pebble/src/fw/drivers/button.c
2025-01-27 11:38:16 -08:00

114 lines
3.3 KiB
C

/*
* Copyright 2024 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "drivers/button.h"
#include "board/board.h"
#include "console/prompt.h"
#include "drivers/periph_config.h"
#include "drivers/gpio.h"
static void initialize_button_common(void) {
if (!BOARD_CONFIG_BUTTON.button_com.gpio) {
// This board doesn't use a button common pin.
return;
}
// Configure BUTTON_COM to drive low. When the button
// is pressed this pin will be connected to the pin for the
// button.
gpio_use(BOARD_CONFIG_BUTTON.button_com.gpio);
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_StructInit(&GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = BOARD_CONFIG_BUTTON.button_com.gpio_pin;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(BOARD_CONFIG_BUTTON.button_com.gpio, &GPIO_InitStructure);
GPIO_WriteBit(BOARD_CONFIG_BUTTON.button_com.gpio, BOARD_CONFIG_BUTTON.button_com.gpio_pin, 0);
gpio_release(BOARD_CONFIG_BUTTON.button_com.gpio);
}
static void initialize_button(const ButtonConfig* config) {
// Configure the pin itself
gpio_use(config->gpio);
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_StructInit(&GPIO_InitStructure);
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_PuPd = config->pull;
GPIO_InitStructure.GPIO_Pin = config->gpio_pin;
GPIO_Init(config->gpio, &GPIO_InitStructure);
gpio_release(config->gpio);
}
bool button_is_pressed(ButtonId id) {
const ButtonConfig* button_config = &BOARD_CONFIG_BUTTON.buttons[id];
gpio_use(button_config->gpio);
uint8_t bit = GPIO_ReadInputDataBit(button_config->gpio, button_config->gpio_pin);
gpio_release(button_config->gpio);
return (BOARD_CONFIG_BUTTON.active_high) ? bit : !bit;
}
uint8_t button_get_state_bits(void) {
uint8_t button_state = 0x00;
for (int i = 0; i < NUM_BUTTONS; ++i) {
button_state |= (button_is_pressed(i) ? 0x01 : 0x00) << i;
}
return button_state;
}
void button_init(void) {
periph_config_acquire_lock();
periph_config_enable(SYSCFG, RCC_APB2Periph_SYSCFG);
initialize_button_common();
for (int i = 0; i < NUM_BUTTONS; ++i) {
initialize_button(&BOARD_CONFIG_BUTTON.buttons[i]);
}
periph_config_disable(SYSCFG, RCC_APB2Periph_SYSCFG);
periph_config_release_lock();
}
bool button_selftest(void) {
return button_get_state_bits() == 0;
}
void command_button_read(const char* button_id_str) {
int button = atoi(button_id_str);
if (button < 0 || button >= NUM_BUTTONS) {
prompt_send_response("Invalid button");
return;
}
if (button_is_pressed(button)) {
prompt_send_response("down");
} else {
prompt_send_response("up");
}
}