include/input.h

   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         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 num_tables;       /* number of modifier tables */
  47         int prev_keycodes[INPUT_BUFFER_LEN];    /* keys held last time */
  48         int num_prev_keycodes;  /* number of prev keys */
  49         struct input_key_xlate table[INPUT_MAX_MODIFIERS];
  50
  51         /**
  52          * Function the input helper calls to scan the keyboard
  53          *
  54          * @param config        Input state
  55          * @return 0 if no keys read, otherwise number of keys read, or 1 if
  56          *              unknown
  57          */
  58         int (*read_keys)(struct input_config *config);
  59         unsigned int next_repeat_ms;    /* Next time we repeat a key */
  60         unsigned int repeat_delay_ms;   /* Time before autorepeat starts */
  61         unsigned int repeat_rate_ms;    /* Autorepeat rate in ms */
  62 };
  63
  64 struct stdio_dev;
  65
  66 /**
  67  * Convert a list of key codes into ASCII and send them
  68  *
  69  * @param config        Input state
  70  * @param keycode       List of key codes to examine
  71  * @param num_keycodes  Number of key codes
  72  * @return number of ascii characters sent, or 0 if none, or -1 for an
  73  *      internal error
  74  */
  75 int input_send_keycodes(struct input_config *config, int keycode[], int count);
  76
  77 /**
  78  * Add a new key translation table to the input
  79  *
  80  * @param config        Input state
  81  * @param left_keycode  Key to hold to get into this table
  82  * @param right_keycode Another key to hold to get into this table
  83  * @param xlate         Conversion table from key codes to ASCII
  84  * @param num_entries   Number of entries in xlate table
  85  */
  86 int input_add_table(struct input_config *config, int left_keycode,
  87                     int right_keycode, const uchar *xlate, int num_entries);
  88
  89 /**
  90  * Test if keys are available to be read
  91  *
  92  * @param config        Input state
  93  * @return 0 if no keys available, 1 if keys are available
  94  */
  95 int input_tstc(struct input_config *config);
  96
  97 /**
  98  * Read a key
  99  *
 100  * TODO: U-Boot wants 0 for no key, but Ctrl-@ is a valid key...
 101  *
 102  * @param config        Input state
 103  * @return key, or 0 if no key, or -1 if error
 104  */
 105 int input_getc(struct input_config *config);
 106
 107 /**
 108  * Register a new device with stdio and switch to it if wanted
 109  *
 110  * @param dev   Pointer to device
 111  * @return 0 if ok, -1 on error
 112  */
 113 int input_stdio_register(struct stdio_dev *dev);
 114
 115 /**
 116  * Set up the keyboard autorepeat delays
 117  *
 118  * @param repeat_delay_ms       Delay before key auto-repeat starts (in ms)
 119  * @param repeat_rate_ms        Delay between successive key repeats (in ms)
 120  */
 121 void input_set_delays(struct input_config *config, int repeat_delay_ms,
 122                int repeat_rate_ms);
 123
 124 /**
 125  * Set up the input handler with basic key maps.
 126  *
 127  * @param config        Input state
 128  * @param leds          Initial LED value (INPUT_LED_ mask), 0 suggested
 129  * @return 0 if ok, -1 on error
 130  */
 131 int input_init(struct input_config *config, int leds);
 132
 133 #ifdef CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
 134 extern int overwrite_console(void);
 135 #define OVERWRITE_CONSOLE overwrite_console()
 136 #else
 137 #define OVERWRITE_CONSOLE 0
 138 #endif /* CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE */
 139
 140 #endif