summaryrefslogtreecommitdiff
path: root/drivers/base/firmware_loader/firmware.h
blob: 7ecd590e67fe1f11829d6aa6bd3fd78b21f04497 (plain)
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
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __FIRMWARE_LOADER_H
#define __FIRMWARE_LOADER_H

#include <linux/bitops.h>
#include <linux/firmware.h>
#include <linux/types.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/completion.h>

#include <generated/utsrelease.h>

/**
 * enum fw_opt - options to control firmware loading behaviour
 *
 * @FW_OPT_UEVENT: Enables the fallback mechanism to send a kobject uevent
 *	when the firmware is not found. Userspace is in charge to load the
 *	firmware using the sysfs loading facility.
 * @FW_OPT_NOWAIT: Used to describe the firmware request is asynchronous.
 * @FW_OPT_USERHELPER: Enable the fallback mechanism, in case the direct
 *	filesystem lookup fails at finding the firmware.  For details refer to
 *	firmware_fallback_sysfs().
 * @FW_OPT_NO_WARN: Quiet, avoid printing warning messages.
 * @FW_OPT_NOCACHE: Disables firmware caching. Firmware caching is used to
 *	cache the firmware upon suspend, so that upon resume races against the
 *	firmware file lookup on storage is avoided. Used for calls where the
 *	file may be too big, or where the driver takes charge of its own
 *	firmware caching mechanism.
 * @FW_OPT_NOFALLBACK: Disable the fallback mechanism. Takes precedence over
 *	&FW_OPT_UEVENT and &FW_OPT_USERHELPER.
 */
enum fw_opt {
	FW_OPT_UEVENT =         BIT(0),
	FW_OPT_NOWAIT =         BIT(1),
	FW_OPT_USERHELPER =     BIT(2),
	FW_OPT_NO_WARN =        BIT(3),
	FW_OPT_NOCACHE =        BIT(4),
	FW_OPT_NOFALLBACK =     BIT(5),
};

enum fw_status {
	FW_STATUS_UNKNOWN,
	FW_STATUS_LOADING,
	FW_STATUS_DONE,
	FW_STATUS_ABORTED,
};

/*
 * Concurrent request_firmware() for the same firmware need to be
 * serialized.  struct fw_state is simple state machine which hold the
 * state of the firmware loading.
 */
struct fw_state {
	struct completion completion;
	enum fw_status status;
};

struct fw_priv {
	struct kref ref;
	struct list_head list;
	struct firmware_cache *fwc;
	struct fw_state fw_st;
	void *data;
	size_t size;
	size_t allocated_size;
#ifdef CONFIG_FW_LOADER_PAGED_BUF
	bool is_paged_buf;
	struct page **pages;
	int nr_pages;
	int page_array_size;
#endif
#ifdef CONFIG_FW_LOADER_USER_HELPER
	bool need_uevent;
	struct list_head pending_list;
#endif
	const char *fw_name;
};

extern struct mutex fw_lock;

static inline bool __fw_state_check(struct fw_priv *fw_priv,
				    enum fw_status status)
{
	struct fw_state *fw_st = &fw_priv->fw_st;

	return fw_st->status == status;
}

static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout)
{
	struct fw_state *fw_st = &fw_priv->fw_st;
	long ret;

	ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout);
	if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
		return -ENOENT;
	if (!ret)
		return -ETIMEDOUT;

	return ret < 0 ? ret : 0;
}

static inline void __fw_state_set(struct fw_priv *fw_priv,
				  enum fw_status status)
{
	struct fw_state *fw_st = &fw_priv->fw_st;

	WRITE_ONCE(fw_st->status, status);

	if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
		complete_all(&fw_st->completion);
}

static inline void fw_state_aborted(struct fw_priv *fw_priv)
{
	__fw_state_set(fw_priv, FW_STATUS_ABORTED);
}

static inline bool fw_state_is_aborted(struct fw_priv *fw_priv)
{
	return __fw_state_check(fw_priv, FW_STATUS_ABORTED);
}

static inline void fw_state_start(struct fw_priv *fw_priv)
{
	__fw_state_set(fw_priv, FW_STATUS_LOADING);
}

static inline void fw_state_done(struct fw_priv *fw_priv)
{
	__fw_state_set(fw_priv, FW_STATUS_DONE);
}

int assign_fw(struct firmware *fw, struct device *device,
	      enum fw_opt opt_flags);

#ifdef CONFIG_FW_LOADER_PAGED_BUF
void fw_free_paged_buf(struct fw_priv *fw_priv);
int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed);
int fw_map_paged_buf(struct fw_priv *fw_priv);
#else
static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {}
static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; }
static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; }
#endif

#endif /* __FIRMWARE_LOADER_H */