Fix issues found by misspell, gofmt -s -w, golint and go vet; add badges

- There were several typos
- Simplified a few simplified statements
- Added doc for a few exported symbols
- Fix incorrect printf usage

README.md

@@ -2,6 +2,10 @@
 
 Documentation is at https://periph.io
 
+[![GoDoc](https://godoc.org/periph.io/x/periph?status.svg)](https://godoc.org/periph.io/x/periph)
+[![Go Report
+Card](https://goreportcard.com/badge/periph.io/x/periph)](https://goreportcard.com/report/periph.io/x/periph)
+
 
 ## Sample
 

devices/bme280/bme280.go

@@ -306,7 +306,7 @@ func (d *Dev) writeCommands(b []byte) error {
 // 0xE0        Reset by writing 0xB6 to it
 // 0xE1..0xF0  Calibration data
 // 0xF1        --
-// 0xF2        ctrl_hum; ctrl_meas must be writen to after for change to this register to take effect
+// 0xF2        ctrl_hum; ctrl_meas must be written to after for change to this register to take effect
 // 0xF3        status
 // 0xF4        ctrl_meas
 // 0xF5        config

devices/lirc/lirc.go

@@ -35,7 +35,7 @@ func New() (*Conn, error) {
 		return nil, err
 	}
 	c := &Conn{w: w, c: make(chan ir.Message), list: map[string][]string{}}
-	// Inconditionally retrieve the list of all known keys at start.
+	// Unconditionally retrieve the list of all known keys at start.
 	if _, err := w.Write([]byte("LIST\n")); err != nil {
 		w.Close()
 		return nil, err

experimental/devices/bitbang/i2c.go

@@ -20,7 +20,7 @@ import (
 	"periph.io/x/periph/host/cpu"
 )
 
-// Use SkipAddr to skip the address from being sent.
+// SkipAddr can be used to skip the address from being sent.
 const SkipAddr uint16 = 0xFFFF
 
 // I2C represents an I²C master implemented as bit-banging on 2 GPIO pins.
@@ -53,7 +53,7 @@ func (i *I2C) Tx(addr uint16, w, r []byte) error {
 	if addr != SkipAddr {
 		if addr > 0xFF {
 			// Page 15, section 3.1.11 10-bit addressing
-			// TOOD(maruel): Implement if desired; prefix 0b11110xx.
+			// TODO(maruel): Implement if desired; prefix 0b11110xx.
 			return errors.New("bitbang-i2c: invalid address")
 		}
 		// Page 13, section 3.1.10 The slave address and R/W bit

experimental/devices/ds248x/dev.go

@@ -72,7 +72,7 @@ func (d *Dev) Tx(w, r []byte, power onewire.Pullup) error {
 	}
 
 	// Read bytes from one-wire bus.
-	for i, _ := range r {
+	for i := range r {
 		if power == onewire.StrongPullup && i == len(r)-1 {
 			// This is the last byte, need to activate strong-pull-up
 			d.i2cTx([]byte{cmdWriteConfig, d.confReg&0xbf | 0x4}, nil)

experimental/devices/ds248x/ds248x.go

@@ -24,8 +24,10 @@ import (
 type PupOhm uint8
 
 const (
-	R500Ω  = 4 // 500Ω passive pull-up resistor
-	R1000Ω = 6 // 1000Ω passive pull-up resistor
+	// R500Ω passive pull-up resistor.
+	R500Ω = 4
+	// R1000Ω passive pull-up resistor.
+	R1000Ω = 6
 )
 
 // Opts contains options to pass to the constructor.