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 extern struct firmware_cache fw_cache; 91 92 static inline bool __fw_state_check(struct fw_priv *fw_priv, 93 enum fw_status status) 94 { 95 struct fw_state *fw_st = &fw_priv->fw_st; 96 97 return fw_st->status == status; 98 } 99 100 static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout) 101 { 102 struct fw_state *fw_st = &fw_priv->fw_st; 103 long ret; 104 105 ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout); 106 if (ret != 0 && fw_st->status == FW_STATUS_ABORTED) 107 return -ENOENT; 108 if (!ret) 109 return -ETIMEDOUT; 110 111 return ret < 0 ? ret : 0; 112 } 113 114 static inline void __fw_state_set(struct fw_priv *fw_priv, 115 enum fw_status status) 116 { 117 struct fw_state *fw_st = &fw_priv->fw_st; 118 119 WRITE_ONCE(fw_st->status, status); 120 121 if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED) { 122 #ifdef CONFIG_FW_LOADER_USER_HELPER 123 /* 124 * Doing this here ensures that the fw_priv is deleted from 125 * the pending list in all abort/done paths. 126 */ 127 list_del_init(&fw_priv->pending_list); 128 #endif 129 complete_all(&fw_st->completion); 130 } 131 } 132 133 static inline void fw_state_aborted(struct fw_priv *fw_priv) 134 { 135 __fw_state_set(fw_priv, FW_STATUS_ABORTED); 136 } 137 138 static inline bool fw_state_is_aborted(struct fw_priv *fw_priv) 139 { 140 return __fw_state_check(fw_priv, FW_STATUS_ABORTED); 141 } 142 143 static inline void fw_state_start(struct fw_priv *fw_priv) 144 { 145 __fw_state_set(fw_priv, FW_STATUS_LOADING); 146 } 147 148 static inline void fw_state_done(struct fw_priv *fw_priv) 149 { 150 __fw_state_set(fw_priv, FW_STATUS_DONE); 151 } 152 153 static inline bool fw_state_is_done(struct fw_priv *fw_priv) 154 { 155 return __fw_state_check(fw_priv, FW_STATUS_DONE); 156 } 157 158 static inline bool fw_state_is_loading(struct fw_priv *fw_priv) 159 { 160 return __fw_state_check(fw_priv, FW_STATUS_LOADING); 161 } 162 163 int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc, 164 struct fw_priv **fw_priv, void *dbuf, size_t size, 165 size_t offset, u32 opt_flags); 166 int assign_fw(struct firmware *fw, struct device *device); 167 void free_fw_priv(struct fw_priv *fw_priv); 168 void fw_state_init(struct fw_priv *fw_priv); 169 170 #ifdef CONFIG_FW_LOADER 171 bool firmware_is_builtin(const struct firmware *fw); 172 bool firmware_request_builtin_buf(struct firmware *fw, const char *name, 173 void *buf, size_t size); 174 #else /* module case */ 175 static inline bool firmware_is_builtin(const struct firmware *fw) 176 { 177 return false; 178 } 179 static inline bool firmware_request_builtin_buf(struct firmware *fw, 180 const char *name, 181 void *buf, size_t size) 182 { 183 return false; 184 } 185 #endif 186 187 #ifdef CONFIG_FW_LOADER_PAGED_BUF 188 void fw_free_paged_buf(struct fw_priv *fw_priv); 189 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed); 190 int fw_map_paged_buf(struct fw_priv *fw_priv); 191 bool fw_is_paged_buf(struct fw_priv *fw_priv); 192 #else 193 static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {} 194 static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; } 195 static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; } 196 static inline bool fw_is_paged_buf(struct fw_priv *fw_priv) { return false; } 197 #endif 198 199 #endif /* __FIRMWARE_LOADER_H */ 200