upm/src/apa102/apa102.cxx
Mihai Tudor Panu 2d2ee8d1f0 apa102: added extra functionality
Exposed call to MRAA SPI frequency for those super long strips where the clock signal will degrade and introduce glitches. Slowing down will fix it without the need for extra filtering or redrivers. Batch mode also helps since only one write per frame will be required.

Added functions that control brightness only for fade effects without the need to keep an extra copy of the pixel color map.

Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>
2016-08-25 17:33:41 -07:00

197 lines
4.9 KiB
C++

/*
* Author: Yannick Adam <yannick.adam@gmail.com>
* Copyright (c) 2016 Yannick Adam
*
* 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 <cstring>
#include <iostream>
#include <stdexcept>
#include <stdlib.h>
#include <unistd.h>
#include "apa102.hpp"
using namespace upm;
APA102::APA102(uint16_t ledCount, uint8_t spiBus, bool batchMode, int8_t csn)
: m_ledCount(ledCount), m_batchMode(batchMode)
{
mraa::Result res = mraa::SUCCESS;
m_leds = NULL;
// Optional chip select pin
m_csnPinCtx = NULL;
if (csn > -1) {
m_csnPinCtx = new mraa::Gpio(csn);
res = m_csnPinCtx->dir(mraa::DIR_OUT);
if (res != mraa::SUCCESS) {
throw std::invalid_argument(std::string(__FUNCTION__) +
": GPIO failed to set direction");
}
}
CSOff();
// Initialize SPI
m_spi = new mraa::Spi(spiBus);
// Initialize LED array
uint16_t endFrameLength = (m_ledCount + 15) / 16; // End frame should be (leds/2) bits
m_frameLength = endFrameLength + (m_ledCount + 1) * 4;
if ((m_leds = (uint8_t*) malloc(m_frameLength))) {
memset(m_leds, 0x00, m_frameLength - 4); // Clear state
memset(&m_leds[m_frameLength - endFrameLength], 0xFF, endFrameLength); // Frame End
// Need to set the brightness to "0" for each Led
for (int i = 1; i <= m_ledCount; i++) {
m_leds[i * 4] = 224;
}
} else {
throw std::runtime_error(std::string(__FUNCTION__) +
": Failed to allocate memory for LED Strip");
}
}
APA102::~APA102()
{
// Clear leds
if (m_leds) {
free(m_leds);
}
// Clear SPI
if (m_spi) {
delete m_spi;
}
// Clear GPIO
if (m_csnPinCtx) {
delete m_csnPinCtx;
}
}
void
APA102::setLed(uint16_t ledIdx, uint8_t brightness, uint8_t r, uint8_t g, uint8_t b)
{
setLeds(ledIdx, ledIdx, brightness, r, g, b);
}
void
APA102::setLedBrightness(uint16_t ledIdx, uint8_t brightness)
{
setLedsBrightness(ledIdx, ledIdx, brightness);
}
void
APA102::setAllLeds(uint8_t brightness, uint8_t r, uint8_t g, uint8_t b)
{
setLeds(0, m_ledCount - 1, brightness, r, g, b);
}
void
APA102::setLeds(uint16_t startIdx, uint16_t endIdx, uint8_t brightness, uint8_t r, uint8_t g, uint8_t b)
{
uint16_t s_idx = (startIdx + 1) * 4;
uint16_t e_idx = (endIdx + 1) * 4;
for (uint16_t i = s_idx; i <= e_idx; i += 4) {
m_leds[i] = brightness | 224;
m_leds[i + 1] = b;
m_leds[i + 2] = g;
m_leds[i + 3] = r;
}
if (!m_batchMode) {
pushState();
}
}
void
APA102::setLedsBrightness(uint16_t startIdx, uint16_t endIdx, uint8_t brightness)
{
uint16_t s_idx = (startIdx + 1) * 4;
uint16_t e_idx = (endIdx + 1) * 4;
for (uint16_t i = s_idx; i <= e_idx; i += 4) {
m_leds[i] = brightness | 224;
}
if (!m_batchMode) {
pushState();
}
}
void
APA102::setLeds(uint16_t startIdx, uint16_t endIdx, uint8_t* colors)
{
uint16_t s_idx = (startIdx + 1) * 4;
memcpy(&m_leds[s_idx], colors, (endIdx - startIdx + 1) * 4);
if (!m_batchMode) {
pushState();
}
}
void
APA102::setBusSpeed(int hz)
{
if (m_spi->frequency(hz) != mraa::SUCCESS) {
throw std::runtime_error(std::string(__FUNCTION__) +
": Failed to change SPI bus speed");
}
}
void
APA102::pushState(void)
{
CSOn();
m_spi->write(m_leds, m_frameLength);
CSOff();
}
/*
* **************
* private area
* **************
*/
mraa::Result
APA102::CSOn()
{
if (m_csnPinCtx) {
return m_csnPinCtx->write(HIGH);
}
return mraa::ERROR_FEATURE_NOT_SUPPORTED;
}
mraa::Result
APA102::CSOff()
{
if (m_csnPinCtx) {
return m_csnPinCtx->write(LOW);
}
return mraa::ERROR_FEATURE_NOT_SUPPORTED;
}