com.diozero.internal.soc.broadcom.BroadcomMmapGpio Maven / Gradle / Ivy
package com.diozero.internal.soc.broadcom;
/*
* #%L
* Organisation: diozero
* Project: diozero - Core
* Filename: BroadcomMmapGpio.java
*
* This file is part of the diozero project. More information about this project
* can be found at https://www.diozero.com/.
* %%
* Copyright (C) 2016 - 2024 diozero
* %%
* 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.
* #L%
*/
import java.nio.ByteOrder;
import java.util.Optional;
import org.tinylog.Logger;
import com.diozero.api.DeviceMode;
import com.diozero.api.GpioPullUpDown;
import com.diozero.internal.board.raspberrypi.RaspberryPiBoardInfoProvider;
import com.diozero.internal.spi.MmapGpioInterface;
import com.diozero.util.MmapIntBuffer;
import com.diozero.util.SleepUtil;
/**
* https://datasheets.raspberrypi.org/bcm2835/bcm2835-peripherals.pdf
*/
public class BroadcomMmapGpio implements MmapGpioInterface {
/*-
* The BCM2835 has 54 GPIO pins.
* BCM2835 data sheet, Page 90 onwards.
* There are 6 control registers, each control the functions of a block
* of 10 pins.
* Each control register has 10 sets of 3 bits per GPIO pin - the ALT values
* 000 = GPIO Pin X is an input
* 001 = GPIO Pin X is an output
* 100 = GPIO Pin X takes alternate function 0
* 101 = GPIO Pin X takes alternate function 1
* 110 = GPIO Pin X takes alternate function 2
* 111 = GPIO Pin X takes alternate function 3
* 011 = GPIO Pin X takes alternate function 4
* 010 = GPIO Pin X takes alternate function 5
*/
private static final int FSEL_INPT = 0b000;
private static final int FSEL_OUTP = 0b001;
private static final int FSEL_ALT0 = 0b100;
private static final int FSEL_ALT1 = 0b101;
private static final int FSEL_ALT2 = 0b110;
private static final int FSEL_ALT3 = 0b111;
private static final int FSEL_ALT4 = 0b011;
private static final int FSEL_ALT5 = 0b010;
// #define GPIO_BASE (pi_peri_phys + 0x00200000)
// #define PCM_BASE (pi_peri_phys + 0x00203000)
// #define SPI_BASE (pi_peri_phys + 0x00204000)
// #define PWM_BASE (pi_peri_phys + 0x0020C000)
private static final String GPIOMEM_DEVICE = "/dev/gpiomem";
// private static final int GPIOMEM_LEN = 0xB4;
private static final int GPIOMEM_LEN = 4096;
// Offset to the GPIO Set registers for each GPIO pin
private static final byte[] GPIO_TO_GPSET = { 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8 };
// Offset to the GPIO Clear registers for each GPIO pin
private static final byte[] GPIO_TO_GPCLR = { 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11 };
// Offset to the GPIO Input level registers for each GPIO pin
private static final byte[] GPIO_TO_GPLEV = { 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14 };
/* BCM2711 has different pulls */
private static final int GPPUPPDN0 = 57;
/*-
private static final int GPPUPPDN1 = 58;
private static final int GPPUPPDN2 = 59;
private static final int GPPUPPDN3 = 60;
*/
// GPIO Pin pull up/down register
private static final byte GPPUD = 37;
// Offset to the Pull Up Down Clock register
private static byte[] GPIO_TO_PUDCLK = { 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38,
38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39,
39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39 };
private static final int PI_2711_PUD_OFF = 0;
private static final int PI_2711_PUD_DOWN = 2;
private static final int PI_2711_PUD_UP = 1;
private static final int PI_28XX_PUD_OFF = 0;
private static final int PI_28XX_PUD_DOWN = 1;
private static final int PI_28XX_PUD_UP = 2;
private boolean initialised;
private boolean piIs2711;
private MmapIntBuffer mmapIntBuffer;
public BroadcomMmapGpio(String soc) {
this.piIs2711 = soc.equals(RaspberryPiBoardInfoProvider.BCM2711);
}
@Override
public synchronized void initialise() {
if (!initialised) {
// Note /dev/gpiomem device ignores any offset and always grants access to the
// GPIO register area
if (mmapIntBuffer == null) {
mmapIntBuffer = new MmapIntBuffer(GPIOMEM_DEVICE, 0, GPIOMEM_LEN, ByteOrder.LITTLE_ENDIAN);
}
initialised = true;
}
}
@Override
public synchronized void close() {
if (initialised) {
mmapIntBuffer.close();
mmapIntBuffer = null;
}
}
/**
* Returns the function of a GPIO: 0=input, 1=output, 4=alt0
*
* @param gpio GPIO number
* @return GPIO mode (0 - INPUT, 1 - OUTPUT)
*/
@Override
public DeviceMode getMode(int gpio) {
int reg = gpio / 10;
int shift = (gpio % 10) * 3;
/*-
* See BCM2385 data sheet page 102.
*
* PWM0 can be on GPIOs 12, 18, 40, 52
* PWM1 can on on GPIOs 13, 19, 41, 45, 53
* FSEL_ALT0 (func=4=0b100) for PWM output for pins 12, 13, 40, 41 and 45
* FSEL_ALT1 (func=5=0b101) for PWM output for pins 52 and 53
* FSEL_ALT5 (func=2=0b010) for PWM output for pins 18 and 19
*/
int mode = mmapIntBuffer.getShiftRight(reg, shift, 7);
Logger.debug("mode for {}: {}", Integer.valueOf(gpio), Integer.valueOf(mode));
DeviceMode device_mode = DeviceMode.UNKNOWN;
switch (mode) {
case FSEL_INPT:
device_mode = DeviceMode.DIGITAL_INPUT;
break;
case FSEL_OUTP:
device_mode = DeviceMode.DIGITAL_OUTPUT;
break;
case FSEL_ALT0:
if (gpio == 12 || gpio == 13 || gpio == 40 || gpio == 41 || gpio == 45) {
device_mode = DeviceMode.PWM_OUTPUT;
} else if (gpio >= 0 && gpio < 4 || gpio >= 28 && gpio < 30) {
device_mode = DeviceMode.I2C;
} else if (gpio >= 7 && gpio < 12) {
device_mode = DeviceMode.SPI;
} else if (gpio >= 14 && gpio < 16) {
device_mode = DeviceMode.SERIAL;
}
break;
case FSEL_ALT1:
if (gpio == 52 || gpio == 53) {
device_mode = DeviceMode.PWM_OUTPUT;
} else if (gpio == 44 || gpio == 45) {
device_mode = DeviceMode.I2C;
}
break;
case FSEL_ALT2:
if (gpio >= 36 && gpio < 40) {
device_mode = DeviceMode.SERIAL;
} else if (gpio == 44 || gpio == 45) {
device_mode = DeviceMode.I2C;
}
break;
case FSEL_ALT3:
if (gpio >= 16 && gpio < 18 || gpio >= 30 && gpio < 34) {
device_mode = DeviceMode.SERIAL;
}
break;
case FSEL_ALT4:
if (gpio >= 16 && gpio < 22 || gpio >= 40 && gpio < 46) {
device_mode = DeviceMode.SPI;
}
break;
case FSEL_ALT5:
if (gpio >= 14 && gpio < 18 || gpio >= 30 && gpio < 34 || gpio >= 40 && gpio < 44) {
device_mode = DeviceMode.SERIAL;
} else if (gpio == 18 || gpio == 19) {
device_mode = DeviceMode.PWM_OUTPUT;
}
break;
default:
// Ignore
}
return device_mode;
}
@Override
public void setMode(int gpio, DeviceMode mode) {
switch (mode) {
case DIGITAL_INPUT:
// mmapIntBuffer.put(reg, mmapIntBuffer.get(reg) & ~(0b111 << shift));
setModeUnchecked(gpio, 0);
break;
case DIGITAL_OUTPUT:
// mmapIntBuffer.put(reg, mmapIntBuffer.get(reg) & ~(0b111 << shift) | (1 <<
// shift));
setModeUnchecked(gpio, 1);
break;
case PWM_OUTPUT:
int m_val;
if (gpio == 12 || gpio == 13 || gpio == 40 || gpio == 41 || gpio == 45) {
m_val = FSEL_ALT0;
} else if (gpio == 52 || gpio == 53) {
m_val = FSEL_ALT1;
} else if (gpio == 18 || gpio == 19) {
m_val = FSEL_ALT5;
} else {
throw new IllegalArgumentException("Invalid GPIO mode " + mode + " for pin " + gpio);
}
// mmapIntBuffer.put(reg, mmapIntBuffer.get(reg) & ~(7 << shift) | (m_val <<
// shift));
setModeUnchecked(gpio, m_val);
break;
default:
throw new IllegalArgumentException("Invalid GPIO mode " + mode + " for pin " + gpio);
}
}
@Override
public void setModeUnchecked(int gpio, int mode) {
int reg = gpio / 10;
int shift = (gpio % 10) * 3;
mmapIntBuffer.put(reg, mmapIntBuffer.get(reg) & ~(0b111 << shift) | (mode << shift));
}
@Override
public Optional getPullUpDown(int gpio) {
if (!piIs2711) {
return Optional.empty();
}
int pud_int_offset = GPPUPPDN0 + (gpio >> 4);
int pud_shift = (gpio & 0xf) << 1;
GpioPullUpDown pud;
switch ((mmapIntBuffer.get(pud_int_offset) >> pud_shift) & 0b11) {
case PI_2711_PUD_UP:
pud = GpioPullUpDown.PULL_UP;
break;
case PI_2711_PUD_DOWN:
pud = GpioPullUpDown.PULL_DOWN;
break;
default:
pud = GpioPullUpDown.NONE;
}
return Optional.of(pud);
}
@Override
public void setPullUpDown(int gpio, GpioPullUpDown pud) {
// See pigpio: https://github.com/joan2937/pigpio/blob/master/pigpio.c#L8880
if (piIs2711) {
int pull;
switch (pud) {
case PULL_UP:
pull = PI_2711_PUD_UP;
break;
case PULL_DOWN:
pull = PI_2711_PUD_DOWN;
break;
case NONE:
default:
pull = PI_2711_PUD_OFF;
break;
}
/*-
*
bits = *(gpioReg + GPPUPPDN0 + (gpio>>4));
bits &= ~(3 << shift);
bits |= (pull << shift);
*(gpioReg + GPPUPPDN0 + (gpio>>4)) = bits;
*/
int pud_int_offset = GPPUPPDN0 + (gpio >> 4);
int pud_shift = (gpio & 0xf) << 1;
int reg_val = mmapIntBuffer.get(pud_int_offset);
reg_val &= ~(0b11 << pud_shift);
reg_val |= (pull << pud_shift);
mmapIntBuffer.put(pud_int_offset, reg_val);
} else {
int pull;
switch (pud) {
case PULL_UP:
pull = PI_28XX_PUD_UP;
break;
case PULL_DOWN:
pull = PI_28XX_PUD_DOWN;
break;
case NONE:
default:
pull = PI_28XX_PUD_OFF;
break;
}
/*-
#define BANK (gpio >> 5)
#define BIT (1 << (gpio & 0x1F))
*(gpioReg + GPPUD) = pud;
myGpioDelay(1);
*(gpioReg + GPPUDCLK0 + BANK) = BIT;
myGpioDelay(1);
*(gpioReg + GPPUD) = 0;
*(gpioReg + GPPUDCLK0 + BANK) = 0;
*/
mmapIntBuffer.put(GPPUD, pull);
SleepUtil.busySleep(1_000);
mmapIntBuffer.put(GPIO_TO_PUDCLK[gpio], 1 << (gpio & 0x1F));
SleepUtil.busySleep(1_000);
mmapIntBuffer.put(GPPUD, 0);
mmapIntBuffer.put(GPIO_TO_PUDCLK[gpio], 0);
}
}
@Override
public boolean gpioRead(int gpio) {
// return (gpioReg.get(GPLEV0 + (gpio >> 5)) & (1 << (gpio & 0x1F))) != 0;
// return (mmapIntBuffer.get(GPIO_TO_GPLEV[gpio]) & (1 << (gpio & 0x1F))) != 0;
return mmapIntBuffer.get(GPIO_TO_GPLEV[gpio], 1 << (gpio & 0x1F)) != 0;
}
@Override
public void gpioWrite(int gpio, boolean value) {
if (value) {
// pigpio
// gpioReg.put(GPSET0 + gpio >> 5, 1 << (gpio & 0x1F));
// wiringPi
mmapIntBuffer.put(GPIO_TO_GPSET[gpio], 1 << (gpio & 0x1F));
} else {
// pigpio
// gpioReg.put(GPCLR0 + gpio >> 5, 1 << (gpio & 0x1F));
// wiringPi
mmapIntBuffer.put(GPIO_TO_GPCLR[gpio], 1 << (gpio & 0x1F));
}
}
@SuppressWarnings("boxing")
public static void main(String[] args) {
String soc = RaspberryPiBoardInfoProvider.BCM2711;
if (args.length > 0) {
soc = args[0];
}
boolean PI_OFF = false;
boolean PI_ON = true;
try (BroadcomMmapGpio mmap = new BroadcomMmapGpio(soc)) {
mmap.initialise();
int gpio = 21;
for (int i = 0; i < 10; i++) {
mmap.setMode(gpio, DeviceMode.DIGITAL_INPUT);
System.out.format("Mode for GPIO# %d: %s, value: %b. (Mode should be %s)%n", gpio, mmap.getMode(gpio),
mmap.gpioRead(gpio), DeviceMode.DIGITAL_INPUT);
mmap.setMode(gpio, DeviceMode.DIGITAL_OUTPUT);
System.out.format("Mode for GPIO# %d: %s, value: %b. (Mode should be %s)%n", gpio, mmap.getMode(gpio),
mmap.gpioRead(gpio), DeviceMode.DIGITAL_OUTPUT);
mmap.gpioWrite(gpio, PI_ON);
System.out.format("Mode for GPIO# %d: %s, value: %b. (Value should be %b)%n", gpio, mmap.getMode(gpio),
mmap.gpioRead(gpio), PI_ON);
SleepUtil.sleepSeconds(1);
mmap.gpioWrite(gpio, PI_OFF);
System.out.format("Mode for GPIO# %d: %s, value: %b. (Value should be %b)%n", gpio, mmap.getMode(gpio),
mmap.gpioRead(gpio), PI_OFF);
SleepUtil.sleepSeconds(1);
}
}
}
}
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