From cdffd77a38c8340a5f4a8ffba4d6538bb32f3854 Mon Sep 17 00:00:00 2001
From: Christopher Vagnetoft <cvagnetoft@gmail.com>
Date: Sat, 14 Jun 2014 03:10:07 +0200
Subject: [PATCH] Added software spi stuff

---
 examples/softwarespi.php   | 25 +++++++++++
 lib/Bus/Bus.php            | 64 ++++++++++++++++++++++++++
 lib/Bus/BusInterface.php   | 42 +++++++++++++++++
 lib/Bus/SoftwareSpiBus.php | 92 ++++++++++++++++++++++++++++++++++++++
 lib/GpioPin.php            |  3 +-
 lib/Util/BitmappedGpio.php | 17 +++++++
 6 files changed, 241 insertions(+), 2 deletions(-)
 create mode 100644 examples/softwarespi.php
 create mode 100644 lib/Bus/Bus.php
 create mode 100644 lib/Bus/BusInterface.php
 create mode 100644 lib/Bus/SoftwareSpiBus.php

diff --git a/examples/softwarespi.php b/examples/softwarespi.php
new file mode 100644
index 0000000..cbd777d
--- /dev/null
+++ b/examples/softwarespi.php
@@ -0,0 +1,25 @@
+<?php
+
+require_once __DIR__."/../vendor/autoload.php";
+require_once __DIR__."/GLOBALS.php";
+
+use NoccyLabs\Gpio\Gpio;
+use NoccyLabs\Gpio\GpioTickHandler;
+use NoccyLabs\Gpio\Bus\SoftwareSpiBus as SPI;
+use NoccyLabs\Crap\Dumper;
+
+$gpio = new Gpio(true);
+
+// create spi bus
+$spi = new SPI();
+// bind the spi pins
+$spi->sclk = $gpio[1];
+$spi->mosi = $gpio[2];
+$spi->miso = $gpio[3];
+// write to the spi bus
+$spi->write("\xBE\xEF");
+// read the two bytes exchanged with the write()
+$read = $spi->read(2);
+
+// 
+Dumper::dump($read);
diff --git a/lib/Bus/Bus.php b/lib/Bus/Bus.php
new file mode 100644
index 0000000..3d46374
--- /dev/null
+++ b/lib/Bus/Bus.php
@@ -0,0 +1,64 @@
+<?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\Bus;
+
+abstract class Bus implements BusInterface
+{
+    protected $pins = array();
+
+    public function __construct()
+    {
+        $this->configure();
+    }
+    
+    public function addPin($name)
+    {
+        $this->pins[$name] = null;
+    }
+    
+    public function __set($name, $value)
+    {
+        if (!array_key_exists($name,$this->pins)) {
+            throw new \Exception("No such pin: {$name}");
+        }
+        $this->pins[$name] = $value;
+    }
+    
+    public function __get($name)
+    {
+        if (!array_key_exists($name,$this->pins)) {
+            throw new \Exception("No such pin: {$name}");
+        }
+        return $this->pins[$name];
+    }
+
+    public function __isSet($name)
+    {
+        return array_key_exists($name,$this->pins);
+    }
+    
+    public function __unset($name)
+    {
+        if (!array_key_exists($name,$this->pins)) {
+            return;
+        }
+        $this->pins[$name] = null;
+    }
+}
diff --git a/lib/Bus/BusInterface.php b/lib/Bus/BusInterface.php
new file mode 100644
index 0000000..c81cf80
--- /dev/null
+++ b/lib/Bus/BusInterface.php
@@ -0,0 +1,42 @@
+<?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\Bus;
+
+interface BusInterface
+{
+    /**
+     * Write data to the bus. The data will be written immediately.
+     *
+     */
+    public function write($data);
+    
+    /**
+     * Read data from the buffer, or perform additional null reads over the 
+     * (SPI) bus to acquire the data.
+     *
+     */
+    public function read($bytes);
+    
+    /**
+     * Return the number of bytes in the read buffer
+     *
+     */
+    public function getBufferFill();
+}
diff --git a/lib/Bus/SoftwareSpiBus.php b/lib/Bus/SoftwareSpiBus.php
new file mode 100644
index 0000000..167d719
--- /dev/null
+++ b/lib/Bus/SoftwareSpiBus.php
@@ -0,0 +1,92 @@
+<?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\Bus;
+
+class SoftwareSpiBus extends Bus
+{
+    protected $buffer = null;
+
+    protected function configure()
+    {
+        $this->addPin("sclk");
+        $this->addPin("mosi");
+        $this->addPin("miso");
+    }
+
+    protected function spiExchangeByte($byte)
+    {
+        $in = 0;
+        if (is_string($byte)) { $byte = ord($byte); }
+        for($bit=0; $bit<8; $bit++) {
+            $this->setValue("sclk", 0);
+            $this->setValue("mosi", (($byte & 1<<$bit)>0));
+            usleep(5000);
+            $this->setValue("sclk", 1);
+            usleep(5000);
+            if ($this->getValue("miso")) {
+                $in |= 1<<$bit;
+            }
+        }
+        return chr($in);
+    }
+    
+    protected function setValue($pin,$value)
+    {
+        echo "{$pin}→{$value}\n";
+    }
+    protected function getValue($pin)
+    {
+        echo "{$pin}←0\n";
+        return 0;
+    }
+    
+    public function write($data)
+    {
+        for($n = 0; $n < strlen($data); $n++) {
+            $this->buffer .= $this->spiExchangeByte($data[$n]);
+        }
+    }
+    
+    public function read($bytes)
+    {
+        $ret = null;
+        if (strlen($this->buffer)>0) {
+            if (strlen($this->buffer)<$bytes) {
+                $ret = $this->buffer; 
+                $bytes -= strlen($this->buffer);
+                $this->buffer = null; 
+            } else {
+                $ret = substr($this->buffer,0,$bytes);
+                $this->buffer = substr($this->buffer,$bytes);
+                return $ret;
+            }
+        }
+        for($n = 0; $n < $bytes; $n++) {
+            $ret.= $this->spiExchangeByte(0x00);
+        }
+        return $ret;
+    }
+    
+    public function getBufferFill()
+    {
+        return strlen($this->buffer);
+    }
+
+}
diff --git a/lib/GpioPin.php b/lib/GpioPin.php
index 7ac8d35..df4363a 100644
--- a/lib/GpioPin.php
+++ b/lib/GpioPin.php
@@ -52,8 +52,6 @@ class GpioPin
     {
         $this->pin = (int)$pin;
         $this->gpio = $gpio;
-        $this->export();
-        $this->hardware = $this->findHardware();
     }
     
     private function findHardware()
@@ -139,6 +137,7 @@ class GpioPin
         if (!file_exists("/sys/class/gpio/gpio{$this->pin}")) {
             throw new HardwareException("Unable to export pin {$this->pin}");
         }
+        $this->hardware = $this->findHardware();
         return $this;
     }
     
diff --git a/lib/Util/BitmappedGpio.php b/lib/Util/BitmappedGpio.php
index 6d7971e..7d072ca 100644
--- a/lib/Util/BitmappedGpio.php
+++ b/lib/Util/BitmappedGpio.php
@@ -1,5 +1,22 @@
 <?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\Util;
 
 use NoccyLabs\Gpio\GpioPin;