Permalink
Fetching contributors…
Cannot retrieve contributors at this time
543 lines (467 sloc) 14.8 KB
/*
SwiftyGPIO
Copyright (c) 2016 Umberto Raimondi
Licensed under the MIT license, as follows:
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.)
*/
#if os(Linux)
import Glibc
#else
import Darwin.C
#endif
import Foundation
internal let GPIOBASEPATH="/sys/class/gpio/"
// MARK: GPIO
public class GPIO {
public var bounceTime: TimeInterval?
public private(set) var name: String = ""
public private(set) var id: Int = 0
var exported = false
var listening = false
var intThread: Thread?
var intFalling: (func: ((GPIO) -> Void), lastCall: Date?)?
var intRaising: (func: ((GPIO) -> Void), lastCall: Date?)?
var intChange: (func: ((GPIO) -> Void), lastCall: Date?)?
public init(name: String,
id: Int) {
self.name = name
self.id = id
}
public var direction: GPIODirection {
set(dir) {
if !exported {enableIO(id)}
performSetting("gpio" + String(id) + "/direction", value: dir.rawValue)
}
get {
if !exported { enableIO(id)}
return GPIODirection(rawValue: getStringValue("gpio"+String(id)+"/direction")!)!
}
}
public var edge: GPIOEdge {
set(dir) {
if !exported {enableIO(id)}
performSetting("gpio"+String(id)+"/edge", value: dir.rawValue)
}
get {
if !exported {enableIO(id)}
return GPIOEdge(rawValue: getStringValue("gpio"+String(id)+"/edge")!)!
}
}
public var activeLow: Bool {
set(act) {
if !exported {enableIO(id)}
performSetting("gpio"+String(id)+"/active_low", value: act ? "1":"0")
}
get {
if !exported {enableIO(id)}
return getIntValue("gpio"+String(id)+"/active_low")==0
}
}
public var pull: GPIOPull {
set(dir) {
fatalError("Unsupported parameter.")
}
get{
fatalError("Parameter cannot be read.")
}
}
public var value: Int {
set(val) {
if !exported {enableIO(id)}
performSetting("gpio"+String(id)+"/value", value: val)
}
get {
if !exported {enableIO(id)}
return getIntValue("gpio"+String(id)+"/value")!
}
}
public func isMemoryMapped() -> Bool {
return false
}
public func onFalling(_ closure: @escaping (GPIO) -> Void) {
intFalling = (func: closure, lastCall: nil)
if intThread == nil {
intThread = makeInterruptThread()
listening = true
intThread?.start()
}
}
public func onRaising(_ closure: @escaping (GPIO) -> Void) {
intRaising = (func: closure, lastCall: nil)
if intThread == nil {
intThread = makeInterruptThread()
listening = true
intThread?.start()
}
}
public func onChange(_ closure: @escaping (GPIO) -> Void) {
intChange = (func: closure, lastCall: nil)
if intThread == nil {
intThread = makeInterruptThread()
listening = true
intThread?.start()
}
}
public func clearListeners() {
(intFalling, intRaising, intChange) = (nil, nil, nil)
listening = false
}
}
fileprivate extension GPIO {
func enableIO(_ id: Int) {
writeToFile(GPIOBASEPATH+"export", value:String(id))
exported = true
}
func performSetting(_ filename: String, value: String) {
writeToFile(GPIOBASEPATH+filename, value:value)
}
func performSetting(_ filename: String, value: Int) {
writeToFile(GPIOBASEPATH+filename, value: String(value))
}
func getStringValue(_ filename: String) -> String? {
return readFromFile(GPIOBASEPATH+filename)
}
func getIntValue(_ filename: String) -> Int? {
if let res = readFromFile(GPIOBASEPATH+filename) {
return Int(res)
}
return nil
}
func writeToFile(_ path: String, value: String) {
let fp = fopen(path, "w")
if fp != nil {
#if swift(>=3.2)
let len = value.count
#else
let len = value.characters.count
#endif
let ret = fwrite(value, MemoryLayout<CChar>.stride, len, fp)
if ret<len {
if ferror(fp) != 0 {
perror("Error while writing to file")
abort()
}
}
fclose(fp)
}
}
func readFromFile(_ path: String) -> String? {
let MAXLEN = 8
let fp = fopen(path, "r")
var res: String?
if fp != nil {
let buf = UnsafeMutablePointer<CChar>.allocate(capacity: MAXLEN)
let len = fread(buf, MemoryLayout<CChar>.stride, MAXLEN, fp)
if len < MAXLEN {
if ferror(fp) != 0 {
perror("Error while reading from file")
abort()
}
}
fclose(fp)
//Remove the trailing \n
buf[len-1]=0
res = String.init(validatingUTF8: buf)
#if swift(>=4.1)
buf.deallocate()
#else
buf.deallocate(capacity: MAXLEN)
#endif
}
return res
}
func makeInterruptThread() -> Thread? {
//Ignored by Linux
guard #available(iOS 10.0, macOS 10.12, *) else {return nil}
let thread = Thread {
let gpath = GPIOBASEPATH+"gpio"+String(self.id)+"/value"
self.direction = .IN
self.edge = .BOTH
let fp = open(gpath, O_RDONLY)
var buf: [Int8] = [0, 0, 0] //Dummy read to discard current value
read(fp, &buf, 3)
#if swift(>=4.0)
var pfd = pollfd(fd:fp, events:Int16(truncatingIfNeeded:POLLPRI), revents:0)
#else
var pfd = pollfd(fd:fp, events:Int16(truncatingBitPattern:POLLPRI), revents:0)
#endif
while self.listening {
let ready = poll(&pfd, 1, -1)
if ready > -1 {
lseek(fp, 0, SEEK_SET)
read(fp, &buf, 2)
buf[1]=0
let res = String(validatingUTF8: buf)!
switch res {
case "0":
self.interrupt(type: &(self.intFalling))
case "1":
self.interrupt(type: &(self.intRaising))
default:
break
}
self.interrupt(type: &(self.intChange))
}
}
}
return thread
}
func interrupt(type: inout (func: ((GPIO) -> Void), lastCall: Date?)?) {
guard let itype = type else {
return
}
if let interval = self.bounceTime, let lastCall = itype.lastCall, Date().timeIntervalSince(lastCall) < interval {
return
}
itype.func(self)
type?.lastCall = Date()
}
}
extension GPIO: CustomStringConvertible {
public var description: String {
return "\(name)<\(direction),\(edge),\(activeLow),\(pull)>: \(value)"
}
}
// MARK: GPIO:Raspberry
public final class RaspberryGPIO: GPIO {
var setGetId: UInt32 = 0
var baseAddr: Int = 0
var inited = false
let BCM2708_PERI_BASE: Int
let GPIO_BASE: Int
var gpioBasePointer: UnsafeMutablePointer<UInt32>!
var gpioGetPointer: UnsafeMutablePointer<UInt32>!
var gpioSetPointer: UnsafeMutablePointer<UInt32>!
var gpioClearPointer: UnsafeMutablePointer<UInt32>!
public init(name: String, id: Int, baseAddr: Int) {
self.setGetId = UInt32(1<<id)
self.BCM2708_PERI_BASE = baseAddr
self.GPIO_BASE = BCM2708_PERI_BASE + 0x200000 /* GPIO controller */
super.init(name:name, id:id)
}
public override var value: Int {
set(val) {
if !inited {initIO()}
gpioSet(val)
}
get {
if !inited {initIO()}
return gpioGet()
}
}
public override var direction: GPIODirection {
set(dir) {
if !inited {initIO()}
if dir == .IN {
gpioAsInput()
} else {
gpioAsOutput()
}
}
get {
if !inited {initIO()}
return gpioGetDirection()
}
}
public override var pull: GPIOPull {
set(pull) {
if !exported {enableIO(id)}
setGpioPull(pull)
}
get{
fatalError("Parameter cannot be read.")
}
}
public override func isMemoryMapped() -> Bool {
return true
}
private func initIO() {
var mem_fd: Int32 = 0
//Try to open one of the mem devices
for device in ["/dev/gpiomem", "/dev/mem"] {
mem_fd=open(device, O_RDWR | O_SYNC)
if mem_fd>0 {
break
}
}
guard mem_fd > 0 else {
fatalError("Can't open /dev/mem , use sudo!")
}
let gpio_map = mmap(
nil, //Any adddress in our space will do
PAGE_SIZE, //Map length
PROT_READ|PROT_WRITE, // Enable reading & writting to mapped memory
MAP_SHARED, //Shared with other processes
mem_fd, //File to map
off_t(GPIO_BASE) //Offset to GPIO peripheral, i.e. GPFSEL0
)!
close(mem_fd)
if (Int(bitPattern: gpio_map) == -1) { //MAP_FAILED not available, but its value is (void*)-1
perror("mmap error")
abort()
}
gpioBasePointer = gpio_map.assumingMemoryBound(to: UInt32.self)
gpioGetPointer = gpioBasePointer.advanced(by: 13) // GPLEV0
gpioSetPointer = gpioBasePointer.advanced(by: 7) // GPSET0
gpioClearPointer = gpioBasePointer.advanced(by: 10) // GPCLR0
inited = true
}
private func gpioAsInput() {
let ptr = gpioBasePointer.advanced(by: id/10) // GPFSELn 0..5
ptr.pointee &= ~(7<<((UInt32(id)%10)*3)) // SEL=000 input
}
private func gpioAsOutput() {
let ptr = gpioBasePointer.advanced(by: id/10) // GPFSELn 0..5
ptr.pointee &= ~(7<<((UInt32(id)%10)*3))
ptr.pointee |= (1<<((UInt32(id)%10)*3)) // SEL=001 output
}
private func gpioGetDirection() -> GPIODirection {
let ptr = gpioBasePointer.advanced(by: id/10) // GPFSELn 0..5
let d = (ptr.pointee & (7<<((UInt32(id)%10)*3)))
return (d == 0) ? .IN : .OUT
}
func setGpioPull(_ value: GPIOPull){
let gpioGPPUDPointer = gpioBasePointer.advanced(by: 37)
gpioGPPUDPointer.pointee = value.rawValue // Configure GPPUD
usleep(10); // 150 cycles or more
let gpioGPPUDCLK0Pointer = gpioBasePointer.advanced(by: 38)
gpioGPPUDCLK0Pointer.pointee = setGetId // Configure GPPUDCLK0 for specific gpio (Ids always lower than 31, no GPPUDCLK1 needed)
usleep(10); // 150 cycles or more
gpioGPPUDPointer.pointee = 0 // Reset GPPUD
usleep(10); // 150 cycles or more
gpioGPPUDCLK0Pointer.pointee = 0 // Reset GPPUDCLK0/1 for specific gpio
usleep(10); // 150 cycles or more
}
private func gpioGet() -> Int {
return ((gpioGetPointer.pointee & setGetId)>0) ? 1 : 0
}
private func gpioSet(_ value: Int) {
let ptr = value==1 ? gpioSetPointer : gpioClearPointer
ptr!.pointee = setGetId
}
}
public struct SwiftyGPIO {
public static func GPIOs(for board: SupportedBoard) -> [GPIOName: GPIO] {
switch board {
case .RaspberryPiRev1:
return GPIORPIRev1
case .RaspberryPiRev2:
return GPIORPIRev2
case .RaspberryPiPlusZero:
return GPIORPIPlusZERO
case .RaspberryPi2:
fallthrough
case .RaspberryPi3:
return GPIORPI2
case .CHIP:
return GPIOCHIP
case .BeagleBoneBlack:
return GPIOBEAGLEBONE
case .OrangePi:
return GPIOORANGEPI
case .OrangePiZero:
return GPIOORANGEPIZERO
}
}
}
// MARK: - Global Enums
public enum SupportedBoard {
case RaspberryPiRev1 // Pi A,B Revision 1
case RaspberryPiRev2 // Pi A,B Revision 2
case RaspberryPiPlusZero // Pi A+,B+,Zero with 40 pin header
case RaspberryPi2 // Pi 2 with 40 pin header
case RaspberryPi3 // Pi 3 with 40 pin header
case CHIP
case BeagleBoneBlack
case OrangePi
case OrangePiZero
}
public enum GPIOName {
case P0
case P1
case P2
case P3
case P4
case P5
case P6
case P7
case P8
case P9
case P10
case P11
case P12
case P13
case P14
case P15
case P16
case P17
case P18
case P19
case P20
case P21
case P22
case P23
case P24
case P25
case P26
case P27
case P28
case P29
case P30
case P31
case P32
case P33
case P34
case P35
case P36
case P37
case P38
case P39
case P40
case P41
case P42
case P43
case P44
case P45
case P46
case P47
}
public enum GPIODirection: String {
case IN="in"
case OUT="out"
}
public enum GPIOEdge: String {
case NONE="none"
case RISING="rising"
case FALLING="falling"
case BOTH="both"
}
public enum GPIOPull: UInt32 {
case neither = 0
case down = 1
case up = 2
}
public enum ByteOrder {
case MSBFIRST
case LSBFIRST
}
// MARK: - Constants
let PAGE_SIZE = (1 << 12)
// MARK: - Darwin / Xcode Support
#if os(OSX) || os(iOS)
private var O_SYNC: CInt { fatalError("Linux only") }
#endif