PinInput+PinOutput HAL (#753, reloaded) (#795)

* first commit: add HAL and uc8151 driver demo
* unexport drivers.PinOutput/Input HAL
* fix non-tinygo pin config build
* change of heart
* docs: corrected some comments that were not changed at the same time as recent renaming

uc8151/uc8151.go

@@ -8,10 +8,11 @@ package uc8151 // import "tinygo.org/x/drivers/uc8151"
 import (
 	"errors"
 	"image/color"
-	"machine"
 	"time"
 
 	"tinygo.org/x/drivers"
+	"tinygo.org/x/drivers/internal/legacy"
+	"tinygo.org/x/drivers/internal/pin"
 	"tinygo.org/x/drivers/pixel"
 )
 
@@ -31,10 +32,10 @@ type Config struct {
 
 type Device struct {
 	bus                      drivers.SPI
-	cs                       machine.Pin
-	dc                       machine.Pin
-	rst                      machine.Pin
-	busy                     machine.Pin
+	cs                       pin.OutputFunc
+	dc                       pin.OutputFunc
+	rst                      pin.OutputFunc
+	isBusy                   pin.InputFunc
 	width                    int16
 	height                   int16
 	buffer                   []uint8
@@ -49,17 +50,22 @@ type Device struct {
 type Speed uint8
 
 // New returns a new uc8151 driver. Pass in a fully configured SPI bus.
-func New(bus drivers.SPI, csPin, dcPin, rstPin, busyPin machine.Pin) Device {
-	csPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
-	dcPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
-	rstPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
-	busyPin.Configure(machine.PinConfig{Mode: machine.PinInput})
+// Pins passed in must be configured beforehand.
+func New(bus drivers.SPI, csPin, dcPin, rstPin pin.Output, busyPin pin.Input) Device {
+	// For backwards compatibility.
+	// This driver used to configure pins,
+	// so leave in to not break users.
+	// May be removed in future so try not to depend on it!
+	legacy.ConfigurePinOut(csPin)
+	legacy.ConfigurePinOut(dcPin)
+	legacy.ConfigurePinOut(rstPin)
+	legacy.ConfigurePinInput(busyPin)
 	return Device{
-		bus:  bus,
-		cs:   csPin,
-		dc:   dcPin,
-		rst:  rstPin,
-		busy: busyPin,
+		bus:    bus,
+		cs:     csPin.Set,
+		dc:     dcPin.Set,
+		rst:    rstPin.Set,
+		isBusy: busyPin.Get,
 	}
 }
 
@@ -313,14 +319,14 @@ func (d *Device) ClearDisplay() {
 
 // WaitUntilIdle waits until the display is ready
 func (d *Device) WaitUntilIdle() {
-	for !d.busy.Get() {
+	for !d.isBusy() {
 		time.Sleep(10 * time.Millisecond)
 	}
 }
 
 // IsBusy returns the busy status of the display
 func (d *Device) IsBusy() bool {
-	return d.busy.Get()
+	return d.isBusy()
 }
 
 // ClearBuffer sets the buffer to 0xFF (white)