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 /** 13 * enum fw_opt - options to control firmware loading behaviour 14 * 15 * @FW_OPT_UEVENT: Enables the fallback mechanism to send a kobject uevent 16 * when the firmware is not found. Userspace is in charge to load the 17 * firmware using the sysfs loading facility. 18 * @FW_OPT_NOWAIT: Used to describe the firmware request is asynchronous. 19 * @FW_OPT_USERHELPER: Enable the fallback mechanism, in case the direct 20 * filesystem lookup fails at finding the firmware. For details refer to 21 * firmware_fallback_sysfs(). 22 * @FW_OPT_NO_WARN: Quiet, avoid printing warning messages. 23 * @FW_OPT_NOCACHE: Disables firmware caching. Firmware caching is used to 24 * cache the firmware upon suspend, so that upon resume races against the 25 * firmware file lookup on storage is avoided. Used for calls where the 26 * file may be too big, or where the driver takes charge of its own 27 * firmware caching mechanism. 28 * @FW_OPT_NOFALLBACK_SYSFS: Disable the sysfs fallback mechanism. Takes 29 * precedence over &FW_OPT_UEVENT and &FW_OPT_USERHELPER. 30 * @FW_OPT_FALLBACK_PLATFORM: Enable fallback to device fw copy embedded in 31 * the platform's main firmware. If both this fallback and the sysfs 32 * fallback are enabled, then this fallback will be tried first. 33 * @FW_OPT_PARTIAL: Allow partial read of firmware instead of needing to read 34 * entire file. 35 */ 36 enum fw_opt { 37 FW_OPT_UEVENT = BIT(0), 38 FW_OPT_NOWAIT = BIT(1), 39 FW_OPT_USERHELPER = BIT(2), 40 FW_OPT_NO_WARN = BIT(3), 41 FW_OPT_NOCACHE = BIT(4), 42 FW_OPT_NOFALLBACK_SYSFS = BIT(5), 43 FW_OPT_FALLBACK_PLATFORM = BIT(6), 44 FW_OPT_PARTIAL = BIT(7), 45 }; 46 47 enum fw_status { 48 FW_STATUS_UNKNOWN, 49 FW_STATUS_LOADING, 50 FW_STATUS_DONE, 51 FW_STATUS_ABORTED, 52 }; 53 54 /* 55 * Concurrent request_firmware() for the same firmware need to be 56 * serialized. struct fw_state is simple state machine which hold the 57 * state of the firmware loading. 58 */ 59 struct fw_state { 60 struct completion completion; 61 enum fw_status status; 62 }; 63 64 struct fw_priv { 65 struct kref ref; 66 struct list_head list; 67 struct firmware_cache *fwc; 68 struct fw_state fw_st; 69 void *data; 70 size_t size; 71 size_t allocated_size; 72 size_t offset; 73 u32 opt_flags; 74 #ifdef CONFIG_FW_LOADER_PAGED_BUF 75 bool is_paged_buf; 76 struct page **pages; 77 int nr_pages; 78 int page_array_size; 79 #endif 80 #ifdef CONFIG_FW_LOADER_USER_HELPER 81 bool need_uevent; 82 struct list_head pending_list; 83 #endif 84 const char *fw_name; 85 }; 86 87 extern struct mutex fw_lock; 88 extern struct firmware_cache fw_cache; 89 extern bool fw_load_abort_all; 90 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 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 } 112 113 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 #ifdef CONFIG_FW_LOADER_USER_HELPER 122 /* 123 * Doing this here ensures that the fw_priv is deleted from 124 * the pending list in all abort/done paths. 125 */ 126 list_del_init(&fw_priv->pending_list); 127 #endif 128 complete_all(&fw_st->completion); 129 } 130 } 131 132 static inline void fw_state_aborted(struct fw_priv *fw_priv) 133 { 134 __fw_state_set(fw_priv, FW_STATUS_ABORTED); 135 } 136 137 static inline bool fw_state_is_aborted(struct fw_priv *fw_priv) 138 { 139 return __fw_state_check(fw_priv, FW_STATUS_ABORTED); 140 } 141 142 static inline void fw_state_start(struct fw_priv *fw_priv) 143 { 144 __fw_state_set(fw_priv, FW_STATUS_LOADING); 145 } 146 147 static inline void fw_state_done(struct fw_priv *fw_priv) 148 { 149 __fw_state_set(fw_priv, FW_STATUS_DONE); 150 } 151 152 static inline bool fw_state_is_done(struct fw_priv *fw_priv) 153 { 154 return __fw_state_check(fw_priv, FW_STATUS_DONE); 155 } 156 157 static inline bool fw_state_is_loading(struct fw_priv *fw_priv) 158 { 159 return __fw_state_check(fw_priv, FW_STATUS_LOADING); 160 } 161 162 int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc, 163 struct fw_priv **fw_priv, void *dbuf, size_t size, 164 size_t offset, u32 opt_flags); 165 int assign_fw(struct firmware *fw, struct device *device); 166 void free_fw_priv(struct fw_priv *fw_priv); 167 void fw_state_init(struct fw_priv *fw_priv); 168 169 #ifdef CONFIG_FW_LOADER 170 bool firmware_is_builtin(const struct firmware *fw); 171 bool firmware_request_builtin_buf(struct firmware *fw, const char *name, 172 void *buf, size_t size); 173 #else /* module case */ 174 static inline bool firmware_is_builtin(const struct firmware *fw) 175 { 176 return false; 177 } 178 static inline bool firmware_request_builtin_buf(struct firmware *fw, 179 const char *name, 180 void *buf, size_t size) 181 { 182 return false; 183 } 184 #endif 185 186 #ifdef CONFIG_FW_LOADER_PAGED_BUF 187 void fw_free_paged_buf(struct fw_priv *fw_priv); 188 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed); 189 int fw_map_paged_buf(struct fw_priv *fw_priv); 190 bool fw_is_paged_buf(struct fw_priv *fw_priv); 191 #else 192 static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {} 193 static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; } 194 static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; } 195 static inline bool fw_is_paged_buf(struct fw_priv *fw_priv) { return false; } 196 #endif 197 198 #endif /* __FIRMWARE_LOADER_H */ 199