Files
pebble/src/fw/services/prf/accessory/accessory_manager.c
2025-01-27 11:38:16 -08:00

133 lines
3.9 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 "accessory_manager.h"
#include "accessory_idle_mode.h"
#include "accessory_imaging.h"
#include "accessory_mfg_mode.h"
#include "drivers/accessory.h"
#include "system/logging.h"
#include "os/mutex.h"
static AccessoryInputState s_input_state = AccessoryInputStateIdle;
static PebbleMutex *s_state_mutex;
void accessory_manager_init(void) {
s_state_mutex = mutex_create();
}
bool accessory_manager_handle_character_from_isr(char c) {
// NOTE: THIS IS RUN WITHIN AN ISR
switch (s_input_state) {
case AccessoryInputStateMfg:
return accessory_mfg_mode_handle_char(c);
case AccessoryInputStateIdle:
return accessory_idle_mode_handle_char(c);
case AccessoryInputStateImaging:
return accessory_imaging_handle_char(c);
case AccessoryInputStateMic:
// fallthrough
default:
break;
}
return false;
}
bool accessory_manager_handle_break_from_isr(void) {
// NOTE: THIS IS RUN WITHIN AN ISR
switch (s_input_state) {
case AccessoryInputStateIdle:
case AccessoryInputStateMic:
case AccessoryInputStateMfg:
case AccessoryInputStateImaging:
// fallthrough
default:
break;
}
return false;
}
// Valid state transitions are:
// +-----+
// | IMG |
// +-----+
// ^
// |
// v
// +------+ +-----+ +-----+
// | Idle |<-->| MFG |<-->| MIC |
// +------+ +-----+ +-----+
static bool prv_is_valid_state_transition(AccessoryInputState new_state) {
if (s_input_state == AccessoryInputStateIdle) {
return new_state == AccessoryInputStateMfg;
} else if (s_input_state == AccessoryInputStateMfg) {
return (new_state == AccessoryInputStateIdle) ||
(new_state == AccessoryInputStateImaging) ||
(new_state == AccessoryInputStateMic);
} else if (s_input_state == AccessoryInputStateImaging) {
return new_state == AccessoryInputStateMfg;
} else if (s_input_state == AccessoryInputStateMic) {
return new_state == AccessoryInputStateMfg;
}
return false;
}
// The accessory state is used to differentiate between different consumers of the accessory port.
// Before a consumer uses the accessory port, it must set its state and return the state to idle
// once it has finished. No other consumer will be permitted to use the accessory port until the
// state is returned to idle.
bool accessory_manager_set_state(AccessoryInputState state) {
mutex_lock(s_state_mutex);
if (!prv_is_valid_state_transition(state)) {
// the state is already set by somebody else
mutex_unlock(s_state_mutex);
return false;
}
s_input_state = state;
switch (s_input_state) {
case AccessoryInputStateMfg:
accessory_enable_input();
accessory_set_baudrate(AccessoryBaud115200);
accessory_set_power(false);
accessory_mfg_mode_start();
break;
case AccessoryInputStateIdle:
// restore accessory to default state
accessory_enable_input();
accessory_set_baudrate(AccessoryBaud115200);
accessory_set_power(false);
break;
case AccessoryInputStateImaging:
accessory_enable_input();
accessory_set_baudrate(AccessoryBaud921600);
accessory_set_power(false);
break;
case AccessoryInputStateMic:
// fallthrough
default:
break;
}
mutex_unlock(s_state_mutex);
PBL_LOG(LOG_LEVEL_DEBUG, "Setting accessory state to %u", state);
return true;
}