1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2008, Creative Technology Ltd. All Rights Reserved.
4 *
5 * @File	ctimap.c
6 *
7 * @Brief
8 * This file contains the implementation of generic input mapper operations
9 * for input mapper management.
10 *
11 * @Author	Liu Chun
12 * @Date 	May 23 2008
13 */
14
15#include "ctimap.h"
16#include <linux/slab.h>
17
18int input_mapper_add(struct list_head *mappers, struct imapper *entry,
19		     int (*map_op)(void *, struct imapper *), void *data)
20{
21	struct list_head *pos, *pre, *head;
22	struct imapper *pre_ent, *pos_ent;
23
24	head = mappers;
25
26	if (list_empty(head)) {
27		entry->next = entry->addr;
28		map_op(data, entry);
29		list_add(&entry->list, head);
30		return 0;
31	}
32
33	list_for_each(pos, head) {
34		pos_ent = list_entry(pos, struct imapper, list);
35		if (pos_ent->slot > entry->slot) {
36			/* found a position in list */
37			break;
38		}
39	}
40
41	if (pos != head) {
42		pre = pos->prev;
43		if (pre == head)
44			pre = head->prev;
45
46		__list_add(&entry->list, pos->prev, pos);
47	} else {
48		pre = head->prev;
49		pos = head->next;
50		list_add_tail(&entry->list, head);
51	}
52
53	pre_ent = list_entry(pre, struct imapper, list);
54	pos_ent = list_entry(pos, struct imapper, list);
55
56	entry->next = pos_ent->addr;
57	map_op(data, entry);
58	pre_ent->next = entry->addr;
59	map_op(data, pre_ent);
60
61	return 0;
62}
63
64int input_mapper_delete(struct list_head *mappers, struct imapper *entry,
65		     int (*map_op)(void *, struct imapper *), void *data)
66{
67	struct list_head *next, *pre, *head;
68	struct imapper *pre_ent, *next_ent;
69
70	head = mappers;
71
72	if (list_empty(head))
73		return 0;
74
75	pre = (entry->list.prev == head) ? head->prev : entry->list.prev;
76	next = (entry->list.next == head) ? head->next : entry->list.next;
77
78	if (pre == &entry->list) {
79		/* entry is the only one node in mappers list */
80		entry->next = entry->addr = entry->user = entry->slot = 0;
81		map_op(data, entry);
82		list_del(&entry->list);
83		return 0;
84	}
85
86	pre_ent = list_entry(pre, struct imapper, list);
87	next_ent = list_entry(next, struct imapper, list);
88
89	pre_ent->next = next_ent->addr;
90	map_op(data, pre_ent);
91	list_del(&entry->list);
92
93	return 0;
94}
95
96void free_input_mapper_list(struct list_head *head)
97{
98	struct imapper *entry;
99	struct list_head *pos;
100
101	while (!list_empty(head)) {
102		pos = head->next;
103		list_del(pos);
104		entry = list_entry(pos, struct imapper, list);
105		kfree(entry);
106	}
107}
108
109