From 42a907035b2191fb9cebbd0424ffa12e9c364354 Mon Sep 17 00:00:00 2001
From: deadprogram <ron@hybridgroup.com>
Date: Sun, 18 Oct 2020 21:22:56 +0200
Subject: [PATCH] spi: incorporate change from GH issue feedback

Signed-off-by: deadprogram <ron@hybridgroup.com>
---
 apa102/apa102.go     | 8 --------
 spi.go               | 6 ++++++
 wifinina/wifinina.go | 2 +-
 3 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/apa102/apa102.go b/apa102/apa102.go
index a2d6ed9..4a8ab9a 100644
--- a/apa102/apa102.go
+++ b/apa102/apa102.go
@@ -29,14 +29,6 @@ type Device struct {
 	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 drivers.SPI) Device {
 	return Device{bus: b, Order: BGR}
diff --git a/spi.go b/spi.go
index f908afe..aa9e410 100644
--- a/spi.go
+++ b/spi.go
@@ -2,6 +2,12 @@ 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)
 }
diff --git a/wifinina/wifinina.go b/wifinina/wifinina.go
index 64f1129..a984ff3 100644
--- a/wifinina/wifinina.go
+++ b/wifinina/wifinina.go
@@ -269,7 +269,7 @@ type Device struct {
 	ssids [10]string
 }
 
-// New returns a new Wiifinina driver.
+// New returns a new Wifinina driver.
 func New(bus drivers.SPI, csPin, ackPin, gpio0Pin, resetPin machine.Pin) *Device {
 	return &Device{
 		SPI:   bus,