Fix lint errors

mcp23xxx/doc.go

@@ -3,7 +3,7 @@
 // that can be found in the LICENSE file.
 
 // Package mcp23xxx provides drivers for the MCP23XXX family of GPIO expanders.
-// It's availble with either I2C or SPI interfaces in 8 and 16 bit variants.
+// It's available with either I2C or SPI interfaces in 8 and 16 bit variants.
 // Additionally, variants are available that have Open-Drain outputs.
 //
 // # Datasheet

mcp23xxx/group.go

@@ -115,6 +115,9 @@ func (pg *pinGroup) Out(value, mask gpio.GPIOValue) error {
 
 	// Read the current value
 	currentValue, err := port.olat.readValue(true)
+	if err != nil {
+		return err
+	}
 	// Apply the mask to clear bits we're writing.
 	currentValue &= (0xff ^ wrMask)
 	// Or the value with the bits to modify

mcp23xxx/group_test.go

@@ -98,9 +98,7 @@ func TestReadWrite(t *testing.T) {
 
 	// For this test, write to the pins individually, and then
 	// confirm read on the other set works as expected.
-	x := gRead
 	gRead = gOut
-	gOut = x
 	t.Log(gRead)
 	pinset := extender.Pins[0][:4]
 	for i := range gpio.GPIOValue(16) {