1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __FIRMWARE_LOADER_H
3 #define __FIRMWARE_LOADER_H
4
5 #include <linux/bitops.h>
6 #include <linux/firmware.h>
7 #include <linux/types.h>
8 #include <linux/kref.h>
9 #include <linux/list.h>
10 #include <linux/completion.h>
11
12 #include <generated/utsrelease.h>
13
14 /**
15 * enum fw_opt - options to control firmware loading behaviour
16 *
17 * @FW_OPT_UEVENT: Enables the fallback mechanism to send a kobject uevent
18 * when the firmware is not found. Userspace is in charge to load the
19 * firmware using the sysfs loading facility.
20 * @FW_OPT_NOWAIT: Used to describe the firmware request is asynchronous.
21 * @FW_OPT_USERHELPER: Enable the fallback mechanism, in case the direct
22 * filesystem lookup fails at finding the firmware. For details refer to
23 * firmware_fallback_sysfs().
24 * @FW_OPT_NO_WARN: Quiet, avoid printing warning messages.
25 * @FW_OPT_NOCACHE: Disables firmware caching. Firmware caching is used to
26 * cache the firmware upon suspend, so that upon resume races against the
27 * firmware file lookup on storage is avoided. Used for calls where the
28 * file may be too big, or where the driver takes charge of its own
29 * firmware caching mechanism.
30 * @FW_OPT_NOFALLBACK: Disable the fallback mechanism. Takes precedence over
31 * &FW_OPT_UEVENT and &FW_OPT_USERHELPER.
32 */
33 enum fw_opt {
34 FW_OPT_UEVENT = BIT(0),
35 FW_OPT_NOWAIT = BIT(1),
36 FW_OPT_USERHELPER = BIT(2),
37 FW_OPT_NO_WARN = BIT(3),
38 FW_OPT_NOCACHE = BIT(4),
39 FW_OPT_NOFALLBACK = BIT(5),
40 };
41
42 enum fw_status {
43 FW_STATUS_UNKNOWN,
44 FW_STATUS_LOADING,
45 FW_STATUS_DONE,
46 FW_STATUS_ABORTED,
47 };
48
49 /*
50 * Concurrent request_firmware() for the same firmware need to be
51 * serialized. struct fw_state is simple state machine which hold the
52 * state of the firmware loading.
53 */
54 struct fw_state {
55 struct completion completion;
56 enum fw_status status;
57 };
58
59 struct fw_priv {
60 struct kref ref;
61 struct list_head list;
62 struct firmware_cache *fwc;
63 struct fw_state fw_st;
64 void *data;
65 size_t size;
66 size_t allocated_size;
67 #ifdef CONFIG_FW_LOADER_USER_HELPER
68 bool is_paged_buf;
69 bool need_uevent;
70 struct page **pages;
71 int nr_pages;
72 int page_array_size;
73 struct list_head pending_list;
74 #endif
75 const char *fw_name;
76 };
77
78 extern struct mutex fw_lock;
79
__fw_state_check(struct fw_priv * fw_priv,enum fw_status status)80 static inline bool __fw_state_check(struct fw_priv *fw_priv,
81 enum fw_status status)
82 {
83 struct fw_state *fw_st = &fw_priv->fw_st;
84
85 return fw_st->status == status;
86 }
87
__fw_state_wait_common(struct fw_priv * fw_priv,long timeout)88 static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout)
89 {
90 struct fw_state *fw_st = &fw_priv->fw_st;
91 long ret;
92
93 ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout);
94 if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
95 return -ENOENT;
96 if (!ret)
97 return -ETIMEDOUT;
98
99 return ret < 0 ? ret : 0;
100 }
101
__fw_state_set(struct fw_priv * fw_priv,enum fw_status status)102 static inline void __fw_state_set(struct fw_priv *fw_priv,
103 enum fw_status status)
104 {
105 struct fw_state *fw_st = &fw_priv->fw_st;
106
107 WRITE_ONCE(fw_st->status, status);
108
109 if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
110 complete_all(&fw_st->completion);
111 }
112
fw_state_aborted(struct fw_priv * fw_priv)113 static inline void fw_state_aborted(struct fw_priv *fw_priv)
114 {
115 __fw_state_set(fw_priv, FW_STATUS_ABORTED);
116 }
117
fw_state_is_aborted(struct fw_priv * fw_priv)118 static inline bool fw_state_is_aborted(struct fw_priv *fw_priv)
119 {
120 return __fw_state_check(fw_priv, FW_STATUS_ABORTED);
121 }
122
fw_state_start(struct fw_priv * fw_priv)123 static inline void fw_state_start(struct fw_priv *fw_priv)
124 {
125 __fw_state_set(fw_priv, FW_STATUS_LOADING);
126 }
127
fw_state_done(struct fw_priv * fw_priv)128 static inline void fw_state_done(struct fw_priv *fw_priv)
129 {
130 __fw_state_set(fw_priv, FW_STATUS_DONE);
131 }
132
133 int assign_fw(struct firmware *fw, struct device *device,
134 enum fw_opt opt_flags);
135
136 #endif /* __FIRMWARE_LOADER_H */
137
