1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
/*
Q Light Controller Plus
spioutthread.cpp
Copyright (c) Massimo Callegari
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0.txt
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include <QMutexLocker>
#include <QSettings>
#include <QDebug>
#include <time.h>
#include <sys/ioctl.h>
#include <linux/spi/spidev.h>
#include "spioutthread.h"
SPIOutThread::SPIOutThread()
: m_isRunning(false)
, m_dataSize(0)
, m_estimatedWireTime(50000)
{
}
void SPIOutThread::runThread(int fd, int speed)
{
if (fd < 0)
return;
m_spifd = fd;
m_speed = speed;
m_bitsPerWord = 8;
int mode = SPI_MODE_0;
int status = -1;
status = ioctl (m_spifd, SPI_IOC_WR_MODE, &mode);
if (status < 0)
qWarning() << "Could not set SPIMode (WR)...ioctl fail";
status = ioctl (m_spifd, SPI_IOC_WR_BITS_PER_WORD, &m_bitsPerWord);
if (status < 0)
qWarning() << "Could not set SPI bitsPerWord (WR)...ioctl fail";
status = ioctl (m_spifd, SPI_IOC_WR_MAX_SPEED_HZ, &m_speed);
if (status < 0)
qWarning() << "Could not set SPI speed (WR)...ioctl fail";
m_isRunning = true;
start();
}
void SPIOutThread::stopThread()
{
m_isRunning = false;
wait();
}
void SPIOutThread::setSpeed(int speed)
{
if (speed == m_speed)
return;
if (isRunning())
{
m_isRunning = false;
wait();
runThread(m_spifd, speed);
}
}
void SPIOutThread::run()
{
while (m_isRunning)
{
struct spi_ioc_transfer spi;
struct timespec ts_start;
struct timespec ts_end;
#ifdef CLOCK_MONOTONIC
clock_gettime(CLOCK_MONOTONIC, &ts_start);
#else
clock_gettime(CLOCK_REALTIME, &ts_start);
#endif
if (m_spifd != -1 && m_pluginData.size() > 0)
{
QMutexLocker locker(&m_mutex);
memset(&spi, 0, sizeof(spi));
spi.tx_buf = reinterpret_cast<__u64>(m_pluginData.data());
spi.len = m_pluginData.size();
spi.delay_usecs = 0;
spi.speed_hz = m_speed;
spi.bits_per_word = m_bitsPerWord;
spi.cs_change = 0;
int retVal = ioctl(m_spifd, SPI_IOC_MESSAGE(1), &spi);
if (retVal < 0)
qWarning() << "Problem transmitting SPI data: ioctl failed";
}
#ifdef CLOCK_MONOTONIC
clock_gettime(CLOCK_MONOTONIC, &ts_end);
#else
clock_gettime(CLOCK_REALTIME, &ts_end);
#endif
int uSecDiff = (difftime(ts_end.tv_sec, ts_start.tv_sec) * 1000000) + ((ts_end.tv_nsec - ts_start.tv_nsec) / 1000);
//qDebug() << "[SPI] ioctl took" << microseconds << "uSecDiff";
usleep(m_estimatedWireTime - uSecDiff);
}
}
void SPIOutThread::writeData(const QByteArray &data)
{
QMutexLocker locker(&m_mutex);
m_pluginData = data;
if (m_dataSize != data.size())
{
// Data size has changed! I need to estimate the
// time that the SPI writes will take on the wire.
// The estimation is very unprecise and it is based
// on Simon Newton's measurements on a Raspberry Pi
// where 512 bytes at 1Mhz takes about 70ms to be sent
double byteWriteTimeuS = (double)(70000.0 / ((double)m_speed / 1000000.0)) / 512.0; // time taken to write a byte
m_estimatedWireTime = byteWriteTimeuS * (double)data.size();
m_dataSize = data.size();
qDebug() << "[SPI out thread] estimated sleep time:" << m_estimatedWireTime;
}
}
|
