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