; + + return df->profile->get_dev_status(df->dev.parent, &df->last_status); +} +#endif /* __LINUX_DEVFREQ_DEVFREQ_H__ */ -- cgit v1.2.3