php-linux-gpio/lib/Gpio.php

123 lines
3.1 KiB
PHP

<?php
/*
* Copyright (C) 2014, NoccyLabs
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>
*/
namespace NoccyLabs\Gpio;
use NoccyLabs\Gpio\Exception\HardwareException;
class Gpio implements \ArrayAccess
{
// Direction
const DIR_IN = "in";
const DIR_OUT = "out";
// Values
const VAL_HIGH = 1;
const VAL_LOW = 0;
// Edges
const EDGE_NONE = "none";
const EDGE_RISING = "rising";
const EDGE_FALLING = "faling";
const EDGE_BOTH = "both";
protected $gpio = array();
/** @var NoccyLabs\Gpio\GpioMapperInterface */
protected $mapper;
public function __construct($force=false)
{
if (!$force) {
if (!file_exists("/sys/class/gpio")) {
throw new HardwareException("gpio sysfs is not available");
}
if (!is_writable("/sys/class/gpio/export")) {
throw new HardwareException("gpio sysfs is not writable");
}
}
}
public function refresh()
{
$read = $this->fd_gpio;
$write = array();
$except = $read;
if (count($read)>0) {
stream_select($read, $write, $except, 0);
foreach($except as $fd) {
$pin = $this->getPinFromFd($fd);
$pin->doInterrupt();
}
}
}
public function getPinFromFd($fd)
{
foreach($this->fd_pins as $pinfd=>$pin) {
if ($pinfd == $fd) { return $pin; }
}
return false;
}
protected $fd_gpio = array();
protected $fd_pins = array();
public function enableInterrupt(GpioPin $pin, $fd)
{
$this->fd_gpio[] = $fd;
$this->fd_pins[$fd] = $pin;
}
public function disableInterrupt(GpioPin $pin)
{
}
public function setMapper(GpioMapperInterface $mapper=null)
{
$this->mapper = $mapper;
return $this;
}
public function offsetGet($index)
{
if ($this->mapper) { $index = $this->mapper->mapLogicalToGpioPin($index); }
if (empty($this->gpio[$index])) {
$this->gpio[$index] = new GpioPin($index, $this);
}
return $this->gpio[$index];
}
public function offsetExists($index)
{
return array_key_exists($index, $this->gpio);
}
public function offsetSet($index,$value)
{ throw new \Exception(); }
public function offsetUnset($index)
{
unset($this->gpio[$index]);
}
}