From 2e6bd46354a851f46de6efd5b587182c703819d4 Mon Sep 17 00:00:00 2001
From: Gavin Cabbage <gavincabbage@gmail.com>
Date: Sat, 29 Aug 2015 00:42:44 -0400
Subject: [PATCH] i2c: added ReadBytes to I2CBus

---
 host/generic/i2cbus.go | 22 ++++++++++++++++++++++
 i2c.go                 |  2 ++
 2 files changed, 24 insertions(+)

diff --git a/host/generic/i2cbus.go b/host/generic/i2cbus.go
index dc8e74c..45c5870 100644
--- a/host/generic/i2cbus.go
+++ b/host/generic/i2cbus.go
@@ -101,6 +101,28 @@ func (b *i2cBus) ReadByte(addr byte) (byte, error) {
 	return bytes[0], nil
 }
 
+func (b *i2cBus) ReadBytes(addr byte, num int) ([]byte, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	if err := b.init(); err != nil {
+		return []byte{0}, err
+	}
+
+	if err := b.setAddress(addr); err != nil {
+		return []byte{0}, err
+	}
+
+	bytes := make([]byte, num)
+	n, _ := b.file.Read(bytes)
+
+	if n != num {
+		return []byte{0}, fmt.Errorf("i2c: Unexpected number (%v) of bytes read", n)
+	}
+
+	return bytes, nil
+}
+
 func (b *i2cBus) WriteByte(addr, value byte) error {
 	b.mu.Lock()
 	defer b.mu.Unlock()
diff --git a/i2c.go b/i2c.go
index 8bdb876..d9922ed 100644
--- a/i2c.go
+++ b/i2c.go
@@ -4,6 +4,8 @@ package embd
 
 // I2CBus interface is used to interact with the I2C bus.
 type I2CBus interface {
+	// ReadByte reads a byte from the given address.
+	ReadBytes(addr byte, num int) (value []byte, err error)
 	// ReadByte reads a byte from the given address.
 	ReadByte(addr byte) (value byte, err error)
 	// WriteByte writes a byte to the given address.