eboled: Initial implementation

This driver supports the Sparkfun 64x48 pixel OLED Edison block:

https://www.sparkfun.com/products/13035

It is based on an ssd1306, but with some modifications (custom COM pin
mapping and a custom column offset).  It uses SPI to communicate, and
since it is an Edison Block, you don't really have any options for
different bus and pin assignments.

Signed-off-by: Jon Trulson <jtrulson@ics.com>
Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>

src/lcd/eboled.cxx

@@ -0,0 +1,203 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * 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 <unistd.h>
+#include <iostream>
+
+#include "eboled.h"
+
+using namespace upm;
+using namespace std;
+
+EBOLED::EBOLED(int spi, int CD, int reset) : 
+  m_spi(spi), m_gpioCD(CD), m_gpioRST(reset)
+{
+  m_name = "EBOLED";
+  
+  m_gpioCD.dir(mraa::DIR_OUT);
+  m_gpioRST.dir(mraa::DIR_OUT);
+
+  m_spi.frequency(1000000);
+
+  // reset the device
+  m_gpioRST.write(1);
+  usleep(5000);
+  m_gpioRST.write(0);
+  usleep(10000);
+  m_gpioRST.write(1);
+
+  command(CMD_DISPLAYOFF);
+
+  command(CMD_SETDISPLAYCLOCKDIV);
+  command(0x80);
+
+  command(CMD_SETMULTIPLEX);
+  command(0x2f);
+  
+  command(CMD_SETDISPLAYOFFSET);
+  command(0x0);                 // no offset
+  
+  command(CMD_SETSTARTLINE | 0x0); // line #0
+  
+  command(CMD_CHARGEPUMP);      // enable charge pump
+  command(0x14);
+  
+  command(CMD_NORMALDISPLAY);
+  command(CMD_DISPLAYALLONRESUME);
+  
+  command(CMD_SEGREMAP | 0x1);  // reverse mapping (SEG0==COL127)
+  command(CMD_COMSCANDEC);
+  
+  command(CMD_SETCOMPINS);      // custom COM PIN mapping
+  command(0x12);
+  
+  command(CMD_SETCONTRAST);
+  command(0x8f);
+  
+  command(CMD_SETPRECHARGE);
+  command(0xf1);
+  
+  command(CMD_SETVCOMDESELECT);
+  command(0x40);
+  
+  command(CMD_DISPLAYON);
+  
+
+  usleep(4500);
+  
+  clear();
+  setAddressingMode(PAGE);
+}
+
+EBOLED::~EBOLED()
+{
+  clear();
+}
+
+mraa_result_t EBOLED::draw(uint8_t* bdata, int bytes)
+{
+  mraa_result_t error = MRAA_SUCCESS;
+
+  setAddressingMode(HORIZONTAL);
+
+  command(CMD_SETCOLUMNADDRESS); // triple-byte cmd
+  command(0x20); // this display has a horizontal offset of 20 columns
+  command(0x20 + 0x40); // 64 columns wide
+
+  for (int idx = 0; idx < bytes; idx++)
+    error = data(bdata[idx]);
+
+  // reset addressing mode
+  setAddressingMode(PAGE);
+
+  return error;
+}
+
+mraa_result_t EBOLED::write(std::string msg)
+{
+  mraa_result_t error = MRAA_SUCCESS;
+
+  setAddressingMode(PAGE);
+  for (std::string::size_type i = 0; i < msg.size(); ++i)
+    error = writeChar(msg[i]);
+
+  return error;
+}
+
+mraa_result_t EBOLED::setCursor(int row, int column)
+{
+  mraa_result_t error = MRAA_SUCCESS;
+
+  // set page address
+  error = command(CMD_SETPAGESTARTADDR | (row & 0x07));
+
+  // set column address
+  error = command(CMD_SETLOWCOLUMN | (column & 0x0f));
+  // ediblock oled starts at col 20 apparently...
+  error = command(CMD_SETHIGHCOLUMN | ((column >> 4) & 0x0f) + 0x02);
+
+  return error;
+}
+
+mraa_result_t EBOLED::clear()
+{
+  mraa_result_t error = MRAA_SUCCESS;
+  uint8_t columnIdx, rowIdx;
+  
+  for (rowIdx = 0; rowIdx < 8; rowIdx++)
+    {
+      setCursor(rowIdx, 0);
+      
+      // clear all columns (8 * 8 pixels per char)
+      for (columnIdx = 0; columnIdx < 8; columnIdx++)
+        error = writeChar(' ');
+    }
+  
+  home();
+  
+  return MRAA_SUCCESS;
+}
+
+mraa_result_t EBOLED::home()
+{
+  return setCursor(0, 0);
+}
+
+mraa_result_t EBOLED::writeChar(uint8_t value)
+{
+  mraa_result_t rv;
+
+  if (value < 0x20 || value > 0x7F) {
+    value = 0x20; // space
+  }
+
+  for (uint8_t idx = 0; idx < 8; idx++) {
+    rv = data(BasicFont[value - 32][idx]);
+  }
+
+  return rv;
+}
+
+mraa_result_t EBOLED::setAddressingMode(displayAddressingMode mode)
+{
+  mraa_result_t rv;
+
+  rv = command(CMD_MEMORYADDRMODE);
+  rv = command(mode);
+
+  return rv;
+}
+
+mraa_result_t EBOLED::command(uint8_t cmd)
+{
+  m_gpioCD.write(0);            // command mode
+  m_spi.writeByte(cmd);
+  return MRAA_SUCCESS;
+}
+
+mraa_result_t EBOLED::data(uint8_t data)
+{
+  m_gpioCD.write(1);            // data mode
+  m_spi.writeByte(data);
+  return MRAA_SUCCESS;
+}