blob: cd95b691d485ef218c4868bc2c89c64ce30df73d [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0+ */
/*
* A general-purpose cyclic execution infrastructure, to allow "small"
* (run-time wise) functions to be executed at a specified frequency.
* Things like LED blinking or watchdog triggering are examples for such
* tasks.
*
* Copyright (C) 2022 Stefan Roese <sr@denx.de>
*/
#ifndef __cyclic_h
#define __cyclic_h
#include <linux/list.h>
#include <asm/types.h>
/**
* struct cyclic_info - Information about cyclic execution function
*
* @func: Function to call periodically
* @name: Name of the cyclic function, e.g. shown in the commands
* @delay_ns: Delay is ns after which this function shall get executed
* @start_time_us: Start time in us, when this function started its execution
* @cpu_time_us: Total CPU time of this function
* @run_cnt: Counter of executions occurances
* @next_call: Next time in us, when the function shall be executed again
* @list: List node
* @already_warned: Flag that we've warned about exceeding CPU time usage
*
* When !CONFIG_CYCLIC, this struct is empty.
*/
struct cyclic_info {
#if defined(CONFIG_CYCLIC)
void (*func)(struct cyclic_info *c);
const char *name;
uint64_t delay_us;
uint64_t start_time_us;
uint64_t cpu_time_us;
uint64_t run_cnt;
uint64_t next_call;
struct hlist_node list;
bool already_warned;
#endif
};
/** Function type for cyclic functions */
typedef void (*cyclic_func_t)(struct cyclic_info *c);
#if CONFIG_IS_ENABLED(CYCLIC)
/**
* cyclic_register - Register a new cyclic function
*
* @cyclic: Cyclic info structure
* @func: Function to call periodically
* @delay_us: Delay is us after which this function shall get executed
* @name: Cyclic function name/id
*
* The function @func will be called with @cyclic as its
* argument. @cyclic will usually be embedded in some device-specific
* structure, which the callback can retrieve using container_of().
*/
void cyclic_register(struct cyclic_info *cyclic, cyclic_func_t func,
uint64_t delay_us, const char *name);
/**
* cyclic_unregister - Unregister a cyclic function
*
* @cyclic: Pointer to cyclic_struct of the function that shall be removed
*/
void cyclic_unregister(struct cyclic_info *cyclic);
/**
* cyclic_unregister_all() - Clean up cyclic functions
*
* This removes all cyclic functions
*/
int cyclic_unregister_all(void);
/**
* cyclic_get_list() - Get cyclic list pointer
*
* Return the cyclic list pointer
*
* @return: pointer to cyclic_list
*/
struct hlist_head *cyclic_get_list(void);
/**
* cyclic_run() - Interate over all registered cyclic functions
*
* Interate over all registered cyclic functions and if the it's function
* needs to be executed, then call into these registered functions.
*/
void cyclic_run(void);
/**
* schedule() - Schedule all potentially waiting tasks
*
* Basically a wrapper for cyclic_run(), pontentially enhanced by some
* other parts, that need to get handled periodically.
*/
void schedule(void);
#else
static inline void cyclic_register(struct cyclic_info *cyclic, cyclic_func_t func,
uint64_t delay_us, const char *name)
{
}
static inline void cyclic_unregister(struct cyclic_info *cyclic)
{
}
static inline void cyclic_run(void)
{
}
static inline void schedule(void)
{
}
static inline int cyclic_unregister_all(void)
{
return 0;
}
#endif /* CYCLIC */
#endif