1 /* 2 * Keyboard input helper functions (too small to be called a layer) 3 * 4 * Copyright (c) 2011 The Chromium OS Authors. 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #ifndef _INPUT_H 10 #define _INPUT_H 11 12 enum { 13 INPUT_MAX_MODIFIERS = 4, 14 INPUT_BUFFER_LEN = 16, 15 }; 16 17 enum { 18 /* Keyboard LEDs */ 19 INPUT_LED_SCROLL = 1 << 0, 20 INPUT_LED_CAPS = 1 << 1, 21 INPUT_LED_NUM = 1 << 2, 22 }; 23 24 /* 25 * This table translates key codes to ASCII. Most of the entries are ASCII 26 * codes, but entries after KEY_FIRST_MOD indicate that this key is a 27 * modifier key, like shift, ctrl. KEY_FIRST_MOD + MOD_SHIFT is the shift 28 * key, for example. 29 */ 30 struct input_key_xlate { 31 /* keycode of the modifiers which select this table, -1 if none */ 32 int left_keycode; 33 int right_keycode; 34 const uchar *xlate; /* keycode to ASCII table */ 35 int num_entries; /* number of entries in this table */ 36 }; 37 38 struct input_config { 39 struct udevice *dev; 40 uchar fifo[INPUT_BUFFER_LEN]; 41 int fifo_in, fifo_out; 42 43 /* Which modifiers are active (1 bit for each MOD_... value) */ 44 uchar modifiers; 45 uchar flags; /* active state keys (FLAGS_...) */ 46 uchar leds; /* active LEDs (INPUT_LED_...) */ 47 uchar leds_changed; /* LEDs that just changed */ 48 uchar num_tables; /* number of modifier tables */ 49 int prev_keycodes[INPUT_BUFFER_LEN]; /* keys held last time */ 50 int num_prev_keycodes; /* number of prev keys */ 51 struct input_key_xlate table[INPUT_MAX_MODIFIERS]; 52 53 /** 54 * Function the input helper calls to scan the keyboard 55 * 56 * @param config Input state 57 * @return 0 if no keys read, otherwise number of keys read, or 1 if 58 * unknown 59 */ 60 int (*read_keys)(struct input_config *config); 61 bool allow_repeats; /* Don't filter out repeats */ 62 unsigned int next_repeat_ms; /* Next time we repeat a key */ 63 unsigned int repeat_delay_ms; /* Time before autorepeat starts */ 64 unsigned int repeat_rate_ms; /* Autorepeat rate in ms */ 65 }; 66 67 struct stdio_dev; 68 69 /** 70 * Convert a list of key codes into ASCII and send them 71 * 72 * @param config Input state 73 * @param keycode List of key codes to examine 74 * @param num_keycodes Number of key codes 75 * @return number of ascii characters sent, or 0 if none, or -1 for an 76 * internal error 77 */ 78 int input_send_keycodes(struct input_config *config, int keycode[], int count); 79 80 /** 81 * Add a new keycode to an existing list of keycodes 82 * 83 * This can be used to handle keyboards which do their own scanning. An 84 * internal list of depressed keys is maintained by the input library. Then 85 * this function is called to add a new key to the list (when a 'make code' is 86 * received), or remove a key (when a 'break code' is received). 87 * 88 * This function looks after maintenance of the list of active keys, and calls 89 * input_send_keycodes() with its updated list. 90 * 91 * @param config Input state 92 * @param new_keycode New keycode to add/remove 93 * @param release true if this key was released, false if depressed 94 * @return number of ascii characters sent, or 0 if none, or -1 for an 95 * internal error 96 */ 97 int input_add_keycode(struct input_config *config, int new_keycode, 98 bool release); 99 100 /** 101 * Add a new key translation table to the input 102 * 103 * @param config Input state 104 * @param left_keycode Key to hold to get into this table 105 * @param right_keycode Another key to hold to get into this table 106 * @param xlate Conversion table from key codes to ASCII 107 * @param num_entries Number of entries in xlate table 108 */ 109 int input_add_table(struct input_config *config, int left_keycode, 110 int right_keycode, const uchar *xlate, int num_entries); 111 112 /** 113 * Test if keys are available to be read 114 * 115 * @param config Input state 116 * @return 0 if no keys available, 1 if keys are available 117 */ 118 int input_tstc(struct input_config *config); 119 120 /** 121 * Read a key 122 * 123 * TODO: U-Boot wants 0 for no key, but Ctrl-@ is a valid key... 124 * 125 * @param config Input state 126 * @return key, or 0 if no key, or -1 if error 127 */ 128 int input_getc(struct input_config *config); 129 130 /** 131 * Register a new device with stdio and switch to it if wanted 132 * 133 * @param dev Pointer to device 134 * @return 0 if ok, -1 on error 135 */ 136 int input_stdio_register(struct stdio_dev *dev); 137 138 /** 139 * Set up the keyboard autorepeat delays 140 * 141 * @param repeat_delay_ms Delay before key auto-repeat starts (in ms) 142 * @param repeat_rate_ms Delay between successive key repeats (in ms) 143 */ 144 void input_set_delays(struct input_config *config, int repeat_delay_ms, 145 int repeat_rate_ms); 146 147 /** 148 * Tell the input layer whether to allow the caller to determine repeats 149 * 150 * Generally the input library handles processing of a list of scanned keys. 151 * Repeated keys need to be generated based on a timer in this case, since all 152 * that is provided is a list of keys current depressed. 153 * 154 * Keyboards which do their own scanning will resend codes when they want to 155 * inject a repeating key. This function can be called at start-up to select 156 * this behaviour. 157 * 158 * @param config Input state 159 * @param allow_repeats true to repeat depressed keys every time 160 * input_send_keycodes() is called, false to do normal 161 * keyboard repeat processing with a timer. 162 */ 163 void input_allow_repeats(struct input_config *config, bool allow_repeats); 164 165 /** 166 * Check if keyboard LEDs need to be updated 167 * 168 * This can be called after input_tstc() to see if keyboard LEDs need 169 * updating. 170 * 171 * @param config Input state 172 * @return -1 if no LEDs need updating, other value if they do 173 */ 174 int input_leds_changed(struct input_config *config); 175 176 /** 177 * Set up the key map tables 178 * 179 * This must be called after input_init() or keycode decoding will not work. 180 * 181 * @param config Input state 182 * @param german true to use German keyboard layout, false for US 183 * @return 0 if ok, -1 on error 184 */ 185 int input_add_tables(struct input_config *config, bool german); 186 187 /** 188 * Set up the input handler with basic key maps. 189 * 190 * @param config Input state 191 * @param leds Initial LED value (INPUT_LED_ mask), 0 suggested 192 * @return 0 if ok, -1 on error 193 */ 194 int input_init(struct input_config *config, int leds); 195 196 #ifdef CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 197 extern int overwrite_console(void); 198 #define OVERWRITE_CONSOLE overwrite_console() 199 #else 200 #define OVERWRITE_CONSOLE 0 201 #endif /* CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE */ 202 203 #endif 204