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 */ 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 }; 45 46 enum fw_status { 47 FW_STATUS_UNKNOWN, 48 FW_STATUS_LOADING, 49 FW_STATUS_DONE, 50 FW_STATUS_ABORTED, 51 }; 52 53 /* 54 * Concurrent request_firmware() for the same firmware need to be 55 * serialized. struct fw_state is simple state machine which hold the 56 * state of the firmware loading. 57 */ 58 struct fw_state { 59 struct completion completion; 60 enum fw_status status; 61 }; 62 63 struct fw_priv { 64 struct kref ref; 65 struct list_head list; 66 struct firmware_cache *fwc; 67 struct fw_state fw_st; 68 void *data; 69 size_t size; 70 size_t allocated_size; 71 #ifdef CONFIG_FW_LOADER_PAGED_BUF 72 bool is_paged_buf; 73 struct page **pages; 74 int nr_pages; 75 int page_array_size; 76 #endif 77 #ifdef CONFIG_FW_LOADER_USER_HELPER 78 bool need_uevent; 79 struct list_head pending_list; 80 #endif 81 const char *fw_name; 82 }; 83 84 extern struct mutex fw_lock; 85 86 static inline bool __fw_state_check(struct fw_priv *fw_priv, 87 enum fw_status status) 88 { 89 struct fw_state *fw_st = &fw_priv->fw_st; 90 91 return fw_st->status == status; 92 } 93 94 static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout) 95 { 96 struct fw_state *fw_st = &fw_priv->fw_st; 97 long ret; 98 99 ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout); 100 if (ret != 0 && fw_st->status == FW_STATUS_ABORTED) 101 return -ENOENT; 102 if (!ret) 103 return -ETIMEDOUT; 104 105 return ret < 0 ? ret : 0; 106 } 107 108 static inline void __fw_state_set(struct fw_priv *fw_priv, 109 enum fw_status status) 110 { 111 struct fw_state *fw_st = &fw_priv->fw_st; 112 113 WRITE_ONCE(fw_st->status, status); 114 115 if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED) 116 complete_all(&fw_st->completion); 117 } 118 119 static inline void fw_state_aborted(struct fw_priv *fw_priv) 120 { 121 __fw_state_set(fw_priv, FW_STATUS_ABORTED); 122 } 123 124 static inline bool fw_state_is_aborted(struct fw_priv *fw_priv) 125 { 126 return __fw_state_check(fw_priv, FW_STATUS_ABORTED); 127 } 128 129 static inline void fw_state_start(struct fw_priv *fw_priv) 130 { 131 __fw_state_set(fw_priv, FW_STATUS_LOADING); 132 } 133 134 static inline void fw_state_done(struct fw_priv *fw_priv) 135 { 136 __fw_state_set(fw_priv, FW_STATUS_DONE); 137 } 138 139 int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags); 140 141 #ifdef CONFIG_FW_LOADER_PAGED_BUF 142 void fw_free_paged_buf(struct fw_priv *fw_priv); 143 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed); 144 int fw_map_paged_buf(struct fw_priv *fw_priv); 145 #else 146 static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {} 147 static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; } 148 static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; } 149 #endif 150 151 #endif /* __FIRMWARE_LOADER_H */ 152