spi: remove machine.SPI and replace with drivers.SPI interface

.circleci/config.yml

@@ -12,6 +12,9 @@ jobs:
       - run:
           name: "Enforce Go Formatted Code"
           command: make fmt-check
+      - run:
+          name: "Run unit tests"
+          command: make unit-test
       - run:
           name: "Run build and smoke tests"
           command: make smoke-test

Makefile

@@ -158,4 +158,13 @@ endif
 	tinygo build -size short -o ./build/test.hex -target=circuitplay-express ./examples/lis2mdl/main.go
 	@md5sum ./build/test.hex
 
-test: clean fmt-check smoke-test
+DRIVERS = $(wildcard */)
+NOTESTS = build examples flash semihosting pcd8544 shiftregister st7789 microphone mcp3008 gps microbitmatrix \
+		hcsr04 ssd1331 ws2812 thermistor apa102 easystepper ssd1351 ili9341 wifinina shifter hub75 \
+		hd44780 buzzer ssd1306 espat l9110x st7735 bmi160 l293x
+TESTS = $(filter-out $(addsuffix /%,$(NOTESTS)),$(DRIVERS))
+
+unit-test:
+	@go test -v $(addprefix ./,$(TESTS)) 
+
+test: clean fmt-check unit-test smoke-test

apa102/apa102.go

@@ -6,6 +6,8 @@ package apa102 // import "tinygo.org/x/drivers/apa102"
 import (
 	"image/color"
 	"machine"
+
+	"tinygo.org/x/drivers"
 )
 
 const (
@@ -23,20 +25,12 @@ var startFrame = []byte{0x00, 0x00, 0x00, 0x00}
 
 // Device wraps APA102 SPI LEDs.
 type Device struct {
-	bus   SPI
+	bus   drivers.SPI
 	Order int
 }
 
-// The SPI interface specifies the minimum functionality that a bus
-// implementation needs to provide for use by the APA102 driver.  Hardware
-// SPI from the TinyGo "machine" package implements this already.
-type SPI interface {
-	Tx(w, r []byte) error
-	Transfer(b byte) (byte, error)
-}
-
 // New returns a new APA102 driver. Pass in a fully configured SPI bus.
-func New(b SPI) Device {
+func New(b drivers.SPI) Device {
 	return Device{bus: b, Order: BGR}
 }
 

bmi160/bmi160.go

@@ -1,8 +1,11 @@
 package bmi160
 
-import "machine"
+import (
+	"machine"
+	"time"
 
-import "time"
+	"tinygo.org/x/drivers"
+)
 
 // DeviceSPI is the SPI interface to a BMI160 accelerometer/gyroscope. There is
 // also an I2C interface, but it is not yet supported.
@@ -11,13 +14,13 @@ type DeviceSPI struct {
 	CSB machine.Pin
 
 	// SPI bus (requires chip select to be usable).
-	Bus machine.SPI
+	Bus drivers.SPI
 }
 
 // NewSPI returns a new device driver. The pin and SPI interface are not
 // touched, provide a fully configured SPI object and call Configure to start
 // using this device.
-func NewSPI(csb machine.Pin, spi machine.SPI) *DeviceSPI {
+func NewSPI(csb machine.Pin, spi drivers.SPI) *DeviceSPI {
 	return &DeviceSPI{
 		CSB: csb, // chip select
 		Bus: spi,

examples/wifinina/mqttclient/main.go

@@ -41,15 +41,7 @@ var (
 	spi  = machine.NINA_SPI
 
 	// this is the ESP chip that has the WIFININA firmware flashed on it
-	adaptor = &wifinina.Device{
-		SPI:   spi,
-		CS:    machine.NINA_CS,
-		ACK:   machine.NINA_ACK,
-		GPIO0: machine.NINA_GPIO0,
-		RESET: machine.NINA_RESETN,
-	}
-
-	console = machine.UART0
+	adaptor *wifinina.Device
 	topic   = "tinygo"
 )
 
@@ -68,6 +60,11 @@ func main() {
 	})
 
 	// Init esp8266/esp32
+	adaptor = wifinina.New(spi,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
 	adaptor.Configure()
 
 	connectToAP()

examples/wifinina/mqttsub/main.go

@@ -40,15 +40,7 @@ var (
 	spi  = machine.NINA_SPI
 
 	// this is the ESP chip that has the WIFININA firmware flashed on it
-	adaptor = &wifinina.Device{
-		SPI:   spi,
-		CS:    machine.NINA_CS,
-		ACK:   machine.NINA_ACK,
-		GPIO0: machine.NINA_GPIO0,
-		RESET: machine.NINA_RESETN,
-	}
-
-	console = machine.UART0
+	adaptor *wifinina.Device
 
 	cl      mqtt.Client
 	topicTx = "tinygo/tx"
@@ -75,6 +67,11 @@ func main() {
 	})
 
 	// Init esp8266/esp32
+	adaptor = wifinina.New(spi,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
 	adaptor.Configure()
 
 	connectToAP()

examples/wifinina/ntpclient/main.go

@@ -24,20 +24,9 @@ const ntpHost = "129.6.15.29"
 const NTP_PACKET_SIZE = 48
 
 var (
-
 	// this is the ESP chip that has the WIFININA firmware flashed on it
-	// these are the default pins for the Arduino Nano33 IoT.
-	adaptor = wifinina.Device{
-		SPI:   machine.NINA_SPI,
-		CS:    machine.NINA_CS,
-		ACK:   machine.NINA_ACK,
-		GPIO0: machine.NINA_GPIO0,
-		RESET: machine.NINA_RESETN,
-	}
-
-	b = make([]byte, NTP_PACKET_SIZE)
-
-	console = machine.UART0
+	adaptor *wifinina.Device
+	b       = make([]byte, NTP_PACKET_SIZE)
 )
 
 func main() {
@@ -50,6 +39,14 @@ func main() {
 		SDI:       machine.NINA_SDI,
 		SCK:       machine.NINA_SCK,
 	})
+
+	// these are the default pins for the Arduino Nano33 IoT.
+	adaptor = wifinina.New(machine.NINA_SPI,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
+
 	adaptor.Configure()
 
 	// connect to access point

examples/wifinina/tcpclient/main.go

@@ -35,15 +35,7 @@ var (
 	spi  = machine.NINA_SPI
 
 	// this is the ESP chip that has the WIFININA firmware flashed on it
-	adaptor = &wifinina.Device{
-		SPI:   spi,
-		CS:    machine.NINA_CS,
-		ACK:   machine.NINA_ACK,
-		GPIO0: machine.NINA_GPIO0,
-		RESET: machine.NINA_RESETN,
-	}
-
-	console = machine.UART0
+	adaptor *wifinina.Device
 )
 
 var buf = &bytes.Buffer{}
@@ -60,6 +52,11 @@ func main() {
 		SCK:       machine.NINA_SCK,
 	})
 
+	adaptor = wifinina.New(spi,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
 	adaptor.Configure()
 
 	connectToAP()

examples/wifinina/udpstation/main.go

@@ -22,19 +22,9 @@ const pass = ""
 // IP address of the server aka "hub". Replace with your own info.
 const hubIP = ""
 
-// these are the default pins for the Arduino Nano33 IoT.
-// change these to connect to a different UART or pins for the ESP8266/ESP32
 var (
-
 	// this is the ESP chip that has the WIFININA firmware flashed on it
-	// these are the default pins for the Arduino Nano33 IoT.
-	adaptor = &wifinina.Device{
-		SPI:   machine.NINA_SPI,
-		CS:    machine.NINA_CS,
-		ACK:   machine.NINA_ACK,
-		GPIO0: machine.NINA_GPIO0,
-		RESET: machine.NINA_RESETN,
-	}
+	adaptor *wifinina.Device
 )
 
 func main() {
@@ -47,6 +37,14 @@ func main() {
 		SDI:       machine.NINA_SDI,
 		SCK:       machine.NINA_SCK,
 	})
+
+	// these are the default pins for the Arduino Nano33 IoT.
+	// change these to connect to a different UART or pins for the ESP8266/ESP32
+	adaptor = wifinina.New(machine.NINA_SPI,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
 	adaptor.Configure()
 
 	// connect to access point

examples/wifinina/webclient/main.go

@@ -33,15 +33,7 @@ var (
 	spi  = machine.NINA_SPI
 
 	// this is the ESP chip that has the WIFININA firmware flashed on it
-	adaptor = &wifinina.Device{
-		SPI:   spi,
-		CS:    machine.NINA_CS,
-		ACK:   machine.NINA_ACK,
-		GPIO0: machine.NINA_GPIO0,
-		RESET: machine.NINA_RESETN,
-	}
-
-	console = machine.UART0
+	adaptor *wifinina.Device
 )
 
 var buf [256]byte
@@ -61,6 +53,11 @@ func main() {
 		SCK:       machine.NINA_SCK,
 	})
 
+	adaptor = wifinina.New(spi,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
 	adaptor.Configure()
 
 	connectToAP()

flash/flash.go

@@ -133,6 +133,8 @@ func (dev *Device) Configure(config *DeviceConfig) (err error) {
 	time.Sleep(30 * time.Microsecond)
 
 	// Speed up to max device frequency
+	// I propose a check here for max frequency, but not put that functionality directly into the driver.
+	// Either that or we have to change the signature of the SPI interface in the machine package itself.
 	if dev.attrs.MaxClockSpeedMHz > 0 {
 		err := dev.trans.setClockSpeed(uint32(dev.attrs.MaxClockSpeedMHz) * 1e6)
 		if err != nil {

flash/transport_spi.go

@@ -1,6 +1,8 @@
 package flash
 
-import "machine"
+import (
+	"machine"
+)
 
 type transport interface {
 	configure(config *DeviceConfig)

hub75/hub75.go

@@ -9,6 +9,8 @@ import (
 	"image/color"
 	"machine"
 	"time"
+
+	"tinygo.org/x/drivers"
 )
 
 type Config struct {
@@ -21,7 +23,7 @@ type Config struct {
 }
 
 type Device struct {
-	bus               machine.SPI
+	bus               drivers.SPI
 	a                 machine.Pin
 	b                 machine.Pin
 	c                 machine.Pin
@@ -52,7 +54,7 @@ type Device struct {
 }
 
 // New returns a new HUB75 driver. Pass in a fully configured SPI bus.
-func New(b machine.SPI, latPin, oePin, aPin, bPin, cPin, dPin machine.Pin) Device {
+func New(b drivers.SPI, latPin, oePin, aPin, bPin, cPin, dPin machine.Pin) Device {
 	aPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
 	bPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
 	cPin.Configure(machine.PinConfig{Mode: machine.PinOutput})

mcp3008/mcp3008.go

@@ -7,11 +7,13 @@ package mcp3008 // import "tinygo.org/x/drivers/mcp3008"
 import (
 	"errors"
 	"machine"
+
+	"tinygo.org/x/drivers"
 )
 
 // Device wraps MCP3008 SPI ADC.
 type Device struct {
-	bus machine.SPI
+	bus drivers.SPI
 	cs  machine.Pin
 	tx  []byte
 	rx  []byte
@@ -32,7 +34,7 @@ type ADCPin struct {
 }
 
 // New returns a new MCP3008 driver. Pass in a fully configured SPI bus.
-func New(b machine.SPI, csPin machine.Pin) *Device {
+func New(b drivers.SPI, csPin machine.Pin) *Device {
 	d := &Device{bus: b,
 		cs: csPin,
 		tx: make([]byte, 3),

pcd8544/pcd8544.go

@@ -9,11 +9,13 @@ import (
 	"image/color"
 	"machine"
 	"time"
+
+	"tinygo.org/x/drivers"
 )
 
 // Device wraps an SPI connection.
 type Device struct {
-	bus        machine.SPI
+	bus        drivers.SPI
 	dcPin      machine.Pin
 	rstPin     machine.Pin
 	scePin     machine.Pin
@@ -29,7 +31,7 @@ type Config struct {
 }
 
 // New creates a new PCD8544 connection. The SPI bus must already be configured.
-func New(bus machine.SPI, dcPin, rstPin, scePin machine.Pin) *Device {
+func New(bus drivers.SPI, dcPin, rstPin, scePin machine.Pin) *Device {
 	return &Device{
 		bus:    bus,
 		dcPin:  dcPin,

spi.go

@@ -0,0 +1,13 @@
+package drivers
+
+// SPI represents a SPI bus. It is implemented by the machine.SPI type.
+type SPI interface {
+	// Tx transmits the given buffer w and receives at the same time the buffer r.
+	// The two buffers must be the same length. The only exception is when w or r are nil,
+	// in which case Tx only transmits (without receiving) or only receives (while sending 0 bytes).
+	Tx(w, r []byte) error
+
+	// Transfer writes a single byte out on the SPI bus and receives a byte at the same time.
+	// If you want to transfer multiple bytes, it is more efficient to use Tx instead.
+	Transfer(b byte) (byte, error)
+}