/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Keyboard input helper functions (too small to be called a layer)
*
* Copyright (c) 2011 The Chromium OS Authors.
*/
#ifndef _INPUT_H
#define _INPUT_H
enum {
INPUT_MAX_MODIFIERS = 4,
INPUT_BUFFER_LEN = 16,
};
enum {
/* Keyboard LEDs */
INPUT_LED_SCROLL = 1 << 0,
INPUT_LED_NUM = 1 << 1,
INPUT_LED_CAPS = 1 << 2,
};
/*
* This table translates key codes to ASCII. Most of the entries are ASCII
* codes, but entries after KEY_FIRST_MOD indicate that this key is a
* modifier key, like shift, ctrl. KEY_FIRST_MOD + MOD_SHIFT is the shift
* key, for example.
*/
struct input_key_xlate {
/* keycode of the modifiers which select this table, -1 if none */
int left_keycode;
int right_keycode;
const uchar *xlate; /* keycode to ASCII table */
int num_entries; /* number of entries in this table */
};
struct input_config {
struct udevice *dev;
uchar fifo[INPUT_BUFFER_LEN];
int fifo_in, fifo_out;
/* Which modifiers are active (1 bit for each MOD_... value) */
uchar modifiers;
uchar flags; /* active state keys (FLAGS_...) */
uchar leds; /* active LEDs (INPUT_LED_...) */
uchar leds_changed; /* LEDs that just changed */
uchar num_tables; /* number of modifier tables */
int prev_keycodes[INPUT_BUFFER_LEN]; /* keys held last time */
int num_prev_keycodes; /* number of prev keys */
struct input_key_xlate table[INPUT_MAX_MODIFIERS];
/**
* Function the input helper calls to scan the keyboard
*
* @param config Input state
* @return 0 if no keys read, otherwise number of keys read, or 1 if
* unknown
*/
int (*read_keys)(struct input_config *config);
bool allow_repeats; /* Don't filter out repeats */
unsigned int next_repeat_ms; /* Next time we repeat a key */
unsigned int repeat_delay_ms; /* Time before autorepeat starts */
unsigned int repeat_rate_ms; /* Autorepeat rate in ms */
};
struct stdio_dev;
/**
* Convert a list of key codes into ASCII and send them
*
* @param config Input state
* @param keycode List of key codes to examine
* @param num_keycodes Number of key codes
* @return number of ascii characters sent, or 0 if none, or -1 for an
* internal error
*/
int input_send_keycodes(struct input_config *config, int keycode[], int count);
/**
* Add a new keycode to an existing list of keycodes
*
* This can be used to handle keyboards which do their own scanning. An
* internal list of depressed keys is maintained by the input library. Then
* this function is called to add a new key to the list (when a 'make code' is
* received), or remove a key (when a 'break code' is received).
*
* This function looks after maintenance of the list of active keys, and calls
* input_send_keycodes() with its updated list.
*
* @param config Input state
* @param new_keycode New keycode to add/remove
* @param release true if this key was released, false if depressed
* @return number of ascii characters sent, or 0 if none, or -1 for an
* internal error
*/
int input_add_keycode(struct input_config *config, int new_keycode,
bool release);
/**
* Add a new key translation table to the input
*
* @param config Input state
* @param left_keycode Key to hold to get into this table
* @param right_keycode Another key to hold to get into this table
* @param xlate Conversion table from key codes to ASCII
* @param num_entries Number of entries in xlate table
*/
int input_add_table(struct input_config *config, int left_keycode,
int right_keycode, const uchar *xlate, int num_entries);
/**
* Test if keys are available to be read
*
* @param config Input state
* @return 0 if no keys available, 1 if keys are available
*/
int input_tstc(struct input_config *config);
/**
* Read a key
*
* TODO: U-Boot wants 0 for no key, but Ctrl-@ is a valid key...
*
* @param config Input state
* @return key, or 0 if no key, or -1 if error
*/
int input_getc(struct input_config *config);
/**
* Register a new device with stdio and switch to it if wanted
*
* @param dev Pointer to device
* @return 0 if ok, -1 on error
*/
int input_stdio_register(struct stdio_dev *dev);
/**
* Set up the keyboard autorepeat delays
*
* @param repeat_delay_ms Delay before key auto-repeat starts (in ms)
* @param repeat_rate_ms Delay between successive key repeats (in ms)
*/
void input_set_delays(struct input_config *config, int repeat_delay_ms,
int repeat_rate_ms);
/**
* Tell the input layer whether to allow the caller to determine repeats
*
* Generally the input library handles processing of a list of scanned keys.
* Repeated keys need to be generated based on a timer in this case, since all
* that is provided is a list of keys current depressed.
*
* Keyboards which do their own scanning will resend codes when they want to
* inject a repeating key. This function can be called at start-up to select
* this behaviour.
*
* @param config Input state
* @param allow_repeats true to repeat depressed keys every time
* input_send_keycodes() is called, false to do normal
* keyboard repeat processing with a timer.
*/
void input_allow_repeats(struct input_config *config, bool allow_repeats);
/**
* Check if keyboard LEDs need to be updated
*
* This can be called after input_tstc() to see if keyboard LEDs need
* updating.
*
* @param config Input state
* @return -1 if no LEDs need updating, other value if they do
*/
int input_leds_changed(struct input_config *config);
/**
* Set up the key map tables
*
* This must be called after input_init() or keycode decoding will not work.
*
* @param config Input state
* @param german true to use German keyboard layout, false for US
* @return 0 if ok, -1 on error
*/
int input_add_tables(struct input_config *config, bool german);
/**
* Set up the input handler with basic key maps.
*
* @param config Input state
* @param leds Initial LED value (INPUT_LED_ mask), 0 suggested
* @return 0 if ok, -1 on error
*/
int input_init(struct input_config *config, int leds);
#ifdef CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
extern int overwrite_console(void);
#define OVERWRITE_CONSOLE overwrite_console()
#else
#define OVERWRITE_CONSOLE 0
#endif /* CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE */
#endif