reset/reset.c

/******************************************************************************
 *
 * This file is provided under a dual license.  When you use or
 * distribute this software, you may choose to be licensed under
 * version 2 of the GNU General Public License ("GPLv2 License")
 * or BSD License.
 *
 * GPLv2 License
 *
 * Copyright(C) 2017 MediaTek Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See http://www.gnu.org/licenses/gpl-2.0.html for more details.
 *
 * BSD LICENSE
 *
 * Copyright(C) 2017 MediaTek Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name of the copyright holder nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *****************************************************************************/
/*! \file   reset.c
*   \brief  reset module
*
*    This file contains all implementations of reset module
*/


/*******************************************************************************
*                         C O M P I L E R   F L A G S
********************************************************************************
*/

/*******************************************************************************
*                    E X T E R N A L   R E F E R E N C E S
********************************************************************************
*/
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/kthread.h>
#include <linux/timer.h>
#include "precomp.h"
#include "reset.h"



/**********************************************************************
*                                 M A C R O S
***********************************************************************
*/
#ifndef MSEC_PER_SEC
#define MSEC_PER_SEC 1000
#endif

/**********************************************************************
*                              C O N S T A N T S
***********************************************************************
*/
MODULE_LICENSE("Dual BSD/GPL");

const char *eventName[RFSM_EVENT_MAX + 1] = {
	"RFSM_EVENT_TRIGGER_RESET",
	"RFSM_EVENT_TIMEOUT",
	"RFSM_EVENT_PROBE_START",
	"RFSM_EVENT_PROBE_FAIL",
	"RFSM_EVENT_PROBE_SUCCESS",
	"RFSM_EVENT_REMOVE",
	"RFSM_EVENT_L0_RESET_READY",
	"RFSM_EVENT_L0_RESET_GOING",
	"RFSM_EVENT_L0_RESET_DONE",
	"RFSM_EVENT_All"
};


/**********************************************************************
*                             D A T A   T Y P E S
***********************************************************************
*/
struct ResetInfo {
	wait_queue_head_t resetko_waitq;
	struct task_struct *resetko_thread;

	struct mutex moduleMutex;
	struct mutex eventMutex;
	struct list_head moduleList;
	struct list_head eventList;
};

struct ResetEvent {
	struct list_head node;
	enum ModuleType module;
	enum ResetFsmEvent event;
};


/**********************************************************************
*                  F U N C T I O N   D E C L A R A T I O N S
***********************************************************************
*/

/**********************************************************************
*                            P U B L I C   D A T A
***********************************************************************
*/
uint8_t fgIsResetTrigger = false;
uint8_t fgIsBtTriggered = false;
EXPORT_SYMBOL(fgIsResetTrigger);
EXPORT_SYMBOL(fgIsBtTriggered);

/**********************************************************************
*                           P R I V A T E   D A T A
***********************************************************************
*/
static struct ResetInfo resetInfo = {0};
static char moduleName[RESET_MODULE_TYPE_MAX][RFSM_NAME_MAX_LEN];
static bool fgL0ResetDone;
static bool fgExit;

/**********************************************************************
*                              F U N C T I O N S
**********************************************************************/
static struct FsmEntity *findResetFsm(enum ModuleType module)
{
	struct FsmEntity *fsm, *next_fsm;

	list_for_each_entry_safe(fsm, next_fsm, &resetInfo.moduleList, node) {
		if (fsm->eModuleType == module)
			return fsm;
	}

	return NULL;
}

static void removeResetFsm(enum ModuleType module)
{
	struct FsmEntity *fsm, *next_fsm;

	list_for_each_entry_safe(fsm, next_fsm, &resetInfo.moduleList, node) {
		if (fsm->eModuleType == module) {
			list_del(&fsm->node);
			freeResetFsm(fsm);
		}
	}
}

static void addResetFsm(struct FsmEntity *fsm)
{
	if (!fsm)
		return;

	list_add_tail(&fsm->node, &resetInfo.moduleList);
}

static struct ResetEvent *allocResetEvent(void)
{
	return kmalloc(sizeof(struct ResetEvent), GFP_KERNEL);
}

static void freeResetEvent(struct ResetEvent *event)
{
	if (!event)
		kfree(event);
}

static bool isEventEmpty(void)
{
	mutex_lock(&resetInfo.eventMutex);
	if (list_empty(&resetInfo.eventList)) {
		mutex_unlock(&resetInfo.eventMutex);
		return true;
	}
	mutex_unlock(&resetInfo.eventMutex);
	return false;
}

static void pushResetEvent(struct ResetEvent *event)
{
	if (!event ||
	    ((unsigned int)event->module >= RESET_MODULE_TYPE_MAX) ||
	    ((unsigned int)event->event >= RFSM_EVENT_MAX)) {
		MR_Err("%s: argument error\n", __func__);
		return;
	}

	mutex_lock(&resetInfo.eventMutex);
	list_add_tail(&event->node, &resetInfo.eventList);
	mutex_unlock(&resetInfo.eventMutex);
}

static struct ResetEvent *popResetEvent(void)
{
	struct ResetEvent *event;

	mutex_lock(&resetInfo.eventMutex);
	if (list_empty(&resetInfo.eventList)) {
		mutex_unlock(&resetInfo.eventMutex);
		return NULL;
	}
	event = list_first_entry(&resetInfo.eventList, struct ResetEvent, node);
	list_del(&event->node);
	mutex_unlock(&resetInfo.eventMutex);
	return event;
}

static void removeResetEvent(enum ModuleType module,
			    enum ResetFsmEvent event)
{
	struct ResetEvent *cur, *next;

	mutex_lock(&resetInfo.eventMutex);
	if (list_empty(&resetInfo.eventList)) {
		mutex_unlock(&resetInfo.eventMutex);
		return;
	}
	list_for_each_entry_safe(cur, next, &resetInfo.eventList, node) {
		if ((cur->module == module) &&
		    ((cur->event == event) || (event == RFSM_EVENT_All))) {
			list_del(&cur->node);
			freeResetEvent(cur);
		}
	}
	mutex_unlock(&resetInfo.eventMutex);
}

static int resetko_thread_main(void *data)
{
	struct FsmEntity *fsm;
	struct ResetEvent *resetEvent;
	enum ModuleType module, begin, end;
	int ret = 0;
	unsigned int evt;

	MR_Info("%s: start\n", __func__);

	while (!fgExit) {
		do {
			ret = wait_event_interruptible(resetInfo.resetko_waitq,
						       isEventEmpty() == false);
		} while (ret != 0);

		while (resetEvent = popResetEvent(), resetEvent != NULL) {
			evt = (unsigned int)resetEvent->event;
			if (evt > RFSM_EVENT_MAX)
				continue;
			mutex_lock(&resetInfo.moduleMutex);
			/* check if reset is triggered by BT */
			if ((evt == RFSM_EVENT_TRIGGER_RESET) &&
				(fgIsResetTrigger == false)) {
				if (resetEvent->module == RESET_MODULE_TYPE_BT) {
					fgIsResetTrigger = true;
					fgIsBtTriggered = true;
				} else {
					fgIsResetTrigger = true;
				}
			}
			/* loop for all related module */
			if ((evt == RFSM_EVENT_TRIGGER_RESET) ||
			    (evt == RFSM_EVENT_L0_RESET_GOING) ||
			    (evt == RFSM_EVENT_L0_RESET_DONE)) {
				begin = 0;
				end = RESET_MODULE_TYPE_MAX - 1;
			} else {
				begin = resetEvent->module;
				end = resetEvent->module;
			}
			for (module = begin; module <= end; module++) {
				fsm = findResetFsm(module);
				if (fsm != NULL) {
					if (evt == RFSM_EVENT_L0_RESET_READY)
						fsm->fgReadyForReset = ~false;
					MR_Info("[%s] in [%s] state rcv [%s]\n",
						fsm->name,
						fsm->fsmState->name,
						eventName[evt]);
					resetFsmHandlevent(fsm, evt);
				}
			}
			mutex_unlock(&resetInfo.moduleMutex);
			freeResetEvent(resetEvent);
		}
	}

	MR_Info("%s: stop\n", __func__);

	return 0;
}

void resetkoNotifyEvent(struct FsmEntity *fsm, enum ModuleNotifyEvent event)
{
	if (!fsm) {
		MR_Err("%s: fsm is NULL\n", __func__);
		return;
	}
	if (fsm->notifyFunc != NULL) {
		MR_Info("[%s] %s %d\n", fsm->name, __func__, event);
		fsm->notifyFunc((unsigned int)event, NULL);
	}
}

void clearAllModuleReadyForReset(void)
{
	struct FsmEntity *fsm, *next_fsm;

	/* mutex is hold in function resetko_thread_main */
	list_for_each_entry_safe(fsm, next_fsm, &resetInfo.moduleList, node) {
		fsm->fgReadyForReset = false;
	}
}

bool isAllModuleReadyForReset(void)
{
	struct FsmEntity *fsm, *next_fsm;
	bool ret = ~false;

	/* mutex is hold in function resetko_thread_main */
	list_for_each_entry_safe(fsm, next_fsm, &resetInfo.moduleList, node) {
		MR_Info("[%s] %s: %s\n", fsm->name, __func__,
			fsm->fgReadyForReset ? "ready" : "not ready");
		if (!fsm->fgReadyForReset)
			ret = false;
	}

	/* clear L0ResetDone flag when check all module is ready for reset */
	fgL0ResetDone = false;

	return ret;
}

void callResetFuncByResetApiType(struct FsmEntity *fsm)
{
	struct FsmEntity *cur_fsm, *next_fsm;
	unsigned int i;

	if (fgL0ResetDone) {
		MR_Info("[%s] %s L0ResetDone\n", fsm->name, __func__);
		return;
	}

	for (i = TRIGGER_RESET_TYPE_UNSUPPORT; i < TRIGGER_RESET_API_TYPE_MAX;
	     i++) {
		list_for_each_entry_safe(cur_fsm, next_fsm,
					 &resetInfo.moduleList, node) {
			if (cur_fsm->resetApiType ==
			    TRIGGER_RESET_TYPE_UNSUPPORT){
				MR_Err("[%s] %s module don't support reset\n",
					cur_fsm->name, __func__);
				fgL0ResetDone = true;
				return;
			}
			if ((cur_fsm->resetApiType == i) &&
			    (cur_fsm->resetFunc != NULL)) {
				MR_Info("[%s] %s\n", cur_fsm->name, __func__);
				cur_fsm->resetFunc();
				break;
			}
		}
	}
	fgL0ResetDone = true;

	/* internal send reset done event */
	send_reset_event(fsm->eModuleType, RFSM_EVENT_L0_RESET_DONE);
}


#if KERNEL_VERSION(4, 15, 0) <= LINUX_VERSION_CODE
static void resetkoTimeoutHandler(struct timer_list *timer)
#else
static void resetkoTimeoutHandler(unsigned long arg)
#endif
{
#if KERNEL_VERSION(4, 15, 0) <= LINUX_VERSION_CODE
	struct FsmEntity *fsm = from_timer(fsm, timer, resetTimer);
#else
	struct FsmEntity *fsm = (struct FsmEntity *)arg;
#endif
	if (!fsm) {
		MR_Err("%s: fsm is null\n", __func__);
		return;
	}

	MR_Info("[%s] %s\n", fsm->name, __func__);
	send_reset_event(fsm->eModuleType, RFSM_EVENT_TIMEOUT);
}

void resetkoStartTimer(struct FsmEntity *fsm, unsigned int ms)
{
	if (!fsm) {
		MR_Err("%s: fsm is null\n", __func__);
		return;
	}
	MR_Info("[%s] %s %dms\n", fsm->name, __func__, ms);
	if (ms == 0)
		return;

	mod_timer(&fsm->resetTimer, jiffies + ms * HZ / MSEC_PER_SEC);
}

void resetkoCancleTimer(struct FsmEntity *fsm)
{
	if (!fsm) {
		MR_Err("%s: fsm is null\n", __func__);
		return;
	}
	MR_Info("[%s] %s\n", fsm->name, __func__);

	del_timer(&fsm->resetTimer);
	removeResetEvent(fsm->eModuleType, RFSM_EVENT_TIMEOUT);
}

enum ReturnStatus send_reset_event(enum ModuleType module,
				 enum ResetFsmEvent event)
{
	struct ResetEvent *resetEvent;

	if (((unsigned int)module >= RESET_MODULE_TYPE_MAX) ||
	    ((unsigned int)event >= RFSM_EVENT_MAX)) {
		MR_Err("%s: args error %d %d\n", __func__, module, event);
		return RESET_RETURN_STATUS_FAIL;
	}

	resetEvent = allocResetEvent();
	if (!resetEvent) {
		MR_Err("%s: allocResetEvent fail\n", __func__);
		return RESET_RETURN_STATUS_FAIL;
	}

	MR_Info("[%s] %s %s\n", moduleName[module], __func__, eventName[event]);
	resetEvent->module = module;
	resetEvent->event = event;
	pushResetEvent(resetEvent);

	wake_up_interruptible(&resetInfo.resetko_waitq);

	return RESET_RETURN_STATUS_SUCCESS;
}
EXPORT_SYMBOL(send_reset_event);

enum ReturnStatus send_msg_to_module(enum ModuleType srcModule,
				    enum ModuleType dstModule,
				    void *msg)
{
	struct FsmEntity *srcfsm, *dstfsm;

	if (!msg) {
		MR_Err("%s: %d -> %d, msg is NULL\n",
			__func__, srcModule, dstModule);
	}

	mutex_lock(&resetInfo.moduleMutex);
	srcfsm = findResetFsm(srcModule);
	if (!srcfsm) {
		MR_Err("%s: src module (%d) not exist\n",
			__func__, srcModule);
		goto SEND_MSG_FAIL;
	}
	dstfsm = findResetFsm(dstModule);
	if (!dstfsm) {
		MR_Err("%s: dst module (%d) not exist\n",
			__func__, dstModule);
		goto SEND_MSG_FAIL;
	}
	if (!dstfsm->notifyFunc) {
		MR_Err("%s: dst module (%d) notifyFunc is NULL\n",
			__func__, dstModule);
		goto SEND_MSG_FAIL;
	}
	if (dstfsm->notifyFunc != NULL) {
		MR_Info("%s: module(%s) -> module(%s)\n",
			__func__, srcfsm->name, dstfsm->name);
		dstfsm->notifyFunc((unsigned int)MODULE_NOTIFY_MESSAGE, msg);
	}
	mutex_unlock(&resetInfo.moduleMutex);
	return RESET_RETURN_STATUS_SUCCESS;

SEND_MSG_FAIL:
	mutex_unlock(&resetInfo.moduleMutex);
	return RESET_RETURN_STATUS_FAIL;
}
EXPORT_SYMBOL(send_msg_to_module);


enum ReturnStatus resetko_register_module(enum ModuleType module,
					char *name,
					enum TriggerResetApiType resetApiType,
					void *resetFunc,
					void *notifyFunc)
{
	struct FsmEntity *fsm;

	if (!name) {
		MR_Err("%s: insmod module(%d) with no name\n",
			__func__, module);
		return RESET_RETURN_STATUS_FAIL;
	}
	fsm = allocResetFsm(name, module, resetApiType);
	if (!fsm) {
		MR_Err("%s: allocResetFsm module(%d) fail\n", __func__, module);
		return RESET_RETURN_STATUS_FAIL;
	}
	fsm->notifyFunc = (NotifyFunc)notifyFunc;
	fsm->resetFunc = (ResetFunc)resetFunc;

	mutex_lock(&resetInfo.moduleMutex);
	if (findResetFsm(module) != NULL) {
		freeResetFsm(fsm);
		mutex_unlock(&resetInfo.moduleMutex);
		MR_Err("%s: insmod module(%d) existed\n",
			__func__, module);
		return RESET_RETURN_STATUS_FAIL;
	}

#if (KERNEL_VERSION(4, 15, 0) <= LINUX_VERSION_CODE)
	timer_setup(&fsm->resetTimer, resetkoTimeoutHandler, 0);
#else
	init_timer(&fsm->resetTimer);
	fsm->resetTimer.function = resetkoTimeoutHandler;
	fsm->resetTimer.data = (unsigned long)fsm;
#endif
	memcpy(&moduleName[module][0], fsm->name, RFSM_NAME_MAX_LEN);
	addResetFsm(fsm);
	mutex_unlock(&resetInfo.moduleMutex);

	MR_Info("[%s] %s, module type %d, reset type %d\n",
			name, __func__, module, resetApiType);

	return RESET_RETURN_STATUS_SUCCESS;
}
EXPORT_SYMBOL(resetko_register_module);


enum ReturnStatus resetko_unregister_module(enum ModuleType module)
{
	struct FsmEntity *fsm;

	mutex_lock(&resetInfo.moduleMutex);
	fsm = findResetFsm(module);
	if (!fsm) {
		mutex_unlock(&resetInfo.moduleMutex);
		MR_Err("%s: rmmod module(%d) not exist\n",
			__func__, module);
		return RESET_RETURN_STATUS_SUCCESS;
	}
	resetkoCancleTimer(fsm);
	removeResetEvent(module, RFSM_EVENT_All);

	MR_Info("[%s] %s, module type %d\n", fsm->name, __func__, module);
	removeResetFsm(module);
	mutex_unlock(&resetInfo.moduleMutex);

	return RESET_RETURN_STATUS_SUCCESS;
}
EXPORT_SYMBOL(resetko_unregister_module);


static int __init resetInit(void)
{
	MR_Info("%s\n", __func__);

	fgL0ResetDone = false;
	fgExit = false;

	mutex_init(&resetInfo.moduleMutex);
	mutex_init(&resetInfo.eventMutex);
	INIT_LIST_HEAD(&resetInfo.moduleList);
	INIT_LIST_HEAD(&resetInfo.eventList);
	init_waitqueue_head(&resetInfo.resetko_waitq);
	resetInfo.resetko_thread = kthread_run(resetko_thread_main,
					       NULL, "resetko_thread");

	return 0;
}

static void __exit resetExit(void)
{
	int i;

	for (i = 0; i < RESET_MODULE_TYPE_MAX; i++)
		resetko_unregister_module((enum ModuleType)i);
	fgExit = true;

	MR_Info("%s\n", __func__);
}

module_init(resetInit);
module_exit(resetExit);