circuitpython/ports/raspberrypi/common-hal/paralleldisplaybus/ParallelBus.c

173 lines
6.8 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2021 Scott Shawcroft for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "shared-bindings/paralleldisplaybus/ParallelBus.h"
#include <stdint.h>
#include "common-hal/microcontroller/Pin.h"
#include "py/runtime.h"
#include "shared-bindings/digitalio/DigitalInOut.h"
#include "shared-bindings/microcontroller/__init__.h"
#include "bindings/rp2pio/StateMachine.h"
#include "common-hal/rp2pio/StateMachine.h"
static const uint16_t parallel_program[] = {
// .side_set 1
// .wrap_target
0x6008, // out pins, 8 side 0
0xB042 // nop side 1
// .wrap
};
void common_hal_paralleldisplaybus_parallelbus_construct(paralleldisplaybus_parallelbus_obj_t *self,
const mcu_pin_obj_t *data0, const mcu_pin_obj_t *command, const mcu_pin_obj_t *chip_select,
const mcu_pin_obj_t *write, const mcu_pin_obj_t *read, const mcu_pin_obj_t *reset, uint32_t frequency) {
uint8_t data_pin = data0->number;
for (uint8_t i = 0; i < 8; i++) {
if (!pin_number_is_free(data_pin + i)) {
mp_raise_ValueError_varg(MP_ERROR_TEXT("Bus pin %d is already in use"), i);
}
}
uint8_t write_pin = write->number;
if (!pin_number_is_free(write_pin)) {
mp_raise_ValueError_varg(MP_ERROR_TEXT("Bus pin %d is already in use"), write_pin);
}
self->command.base.type = &digitalio_digitalinout_type;
common_hal_digitalio_digitalinout_construct(&self->command, command);
common_hal_digitalio_digitalinout_switch_to_output(&self->command, true, DRIVE_MODE_PUSH_PULL);
self->chip_select.base.type = &digitalio_digitalinout_type;
common_hal_digitalio_digitalinout_construct(&self->chip_select, chip_select);
common_hal_digitalio_digitalinout_switch_to_output(&self->chip_select, true, DRIVE_MODE_PUSH_PULL);
self->read.base.type = &mp_type_NoneType;
if (read != NULL) {
self->read.base.type = &digitalio_digitalinout_type;
common_hal_digitalio_digitalinout_construct(&self->read, read);
common_hal_digitalio_digitalinout_switch_to_output(&self->read, true, DRIVE_MODE_PUSH_PULL);
never_reset_pin_number(read->number);
}
self->data0_pin = data_pin;
self->write = write_pin;
self->reset.base.type = &mp_type_NoneType;
if (reset != NULL) {
self->reset.base.type = &digitalio_digitalinout_type;
common_hal_digitalio_digitalinout_construct(&self->reset, reset);
common_hal_digitalio_digitalinout_switch_to_output(&self->reset, true, DRIVE_MODE_PUSH_PULL);
never_reset_pin_number(reset->number);
common_hal_paralleldisplaybus_parallelbus_reset(self);
}
never_reset_pin_number(command->number);
never_reset_pin_number(chip_select->number);
never_reset_pin_number(write_pin);
for (uint8_t i = 0; i < 8; i++) {
never_reset_pin_number(data_pin + i);
}
common_hal_rp2pio_statemachine_construct(&self->state_machine,
parallel_program, MP_ARRAY_SIZE(parallel_program),
frequency * 2, // frequency multiplied by 2 as 2 PIO instructions
NULL, 0, // init
NULL, 0, // may_exec
data0, 8, 0, 255, // first out pin, # out pins
NULL, 0, 0, 0, // first in pin, # in pins
NULL, 0, 0, 0, // first set pin
write, 1, 0, 1, // first sideset pin
false, // No sideset enable
NULL, PULL_NONE, // jump pin
0, // wait gpio pins
true, // exclusive pin usage
true, 8, true, // TX, auto pull every 8 bits. shift left to output msb first
false, // wait for TX stall
false, 32, true, // RX setting we don't use
false, // Not user-interruptible.
0, -1, // wrap settings
PIO_ANY_OFFSET);
common_hal_rp2pio_statemachine_never_reset(&self->state_machine);
}
void common_hal_paralleldisplaybus_parallelbus_deinit(paralleldisplaybus_parallelbus_obj_t *self) {
common_hal_rp2pio_statemachine_deinit(&self->state_machine);
for (uint8_t i = 0; i < 8; i++) {
reset_pin_number(self->data0_pin + i);
}
reset_pin_number(self->command.pin->number);
reset_pin_number(self->chip_select.pin->number);
reset_pin_number(self->write);
if (self->read.base.type != &mp_type_NoneType) {
reset_pin_number(self->read.pin->number);
}
if (self->reset.base.type != &mp_type_NoneType) {
reset_pin_number(self->reset.pin->number);
}
}
bool common_hal_paralleldisplaybus_parallelbus_reset(mp_obj_t obj) {
paralleldisplaybus_parallelbus_obj_t *self = MP_OBJ_TO_PTR(obj);
if (self->reset.base.type == &mp_type_NoneType) {
return false;
}
common_hal_digitalio_digitalinout_set_value(&self->reset, false);
common_hal_mcu_delay_us(4);
common_hal_digitalio_digitalinout_set_value(&self->reset, true);
return true;
}
bool common_hal_paralleldisplaybus_parallelbus_bus_free(mp_obj_t obj) {
return true;
}
bool common_hal_paralleldisplaybus_parallelbus_begin_transaction(mp_obj_t obj) {
paralleldisplaybus_parallelbus_obj_t *self = MP_OBJ_TO_PTR(obj);
common_hal_digitalio_digitalinout_set_value(&self->chip_select, false);
return true;
}
void common_hal_paralleldisplaybus_parallelbus_send(mp_obj_t obj, display_byte_type_t byte_type,
display_chip_select_behavior_t chip_select, const uint8_t *data, uint32_t data_length) {
paralleldisplaybus_parallelbus_obj_t *self = MP_OBJ_TO_PTR(obj);
common_hal_digitalio_digitalinout_set_value(&self->command, byte_type == DISPLAY_DATA);
common_hal_rp2pio_statemachine_write(&self->state_machine, data, data_length, 1, false);
}
void common_hal_paralleldisplaybus_parallelbus_end_transaction(mp_obj_t obj) {
paralleldisplaybus_parallelbus_obj_t *self = MP_OBJ_TO_PTR(obj);
common_hal_digitalio_digitalinout_set_value(&self->chip_select, true);
}