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package joule
import (
"errors"
"fmt"
"sync"
multierror "github.com/hashicorp/go-multierror"
"gobot.io/x/gobot"
"gobot.io/x/gobot/drivers/i2c"
"gobot.io/x/gobot/sysfs"
)
type sysfsPin struct {
pin int
pwmPin int
}
// Adaptor represents an Intel Joule
type Adaptor struct {
name string
digitalPins map[int]*sysfs.DigitalPin
pwmPins map[int]*sysfs.PWMPin
i2cBuses [3]i2c.I2cDevice
connect func(e *Adaptor) (err error)
mutex *sync.Mutex
}
// NewAdaptor returns a new Joule Adaptor
func NewAdaptor() *Adaptor {
return &Adaptor{
name: gobot.DefaultName("Joule"),
connect: func(e *Adaptor) (err error) {
return
},
mutex: &sync.Mutex{},
}
}
// Name returns the Adaptors name
func (e *Adaptor) Name() string { return e.name }
// SetName sets the Adaptors name
func (e *Adaptor) SetName(n string) { e.name = n }
// Connect initializes the Joule for use with the Arduino beakout board
func (e *Adaptor) Connect() (err error) {
e.mutex.Lock()
defer e.mutex.Unlock()
e.digitalPins = make(map[int]*sysfs.DigitalPin)
e.pwmPins = make(map[int]*sysfs.PWMPin)
err = e.connect(e)
return
}
// Finalize releases all i2c devices and exported digital and pwm pins.
func (e *Adaptor) Finalize() (err error) {
e.mutex.Lock()
defer e.mutex.Unlock()
for _, pin := range e.digitalPins {
if pin != nil {
if errs := pin.Unexport(); errs != nil {
err = multierror.Append(err, errs)
}
}
}
for _, pin := range e.pwmPins {
if pin != nil {
if errs := pin.Enable(false); errs != nil {
err = multierror.Append(err, errs)
}
if errs := pin.Unexport(); errs != nil {
err = multierror.Append(err, errs)
}
}
}
for _, bus := range e.i2cBuses {
if bus != nil {
if errs := bus.Close(); errs != nil {
err = multierror.Append(err, errs)
}
}
}
return
}
// digitalPin returns matched digitalPin for specified values
func (e *Adaptor) DigitalPin(pin string, dir string) (sysfsPin sysfs.DigitalPinner, err error) {
e.mutex.Lock()
defer e.mutex.Unlock()
i := sysfsPinMap[pin]
if e.digitalPins[i.pin] == nil {
e.digitalPins[i.pin] = sysfs.NewDigitalPin(i.pin)
if err = e.digitalPins[i.pin].Export(); err != nil {
return
}
}
if dir == "in" {
if err = e.digitalPins[i.pin].Direction(sysfs.IN); err != nil {
return
}
} else if dir == "out" {
if err = e.digitalPins[i.pin].Direction(sysfs.OUT); err != nil {
return
}
}
return e.digitalPins[i.pin], nil
}
// DigitalRead reads digital value from pin
func (e *Adaptor) DigitalRead(pin string) (i int, err error) {
sysfsPin, err := e.DigitalPin(pin, "in")
if err != nil {
return
}
return sysfsPin.Read()
}
// DigitalWrite writes a value to the pin. Acceptable values are 1 or 0.
func (e *Adaptor) DigitalWrite(pin string, val byte) (err error) {
sysfsPin, err := e.DigitalPin(pin, "out")
if err != nil {
return
}
return sysfsPin.Write(int(val))
}
// PwmWrite writes the 0-254 value to the specified pin
func (e *Adaptor) PwmWrite(pin string, val byte) (err error) {
pwmPin, err := e.PWMPin(pin)
if err != nil {
return
}
period, err := pwmPin.Period()
if err != nil {
return err
}
duty := gobot.FromScale(float64(val), 0, 255.0)
return pwmPin.SetDutyCycle(uint32(float64(period) * duty))
}
// PWMPin returns a sysfs.PWMPin
func (e *Adaptor) PWMPin(pin string) (sysfsPin sysfs.PWMPinner, err error) {
e.mutex.Lock()
defer e.mutex.Unlock()
sysPin, ok := sysfsPinMap[pin]
if !ok {
err = errors.New("Not a valid pin")
return
}
if sysPin.pwmPin != -1 {
if e.pwmPins[sysPin.pwmPin] == nil {
e.pwmPins[sysPin.pwmPin] = sysfs.NewPWMPin(sysPin.pwmPin)
if err = e.pwmPins[sysPin.pwmPin].Export(); err != nil {
return
}
if err = e.pwmPins[sysPin.pwmPin].SetPeriod(10000000); err != nil {
return
}
if err = e.pwmPins[sysPin.pwmPin].Enable(true); err != nil {
return
}
}
sysfsPin = e.pwmPins[sysPin.pwmPin]
return
}
err = errors.New("Not a PWM pin")
return
}
// GetConnection returns an i2c connection to a device on a specified bus.
// Valid bus number is [0..2] which corresponds to /dev/i2c-0 through /dev/i2c-2.
func (e *Adaptor) GetConnection(address int, bus int) (connection i2c.Connection, err error) {
if (bus < 0) || (bus > 2) {
return nil, fmt.Errorf("Bus number %d out of range", bus)
}
if e.i2cBuses[bus] == nil {
e.i2cBuses[bus], err = sysfs.NewI2cDevice(fmt.Sprintf("/dev/i2c-%d", bus))
}
return i2c.NewConnection(e.i2cBuses[bus], address), err
}
// GetDefaultBus returns the default i2c bus for this platform
func (e *Adaptor) GetDefaultBus() int {
return 0
}
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