1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2015, Sony Mobile Communications Inc.
* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
*/
#include <linux/device.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/soc/qcom/smem_state.h>
static LIST_HEAD(smem_states);
static DEFINE_MUTEX(list_lock);
/**
* struct qcom_smem_state - state context
* @refcount: refcount for the state
* @orphan: boolean indicator that this state has been unregistered
* @list: entry in smem_states list
* @of_node: of_node to use for matching the state in DT
* @priv: implementation private data
* @ops: ops for the state
*/
struct qcom_smem_state {
struct kref refcount;
bool orphan;
struct list_head list;
struct device_node *of_node;
void *priv;
struct qcom_smem_state_ops ops;
};
/**
* qcom_smem_state_update_bits() - update the masked bits in state with value
* @state: state handle acquired by calling qcom_smem_state_get()
* @mask: bit mask for the change
* @value: new value for the masked bits
*
* Returns 0 on success, otherwise negative errno.
*/
int qcom_smem_state_update_bits(struct qcom_smem_state *state,
u32 mask,
u32 value)
{
if (state->orphan)
return -ENXIO;
if (!state->ops.update_bits)
return -ENOTSUPP;
return state->ops.update_bits(state->priv, mask, value);
}
EXPORT_SYMBOL_GPL(qcom_smem_state_update_bits);
static struct qcom_smem_state *of_node_to_state(struct device_node *np)
{
struct qcom_smem_state *state;
mutex_lock(&list_lock);
list_for_each_entry(state, &smem_states, list) {
if (state->of_node == np) {
kref_get(&state->refcount);
goto unlock;
}
}
state = ERR_PTR(-EPROBE_DEFER);
unlock:
mutex_unlock(&list_lock);
return state;
}
/**
* qcom_smem_state_get() - acquire handle to a state
* @dev: client device pointer
* @con_id: name of the state to lookup
* @bit: flags from the state reference, indicating which bit's affected
*
* Returns handle to the state, or ERR_PTR(). qcom_smem_state_put() must be
* called to release the returned state handle.
*/
struct qcom_smem_state *qcom_smem_state_get(struct device *dev,
const char *con_id,
unsigned *bit)
{
struct qcom_smem_state *state;
struct of_phandle_args args;
int index = 0;
int ret;
if (con_id) {
index = of_property_match_string(dev->of_node,
"qcom,smem-state-names",
con_id);
if (index < 0) {
dev_err(dev, "missing qcom,smem-state-names\n");
return ERR_PTR(index);
}
}
ret = of_parse_phandle_with_args(dev->of_node,
"qcom,smem-states",
"#qcom,smem-state-cells",
index,
&args);
if (ret) {
dev_err(dev, "failed to parse qcom,smem-states property\n");
return ERR_PTR(ret);
}
if (args.args_count != 1) {
dev_err(dev, "invalid #qcom,smem-state-cells\n");
return ERR_PTR(-EINVAL);
}
state = of_node_to_state(args.np);
if (IS_ERR(state))
goto put;
*bit = args.args[0];
put:
of_node_put(args.np);
return state;
}
EXPORT_SYMBOL_GPL(qcom_smem_state_get);
static void qcom_smem_state_release(struct kref *ref)
{
struct qcom_smem_state *state = container_of(ref, struct qcom_smem_state, refcount);
list_del(&state->list);
kfree(state);
}
/**
* qcom_smem_state_put() - release state handle
* @state: state handle to be released
*/
void qcom_smem_state_put(struct qcom_smem_state *state)
{
mutex_lock(&list_lock);
kref_put(&state->refcount, qcom_smem_state_release);
mutex_unlock(&list_lock);
}
EXPORT_SYMBOL_GPL(qcom_smem_state_put);
/**
* qcom_smem_state_register() - register a new state
* @of_node: of_node used for matching client lookups
* @ops: implementation ops
* @priv: implementation specific private data
*/
struct qcom_smem_state *qcom_smem_state_register(struct device_node *of_node,
const struct qcom_smem_state_ops *ops,
void *priv)
{
struct qcom_smem_state *state;
state = kzalloc(sizeof(*state), GFP_KERNEL);
if (!state)
return ERR_PTR(-ENOMEM);
kref_init(&state->refcount);
state->of_node = of_node;
state->ops = *ops;
state->priv = priv;
mutex_lock(&list_lock);
list_add(&state->list, &smem_states);
mutex_unlock(&list_lock);
return state;
}
EXPORT_SYMBOL_GPL(qcom_smem_state_register);
/**
* qcom_smem_state_unregister() - unregister a registered state
* @state: state handle to be unregistered
*/
void qcom_smem_state_unregister(struct qcom_smem_state *state)
{
state->orphan = true;
qcom_smem_state_put(state);
}
EXPORT_SYMBOL_GPL(qcom_smem_state_unregister);
|
