nodemcu-firmware/components/modules/matrix.c

517 lines
13 KiB
C

/*
* Module for interfacing with cheap matrix keyboards like telephone keypads
*
* The idea is to have pullups on all the rows, and drive the columns low.
* WHen a key is pressed, one of the rows will go low and trigger an interrupt. Disable
* all the row interrupts.
* Then we disable all the columns and then drive each column low in turn. Hopefully
* one of the rows will go low. This is a keypress. We only report the first keypress found.
* we start a timer to handle debounce.
* On timer expiry, see if any key is pressed, if so, just wait agin (maybe should use interrupts)
* If no key is pressed, run timer again. On timer expiry, re-enable interrupts.
*
* Philip Gladstone, N1DQ
*/
#include "module.h"
#include "lauxlib.h"
#include "platform.h"
#include "task/task.h"
#include "esp_timer.h"
#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include "driver/gpio.h"
#define M_DEBUG printf
#define MATRIX_PRESS_INDEX 0
#define MATRIX_RELEASE_INDEX 1
#define MASK(x) (1 << MATRIX_##x##_INDEX)
#define MATRIX_ALL 0x3
#define CALLBACK_COUNT 2
#define QUEUE_SIZE 8
typedef struct {
int32_t character; // 1 + character for press, -1 - character for release
uint32_t time_us;
} matrix_event_t;
typedef struct {
uint8_t column_count;
uint8_t row_count;
uint8_t *columns;
uint8_t *rows;
bool waiting_for_release;
bool open;
int character_ref;
int callback[CALLBACK_COUNT];
esp_timer_handle_t timer_handle;
int8_t task_queued;
uint32_t read_offset; // Accessed by task
uint32_t write_offset; // Accessed by ISR
uint8_t last_character;
matrix_event_t queue[QUEUE_SIZE];
void *callback_arg;
} DATA;
static task_handle_t tasknumber;
static void lmatrix_timer_done(void *param);
//
// Queue is empty if read == write.
// However, we always want to keep the previous value
// so writing is only allowed if write - read < QUEUE_SIZE - 1
#define GET_LAST_STATUS(d) (d->queue[(d->write_offset - 1) & (QUEUE_SIZE - 1)])
#define GET_PREV_STATUS(d) (d->queue[(d->write_offset - 2) & (QUEUE_SIZE - 1)])
#define HAS_QUEUED_DATA(d) (d->read_offset < d->write_offset)
#define HAS_QUEUE_SPACE(d) (d->read_offset + QUEUE_SIZE - 1 > d->write_offset)
#define REPLACE_IT(d, x) \
(d->queue[(d->write_offset - 1) & (QUEUE_SIZE - 1)] = \
(matrix_event_t){(x), esp_timer_get_time()})
#define QUEUE_IT(d, x) \
(d->queue[(d->write_offset++) & (QUEUE_SIZE - 1)] = \
(matrix_event_t){(x), esp_timer_get_time()})
#define GET_READ_STATUS(d) (d->queue[d->read_offset & (QUEUE_SIZE - 1)])
#define ADVANCE_IF_POSSIBLE(d) \
if (d->read_offset < d->write_offset) { \
d->read_offset++; \
}
static void set_gpio_mode_input(int pin, gpio_int_type_t intr) {
gpio_config_t config = {.pin_bit_mask = 1LL << pin,
.mode = GPIO_MODE_INPUT,
.pull_up_en = GPIO_PULLUP_ENABLE,
.pull_down_en = GPIO_PULLDOWN_DISABLE,
.intr_type = intr};
gpio_config(&config);
}
static void set_gpio_mode_output(int pin) {
gpio_config_t config = {.pin_bit_mask = 1LL << pin,
.mode = GPIO_MODE_OUTPUT_OD,
.pull_up_en = GPIO_PULLUP_DISABLE,
.pull_down_en = GPIO_PULLDOWN_DISABLE
};
gpio_config(&config);
}
static void set_columns(DATA *d, int level) {
for (int i = 0; i < d->column_count; i++) {
gpio_set_level(d->columns[i], level);
}
}
static void initialize_pins(DATA *d) {
for (int i = 0; i < d->column_count; i++) {
set_gpio_mode_output(d->columns[i]);
}
set_columns(d, 0);
for (int i = 0; i < d->row_count; i++) {
set_gpio_mode_input(d->rows[i], d->waiting_for_release ? GPIO_INTR_POSEDGE
: GPIO_INTR_NEGEDGE);
}
}
static void disable_row_interrupts(DATA *d) {
for (int i = 0; i < d->row_count; i++) {
gpio_set_intr_type(d->rows[i], GPIO_INTR_DISABLE);
}
}
// Just takes the channel number. Cleans up the resources used.
int matrix_close(DATA *d) {
if (!d) {
return 0;
}
disable_row_interrupts(d);
for (int i = 0; i < d->row_count; i++) {
gpio_isr_handler_remove(d->rows[i]);
}
for (int i = 0; i < d->column_count; i++) {
set_gpio_mode_input(d->columns[i], GPIO_INTR_DISABLE);
}
return 0;
}
// Character returned is 0 .. max if pressed. -1 if not.
static int matrix_get_character(DATA *d, bool trace)
{
set_columns(d, 1);
disable_row_interrupts(d);
int character = -1;
// We are either waiting for a negative edge (keypress) or a positive edge
// (keyrelease)
//M_DEBUG("matrix_get_character called\n");
for (int i = 0; i < d->column_count && character < 0; i++) {
gpio_set_level(d->columns[i], 0);
for (int j = 0; j < d->row_count && character < 0; j++) {
if (gpio_get_level(d->rows[j]) == 0) {
if (trace) {
M_DEBUG("Found keypress at %d %d\n", i, j);
}
// We found a keypress
character = j * d->column_count + i;
}
}
gpio_set_level(d->columns[i], 1);
}
//M_DEBUG("returning %d\n", character);
return character;
}
static void matrix_queue_character(DATA *d, int character)
{
// If character is >= 0 then we have found the character -- so send it.
// M_DEBUG("Skipping queuing\n");
if (d->waiting_for_release == (character < 0)) {
if (character >= 0) {
character++;
d->last_character = character;
} else {
character = -d->last_character;
}
if (HAS_QUEUE_SPACE(d)) {
QUEUE_IT(d, character);
if (!d->task_queued) {
if (task_post_medium(tasknumber, (task_param_t)d)) {
d->task_queued = 1;
}
}
}
}
}
static void matrix_interrupt(void *arg) {
// This function runs with high priority
DATA *d = (DATA *)arg;
int character = matrix_get_character(d, false);
matrix_queue_character(d, character);
d->waiting_for_release = character >= 0;
esp_timer_start_once(d->timer_handle, 5000);
}
bool matrix_has_queued_event(DATA *d) {
if (!d) {
return false;
}
return HAS_QUEUED_DATA(d);
}
// Get the oldest event in the queue and remove it (if possible)
static bool matrix_getevent(DATA *d, matrix_event_t *resultp) {
matrix_event_t result = {0};
if (!d) {
return false;
}
bool status = false;
if (HAS_QUEUED_DATA(d)) {
result = GET_READ_STATUS(d);
d->read_offset++;
status = true;
} else {
result = GET_LAST_STATUS(d);
}
*resultp = result;
return status;
}
static void callback_free_one(lua_State *L, int *cb_ptr)
{
if (*cb_ptr != LUA_NOREF) {
luaL_unref(L, LUA_REGISTRYINDEX, *cb_ptr);
*cb_ptr = LUA_NOREF;
}
}
static void callback_free(lua_State* L, DATA *d, int mask)
{
if (d) {
int i;
for (i = 0; i < CALLBACK_COUNT; i++) {
if (mask & (1 << i)) {
callback_free_one(L, &d->callback[i]);
}
}
}
}
static int callback_setOne(lua_State* L, int *cb_ptr, int arg_number)
{
if (lua_isfunction(L, arg_number)) {
lua_pushvalue(L, arg_number); // copy argument (func) to the top of stack
callback_free_one(L, cb_ptr);
*cb_ptr = luaL_ref(L, LUA_REGISTRYINDEX);
return 0;
}
return -1;
}
static int callback_set(lua_State* L, DATA *d, int mask, int arg_number)
{
int result = 0;
int i;
for (i = 0; i < CALLBACK_COUNT; i++) {
if (mask & (1 << i)) {
result |= callback_setOne(L, &d->callback[i], arg_number);
}
}
return result;
}
static void callback_callOne(lua_State* L, int cb, int mask, int arg, uint32_t time)
{
if (cb != LUA_NOREF) {
lua_rawgeti(L, LUA_REGISTRYINDEX, cb);
lua_pushinteger(L, mask);
lua_pushvalue(L, arg - 2);
lua_pushinteger(L, time);
luaL_pcallx(L, 3, 0);
}
}
static void callback_call(lua_State* L, DATA *d, int cbnum, int key, uint32_t time)
{
if (d) {
lua_rawgeti(L, LUA_REGISTRYINDEX, d->character_ref);
lua_rawgeti(L, -1, key);
callback_callOne(L, d->callback[cbnum], 1 << cbnum, -1, time);
lua_pop(L, 2);
}
}
static void getpins(lua_State *L, int argno, int count, uint8_t *dest)
{
for (int i = 1; i <= count; i++) {
lua_rawgeti(L, argno, i);
*dest++ = lua_tonumber(L, -1);
lua_pop(L, 1);
}
}
// Lua: setup({cols}, {rows}, {characters})
static int lmatrix_setup( lua_State* L )
{
// Get the sizes of the first two tables
luaL_checktype(L, 1, LUA_TTABLE);
luaL_checktype(L, 2, LUA_TTABLE);
luaL_checktype(L, 3, LUA_TTABLE);
size_t columns = lua_rawlen(L, 1);
size_t rows = lua_rawlen(L, 2);
if (columns > 255 || rows > 255) {
return luaL_error(L, "Too many rows or columns");
}
DATA *d = (DATA *)lua_newuserdata(L, sizeof(DATA) + rows + columns);
if (!d) return luaL_error(L, "not enough memory");
memset(d, 0, sizeof(*d) + rows + columns);
luaL_getmetatable(L, "matrix.keyboard");
lua_setmetatable(L, -2);
d->columns = (uint8_t *) (d + 1);
d->rows = d->columns + columns;
d->column_count = columns;
d->row_count = rows;
esp_timer_create_args_t timer_args = {
.callback = lmatrix_timer_done,
.dispatch_method = ESP_TIMER_TASK,
.name = "matrix_timer",
.arg = d
};
esp_timer_create(&timer_args, &d->timer_handle);
for (int i = 0; i < CALLBACK_COUNT; i++) {
d->callback[i] = LUA_NOREF;
}
getpins(L, 1, columns, d->columns);
getpins(L, 2, rows, d->rows);
lua_pushvalue(L, 3);
d->character_ref = luaL_ref(L, LUA_REGISTRYINDEX);
d->open = true;
for (int i = 0; i < d->row_count; i++) {
gpio_isr_handler_add(d->rows[i], matrix_interrupt, d);
}
initialize_pins(d);
return 1;
}
// Lua: close( )
static int lmatrix_close( lua_State* L )
{
DATA *d = (DATA *)luaL_checkudata(L, 1, "matrix.keyboard");
if (d->open) {
callback_free(L, d, MATRIX_ALL);
if (matrix_close( d )) {
return luaL_error( L, "Unable to close switch." );
}
esp_timer_stop(d->timer_handle);
esp_timer_delete(d->timer_handle);
luaL_unref(L, LUA_REGISTRYINDEX, d->character_ref);
d->open = false;
}
return 0;
}
// Lua: on( mask[, cb] )
static int lmatrix_on( lua_State* L )
{
DATA *d = (DATA *)luaL_checkudata(L, 1, "matrix.keyboard");
int mask = luaL_checkinteger(L, 2);
if (lua_gettop(L) >= 3) {
if (callback_set(L, d, mask, 3)) {
return luaL_error( L, "Unable to set callback." );
}
} else {
callback_free(L, d, mask);
}
return 0;
}
// Returns TRUE if there maybe/is more stuff to do
static bool lmatrix_dequeue_single(lua_State* L, DATA *d)
{
bool something_pending = false;
if (d) {
matrix_event_t result;
if (matrix_getevent(d, &result)) {
int character = result.character;
callback_call(L, d, character > 0 ? MATRIX_PRESS_INDEX : MATRIX_RELEASE_INDEX, character < 0 ? -character : character, result.time_us);
d->task_queued = 0;
something_pending = matrix_has_queued_event(d);
}
}
return something_pending;
}
static void lmatrix_timer_done(void *param)
{
DATA *d = (DATA *) param;
// We need to see if the key is still pressed, and if so, enable rising edge interrupts
int character = matrix_get_character(d, true);
M_DEBUG("Timer fired with character %d (waiting for release %d)\n", character, d->waiting_for_release);
matrix_queue_character(d, character);
d->waiting_for_release = (character >= 0);
M_DEBUG("Timer: Waiting for release is %d\n", d->waiting_for_release);
for (int i = 0; i < d->row_count; i++) {
gpio_set_intr_type(d->rows[i], d->waiting_for_release ? GPIO_INTR_POSEDGE
: GPIO_INTR_NEGEDGE);
}
set_columns(d, 0);
}
static void lmatrix_task(task_param_t param, task_prio_t prio)
{
(void) prio;
M_DEBUG("Task invoked\n");
bool need_to_post = false;
lua_State *L = lua_getstate();
DATA *d = (DATA *) param;
if (d) {
if (lmatrix_dequeue_single(L, d)) {
need_to_post = true;
}
}
if (need_to_post) {
// If there is pending stuff, queue another task
task_post_medium(tasknumber, param);
}
M_DEBUG("Task done\n");
}
// Module function map
LROT_BEGIN(matrix, NULL, 0)
LROT_FUNCENTRY( setup, lmatrix_setup )
LROT_NUMENTRY( PRESS, MASK(PRESS) )
LROT_NUMENTRY( RELEASE, MASK(RELEASE) )
LROT_NUMENTRY( ALL, MATRIX_ALL )
LROT_END(matrix, NULL, 0)
// Module function map
LROT_BEGIN(matrix_keyboard, NULL, LROT_MASK_GC_INDEX)
LROT_FUNCENTRY(__gc, lmatrix_close)
LROT_TABENTRY(__index, matrix_keyboard)
LROT_FUNCENTRY(on, lmatrix_on)
LROT_FUNCENTRY(close, lmatrix_close)
LROT_END(matrix_keyboard, NULL, LROT_MASK_GC_INDEX)
static int matrix_open(lua_State *L) {
luaL_rometatable(L, "matrix.keyboard",
LROT_TABLEREF(matrix_keyboard)); // create metatable
tasknumber = task_get_id(lmatrix_task);
return 0;
}
NODEMCU_MODULE(MATRIX, "matrix", matrix, matrix_open);