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_SYSFS: Disable the sysfs fallback mechanism. Takes
31 * precedence over &FW_OPT_UEVENT and &FW_OPT_USERHELPER.
32 * @FW_OPT_FALLBACK_PLATFORM: Enable fallback to device fw copy embedded in
33 * the platform's main firmware. If both this fallback and the sysfs
34 * fallback are enabled, then this fallback will be tried first.
35 * @FW_OPT_PARTIAL: Allow partial read of firmware instead of needing to read
36 * entire file.
37 */
38 enum fw_opt {
39 FW_OPT_UEVENT = BIT(0),
40 FW_OPT_NOWAIT = BIT(1),
41 FW_OPT_USERHELPER = BIT(2),
42 FW_OPT_NO_WARN = BIT(3),
43 FW_OPT_NOCACHE = BIT(4),
44 FW_OPT_NOFALLBACK_SYSFS = BIT(5),
45 FW_OPT_FALLBACK_PLATFORM = BIT(6),
46 FW_OPT_PARTIAL = BIT(7),
47 };
48
49 enum fw_status {
50 FW_STATUS_UNKNOWN,
51 FW_STATUS_LOADING,
52 FW_STATUS_DONE,
53 FW_STATUS_ABORTED,
54 };
55
56 /*
57 * Concurrent request_firmware() for the same firmware need to be
58 * serialized. struct fw_state is simple state machine which hold the
59 * state of the firmware loading.
60 */
61 struct fw_state {
62 struct completion completion;
63 enum fw_status status;
64 };
65
66 struct fw_priv {
67 struct kref ref;
68 struct list_head list;
69 struct firmware_cache *fwc;
70 struct fw_state fw_st;
71 void *data;
72 size_t size;
73 size_t allocated_size;
74 size_t offset;
75 u32 opt_flags;
76 #ifdef CONFIG_FW_LOADER_PAGED_BUF
77 bool is_paged_buf;
78 struct page **pages;
79 int nr_pages;
80 int page_array_size;
81 #endif
82 #ifdef CONFIG_FW_LOADER_USER_HELPER
83 bool need_uevent;
84 struct list_head pending_list;
85 #endif
86 const char *fw_name;
87 };
88
89 extern struct mutex fw_lock;
90
__fw_state_check(struct fw_priv * fw_priv,enum fw_status status)91 static inline bool __fw_state_check(struct fw_priv *fw_priv,
92 enum fw_status status)
93 {
94 struct fw_state *fw_st = &fw_priv->fw_st;
95
96 return fw_st->status == status;
97 }
98
__fw_state_wait_common(struct fw_priv * fw_priv,long timeout)99 static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout)
100 {
101 struct fw_state *fw_st = &fw_priv->fw_st;
102 long ret;
103
104 ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout);
105 if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
106 return -ENOENT;
107 if (!ret)
108 return -ETIMEDOUT;
109
110 return ret < 0 ? ret : 0;
111 }
112
__fw_state_set(struct fw_priv * fw_priv,enum fw_status status)113 static inline void __fw_state_set(struct fw_priv *fw_priv,
114 enum fw_status status)
115 {
116 struct fw_state *fw_st = &fw_priv->fw_st;
117
118 WRITE_ONCE(fw_st->status, status);
119
120 if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
121 complete_all(&fw_st->completion);
122 }
123
fw_state_aborted(struct fw_priv * fw_priv)124 static inline void fw_state_aborted(struct fw_priv *fw_priv)
125 {
126 __fw_state_set(fw_priv, FW_STATUS_ABORTED);
127 }
128
fw_state_is_aborted(struct fw_priv * fw_priv)129 static inline bool fw_state_is_aborted(struct fw_priv *fw_priv)
130 {
131 return __fw_state_check(fw_priv, FW_STATUS_ABORTED);
132 }
133
fw_state_start(struct fw_priv * fw_priv)134 static inline void fw_state_start(struct fw_priv *fw_priv)
135 {
136 __fw_state_set(fw_priv, FW_STATUS_LOADING);
137 }
138
fw_state_done(struct fw_priv * fw_priv)139 static inline void fw_state_done(struct fw_priv *fw_priv)
140 {
141 __fw_state_set(fw_priv, FW_STATUS_DONE);
142 }
143
144 int assign_fw(struct firmware *fw, struct device *device);
145
146 #ifdef CONFIG_FW_LOADER_PAGED_BUF
147 void fw_free_paged_buf(struct fw_priv *fw_priv);
148 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed);
149 int fw_map_paged_buf(struct fw_priv *fw_priv);
150 bool fw_is_paged_buf(struct fw_priv *fw_priv);
151 #else
fw_free_paged_buf(struct fw_priv * fw_priv)152 static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {}
fw_grow_paged_buf(struct fw_priv * fw_priv,int pages_needed)153 static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; }
fw_map_paged_buf(struct fw_priv * fw_priv)154 static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; }
fw_is_paged_buf(struct fw_priv * fw_priv)155 static inline bool fw_is_paged_buf(struct fw_priv *fw_priv) { return false; }
156 #endif
157
158 #endif /* __FIRMWARE_LOADER_H */
159
