1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Keyboard input helper functions (too small to be called a layer) 4 * 5 * Copyright (c) 2011 The Chromium OS Authors. 6 */ 7 8 #ifndef _INPUT_H 9 #define _INPUT_H 10 11 enum { 12 INPUT_MAX_MODIFIERS = 4, 13 INPUT_BUFFER_LEN = 16, 14 }; 15 16 enum { 17 /* Keyboard LEDs */ 18 INPUT_LED_SCROLL = 1 << 0, 19 INPUT_LED_NUM = 1 << 1, 20 INPUT_LED_CAPS = 1 << 2, 21 }; 22 23 /* 24 * This table translates key codes to ASCII. Most of the entries are ASCII 25 * codes, but entries after KEY_FIRST_MOD indicate that this key is a 26 * modifier key, like shift, ctrl. KEY_FIRST_MOD + MOD_SHIFT is the shift 27 * key, for example. 28 */ 29 struct input_key_xlate { 30 /* keycode of the modifiers which select this table, -1 if none */ 31 int left_keycode; 32 int right_keycode; 33 const uchar *xlate; /* keycode to ASCII table */ 34 int num_entries; /* number of entries in this table */ 35 }; 36 37 struct input_config { 38 struct udevice *dev; 39 uchar fifo[INPUT_BUFFER_LEN]; 40 int fifo_in, fifo_out; 41 42 /* Which modifiers are active (1 bit for each MOD_... value) */ 43 uchar modifiers; 44 uchar flags; /* active state keys (FLAGS_...) */ 45 uchar leds; /* active LEDs (INPUT_LED_...) */ 46 uchar leds_changed; /* LEDs that just changed */ 47 uchar num_tables; /* number of modifier tables */ 48 int prev_keycodes[INPUT_BUFFER_LEN]; /* keys held last time */ 49 int num_prev_keycodes; /* number of prev keys */ 50 struct input_key_xlate table[INPUT_MAX_MODIFIERS]; 51 52 /** 53 * Function the input helper calls to scan the keyboard 54 * 55 * @param config Input state 56 * @return 0 if no keys read, otherwise number of keys read, or 1 if 57 * unknown 58 */ 59 int (*read_keys)(struct input_config *config); 60 bool allow_repeats; /* Don't filter out repeats */ 61 unsigned int next_repeat_ms; /* Next time we repeat a key */ 62 unsigned int repeat_delay_ms; /* Time before autorepeat starts */ 63 unsigned int repeat_rate_ms; /* Autorepeat rate in ms */ 64 }; 65 66 struct stdio_dev; 67 68 /** 69 * Convert a list of key codes into ASCII and send them 70 * 71 * @param config Input state 72 * @param keycode List of key codes to examine 73 * @param num_keycodes Number of key codes 74 * @return number of ascii characters sent, or 0 if none, or -1 for an 75 * internal error 76 */ 77 int input_send_keycodes(struct input_config *config, int keycode[], int count); 78 79 /** 80 * Add a new keycode to an existing list of keycodes 81 * 82 * This can be used to handle keyboards which do their own scanning. An 83 * internal list of depressed keys is maintained by the input library. Then 84 * this function is called to add a new key to the list (when a 'make code' is 85 * received), or remove a key (when a 'break code' is received). 86 * 87 * This function looks after maintenance of the list of active keys, and calls 88 * input_send_keycodes() with its updated list. 89 * 90 * @param config Input state 91 * @param new_keycode New keycode to add/remove 92 * @param release true if this key was released, false if depressed 93 * @return number of ascii characters sent, or 0 if none, or -1 for an 94 * internal error 95 */ 96 int input_add_keycode(struct input_config *config, int new_keycode, 97 bool release); 98 99 /** 100 * Add a new key translation table to the input 101 * 102 * @param config Input state 103 * @param left_keycode Key to hold to get into this table 104 * @param right_keycode Another key to hold to get into this table 105 * @param xlate Conversion table from key codes to ASCII 106 * @param num_entries Number of entries in xlate table 107 */ 108 int input_add_table(struct input_config *config, int left_keycode, 109 int right_keycode, const uchar *xlate, int num_entries); 110 111 /** 112 * Test if keys are available to be read 113 * 114 * @param config Input state 115 * @return 0 if no keys available, 1 if keys are available 116 */ 117 int input_tstc(struct input_config *config); 118 119 /** 120 * Read a key 121 * 122 * TODO: U-Boot wants 0 for no key, but Ctrl-@ is a valid key... 123 * 124 * @param config Input state 125 * @return key, or 0 if no key, or -1 if error 126 */ 127 int input_getc(struct input_config *config); 128 129 /** 130 * Register a new device with stdio and switch to it if wanted 131 * 132 * @param dev Pointer to device 133 * @return 0 if ok, -1 on error 134 */ 135 int input_stdio_register(struct stdio_dev *dev); 136 137 /** 138 * Set up the keyboard autorepeat delays 139 * 140 * @param repeat_delay_ms Delay before key auto-repeat starts (in ms) 141 * @param repeat_rate_ms Delay between successive key repeats (in ms) 142 */ 143 void input_set_delays(struct input_config *config, int repeat_delay_ms, 144 int repeat_rate_ms); 145 146 /** 147 * Tell the input layer whether to allow the caller to determine repeats 148 * 149 * Generally the input library handles processing of a list of scanned keys. 150 * Repeated keys need to be generated based on a timer in this case, since all 151 * that is provided is a list of keys current depressed. 152 * 153 * Keyboards which do their own scanning will resend codes when they want to 154 * inject a repeating key. This function can be called at start-up to select 155 * this behaviour. 156 * 157 * @param config Input state 158 * @param allow_repeats true to repeat depressed keys every time 159 * input_send_keycodes() is called, false to do normal 160 * keyboard repeat processing with a timer. 161 */ 162 void input_allow_repeats(struct input_config *config, bool allow_repeats); 163 164 /** 165 * Check if keyboard LEDs need to be updated 166 * 167 * This can be called after input_tstc() to see if keyboard LEDs need 168 * updating. 169 * 170 * @param config Input state 171 * @return -1 if no LEDs need updating, other value if they do 172 */ 173 int input_leds_changed(struct input_config *config); 174 175 /** 176 * Set up the key map tables 177 * 178 * This must be called after input_init() or keycode decoding will not work. 179 * 180 * @param config Input state 181 * @param german true to use German keyboard layout, false for US 182 * @return 0 if ok, -1 on error 183 */ 184 int input_add_tables(struct input_config *config, bool german); 185 186 /** 187 * Set up the input handler with basic key maps. 188 * 189 * @param config Input state 190 * @param leds Initial LED value (INPUT_LED_ mask), 0 suggested 191 * @return 0 if ok, -1 on error 192 */ 193 int input_init(struct input_config *config, int leds); 194 195 #ifdef CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 196 extern int overwrite_console(void); 197 #define OVERWRITE_CONSOLE overwrite_console() 198 #else 199 #define OVERWRITE_CONSOLE 0 200 #endif /* CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE */ 201 202 #endif 203