2 files changed, 208 insertions(+), 0 deletions(-)

A image-viewer/include/input.h
A image-viewer/src/input.c

@@ 0,0 1,57 @@
+#include <stdint.h>
+#include <stdbool.h>
+#include <time.h>
+
+#define ROTATION_ENCODERS_COUNT 3
+
+typedef void (*command_fun)(void *state, int delta);
+
+typedef enum {
+  IN_KEYBOARD,
+  IN_ENCODER_ROTATE,
+  IN_ENCODER_CLICK,
+} input_type_t;
+
+typedef struct {
+  input_type_t type;
+  char filter;
+} input_t;
+
+typedef struct {
+  uint8_t absolute;
+  int8_t delta;
+
+  bool button;
+  bool button_prev;
+
+  time_t pressed_time;
+} rotation_encoder_state_t;
+
+typedef struct {
+  void* base_address;
+  rotation_encoder_state_t encoders_state[ROTATION_ENCODERS_COUNT];
+} rotation_encoders_t;
+
+typedef struct {
+  command_fun cmd;
+  input_t input;
+  void *state;
+} command_t;
+
+typedef struct {
+  command_t *commands;
+  uint8_t count;
+  uint8_t size;
+
+  rotation_encoders_t encoders;
+} commands_t;
+
+commands_t commands_create(command_t *array, uint8_t size,
+                           void *reg_knobs_base);
+
+bool commands_register(commands_t *commands, input_type_t type,
+                       char filter, command_fun fun, void *state);
+
+bool commands_unregister(commands_t *commands, command_t *command);
+
+short commands_check_input(commands_t *commands);

@@ 0,0 1,151 @@
+#include "input.h"
+#include "nonblocking_io.h"
+#include <stdint.h>
+#include <time.h>
+#include <unistd.h>
+
+#define ROTATION_DELTA 0
+#define ENCODERS_MAX 255
+#define DEBOUNCE_TIME 0.2 // seconds
+
+void commands_update_rotation_encoders(rotation_encoders_t *commands);
+
+void commands_rotation_encoders_init(commands_t *commands) {
+  for (int i = 0; i < ROTATION_ENCODERS_COUNT; i++) {
+    rotation_encoder_state_t state = {
+      .absolute = 0,
+      .delta = 0,
+    };
+    commands->encoders.encoders_state[i] = state;
+  }
+
+  commands_update_rotation_encoders(&commands->encoders);
+}
+
+commands_t commands_create(command_t *array, uint8_t size, void *reg_knobs_base) {
+  commands_t commands = {
+    .size = size,
+    .count = 0,
+    .commands = array,
+    .encoders = {
+      .base_address = reg_knobs_base
+    }
+  };
+
+  commands_rotation_encoders_init(&commands);
+
+  return commands;
+}
+
+bool commands_register(commands_t * commands, input_type_t type, char filter,
+                        command_fun fun, void *state) {
+  if (commands->count >= commands->size) {
+    return false;
+  }
+
+  command_t command = {
+      .state = state,
+      .cmd = fun,
+      .input = {.filter = filter, .type = type},
+  };
+
+  commands->commands[commands->size++] = command;
+  return true;
+}
+
+bool commands_unregister(commands_t * commands, command_t * command) {
+  int found = -1;
+  for (int i = 0; i < commands->count; i++) {
+    if (&commands->commands[i] == command) {
+      found = i;
+    }
+  }
+
+  if (found == -1) {
+    return false;
+  }
+
+  for (int i = found; i < commands->count - 1; i++) {
+    commands->commands[i] = commands->commands[i + 1];
+  }
+  commands->count--;
+
+  return true;
+}
+
+int16_t commands_execute(commands_t * commands, input_type_t type, char filter,
+                        int amount) {
+  int16_t commands_executed = 0;
+  for (int i = 0; i < commands->size; i++) {
+    command_t command = commands->commands[i];
+
+    if (command.input.filter == filter && command.input.type == type) {
+      command.cmd(command.state, amount);
+      commands_executed++;
+    }
+  }
+
+  return commands_executed;
+}
+
+void commands_update_rotation_encoders(rotation_encoders_t *encoders) {
+  uint8_t btns = *(volatile uint8_t*)(encoders->base_address + ROTATION_ENCODERS_COUNT);
+
+  for (int i = 0; i < ROTATION_ENCODERS_COUNT; i++) {
+    rotation_encoder_state_t state = encoders->encoders_state[i];
+    uint8_t rotation = *(volatile uint8_t*)(encoders->base_address + i);
+    bool btn = (btns >> (7 - i)) & 1;
+
+    uint8_t diff = rotation - state.absolute;
+
+    state.delta = (int8_t)diff;
+    state.absolute = rotation;
+
+    time_t now = time(NULL);
+    if (btn && !state.button) {
+      state.button = true;
+      state.button_prev = false;
+      state.pressed_time = time(NULL);
+
+    } else if (!btn && state.button &&
+               difftime(now, state.pressed_time) > DEBOUNCE_TIME) {
+      state.button = false;
+      state.button_prev = true;
+    }
+
+    encoders->encoders_state[i] = state;
+  }
+}
+
+int16_t commands_check_input(commands_t * commands) {
+  int16_t commands_executed = 0;
+
+  uint8_t data;
+  int read;
+  while ((read = file_read_nonblocking(STDIN_FILENO, 1, &data)) > 0) {
+    commands_executed += commands_execute(commands, IN_KEYBOARD, data, 5);
+  }
+
+  if (read < 0) {
+    return -1;
+  }
+
+  rotation_encoders_t encoders = commands->encoders;
+  commands_update_rotation_encoders(&encoders);
+  for (int i = 0; i < commands->size; i++) {
+    command_t command = commands->commands[i];
+    input_t input = command.input;
+    rotation_encoder_state_t state = encoders.encoders_state[(uint8_t)command.input.filter];
+
+    bool button_changed = state.button_prev != state.button;
+    bool rotation_changed = state.delta != 0;
+
+    if (input.type == IN_ENCODER_ROTATE && rotation_changed) {
+      command.cmd(command.state, state.delta);
+    } else if (input.type == IN_ENCODER_CLICK && button_changed) {
+      command.cmd(command.state, state.button);
+    }
+  }
+
+  return commands_executed;
+}