diff --git a/drivers/aio/analog_sensor_driver.go b/drivers/aio/analog_sensor_driver.go index 450265955..e5bfa22a4 100644 --- a/drivers/aio/analog_sensor_driver.go +++ b/drivers/aio/analog_sensor_driver.go @@ -1,6 +1,7 @@ package aio import ( + "sync" "time" "gobot.io/x/gobot/v2" @@ -18,6 +19,7 @@ type AnalogSensorDriver struct { rawValue int value float64 scale func(input int) (value float64) + mutex *sync.Mutex // to prevent data race between cyclic and single shot write/read to values and scaler } // NewAnalogSensorDriver returns a new AnalogSensorDriver with a polling interval of @@ -43,6 +45,7 @@ func NewAnalogSensorDriver(a AnalogReader, pin string, v ...time.Duration) *Anal interval: 10 * time.Millisecond, halt: make(chan bool), scale: func(input int) (value float64) { return float64(input) }, + mutex: &sync.Mutex{}, } if len(v) > 0 { @@ -83,16 +86,16 @@ func (a *AnalogSensorDriver) Start() (err error) { timer := time.NewTimer(a.interval) timer.Stop() for { - _, err := a.Read() + rawValue, value, err := a.analogRead() if err != nil { a.Publish(a.Event(Error), err) } else { - if a.rawValue != oldRawValue && a.rawValue != -1 { - a.Publish(a.Event(Data), a.rawValue) - oldRawValue = a.rawValue + if rawValue != oldRawValue && rawValue != -1 { + a.Publish(a.Event(Data), rawValue) + oldRawValue = rawValue } - if a.value != oldValue && a.value != -1 { - a.Publish(a.Event(Value), a.value) + if value != oldValue && value != -1 { + a.Publish(a.Event(Value), value) oldValue = a.value } } @@ -131,35 +134,57 @@ func (a *AnalogSensorDriver) Pin() string { return a.pin } // Connection returns the AnalogSensorDrivers Connection func (a *AnalogSensorDriver) Connection() gobot.Connection { return a.connection.(gobot.Connection) } -// Read returns the current reading from the sensor -func (a *AnalogSensorDriver) Read() (val float64, err error) { - if a.rawValue, err = a.ReadRaw(); err != nil { - return - } - a.value = a.scale(a.rawValue) - return a.value, nil +// Read returns the current reading from the sensor, scaled by the current scaler +func (a *AnalogSensorDriver) Read() (float64, error) { + _, value, err := a.analogRead() + return value, err } // ReadRaw returns the current reading from the sensor without scaling -func (a *AnalogSensorDriver) ReadRaw() (val int, err error) { - return a.connection.AnalogRead(a.Pin()) +func (a *AnalogSensorDriver) ReadRaw() (int, error) { + rawValue, _, err := a.analogRead() + return rawValue, err } // SetScaler substitute the default 1:1 return value function by a new scaling function func (a *AnalogSensorDriver) SetScaler(scaler func(int) float64) { + a.mutex.Lock() + defer a.mutex.Unlock() + a.scale = scaler } // Value returns the last read value from the sensor func (a *AnalogSensorDriver) Value() float64 { + a.mutex.Lock() + defer a.mutex.Unlock() + return a.value } // RawValue returns the last read raw value from the sensor func (a *AnalogSensorDriver) RawValue() int { + a.mutex.Lock() + defer a.mutex.Unlock() + return a.rawValue } +// analogRead performs an reading from the sensor and sets the internal attributes and returns the raw and scaled value +func (a *AnalogSensorDriver) analogRead() (int, float64, error) { + a.mutex.Lock() + defer a.mutex.Unlock() + + rawValue, err := a.connection.AnalogRead(a.Pin()) + if err != nil { + return 0, 0, err + } + + a.rawValue = rawValue + a.value = a.scale(a.rawValue) + return a.rawValue, a.value, nil +} + // AnalogSensorLinearScaler creates a linear scaler function from the given values. func AnalogSensorLinearScaler(fromMin, fromMax int, toMin, toMax float64) func(input int) (value float64) { m := (toMax - toMin) / float64(fromMax-fromMin)