Allwinner: Implement nanopi neo air (#30)

* Implement nanopi neo air
* Support for PL pins

Co-authored-by: Marc-Antoine Ruel <[email protected]>

AUTHORS

@@ -13,6 +13,7 @@ Google Inc.
 Josh Gardiner
 Matt Aimonetti <[email protected]>
 Max Ekman <[email protected]>
+Peter LoVerso <[email protected]>
 Rifiniti, Inc
 Stephan Sperber
 Thorsten von Eicken <[email protected]>

allwinner/h3.go

@@ -8,6 +8,7 @@
 package allwinner
 
 import (
+	"strconv"
 	"strings"
 
 	"periph.io/x/conn/v3/pin"
@@ -138,16 +139,28 @@ var mappingH3 = map[string][5]pin.Func{
 // code detects a H2+ or H3 processor.
 func mapH3Pins() error {
 	for name, altFuncs := range mappingH3 {
-		pin := cpupins[name]
-		pin.altFunc = altFuncs
-		pin.available = true
-		if strings.Contains(string(altFuncs[4]), "_EINT") ||
-			strings.Contains(string(altFuncs[3]), "_EINT") {
-			pin.supportEdge = true
-		}
+		if strings.HasPrefix(name, "PL") {
+			pinNumStr := name[2:]
+			pinNum, err := strconv.Atoi(pinNumStr)
+			if err != nil {
+				return err
+			}
+			pin := &cpuPinsPL[pinNum]
+			pin.available = true
 
-		// Initializes the sysfs corresponding pin right away.
-		pin.sysfsPin = sysfs.Pins[pin.Number()]
+			// Initializes the sysfs corresponding pin right away.
+			pin.sysfsPin = sysfs.Pins[pin.Number()]
+		} else {
+			pin := cpupins[name]
+			pin.altFunc = altFuncs
+			pin.available = true
+			if strings.Contains(string(altFuncs[4]), "_EINT") ||
+				strings.Contains(string(altFuncs[3]), "_EINT") {
+				pin.supportEdge = true
+			}
+			// Initializes the sysfs corresponding pin right away.
+			pin.sysfsPin = sysfs.Pins[pin.Number()]
+		}
 	}
 	return nil
 }

cpu/cpu.go

@@ -59,7 +59,7 @@ func getMaxSpeedLinux() int64 {
 	if maxSpeed == -1 {
 		maxSpeed = 0
 		if f, err := openFile("/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq", os.O_RDONLY); err == nil {
-			defer f.Close()
+			defer f.Close() //#nosec G307 -- File is opened readonly so errors on file close cannot cause write errors
 			if b, err := io.ReadAll(f); err == nil {
 				s := strings.TrimSpace(string(b))
 				if i, err := strconv.ParseInt(s, 10, 64); err == nil {

nanopi/doc.go

@@ -0,0 +1,10 @@
+// Copyright 2022 The Periph Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+// Package nanopi contains nanoPi hardware logic.
+//
+// Requires armbian jessie server.
+//
+// # Physical
+package nanopi

nanopi/nanopi.go

@@ -0,0 +1,184 @@
+// Copyright 2022 The Periph Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+// nanoPi pin out.
+
+package nanopi
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"periph.io/x/conn/v3/driver/driverreg"
+	"periph.io/x/conn/v3/gpio"
+	"periph.io/x/conn/v3/pin"
+	"periph.io/x/conn/v3/pin/pinreg"
+	"periph.io/x/host/v3/allwinner"
+	"periph.io/x/host/v3/distro"
+)
+
+// Present return true if a NanoPi board is detected.
+func Present() bool {
+	if isArm {
+		// This works for the NanoPi Neo Air, not sure if other NAnoPi boards
+		// match the same DTModel prefix.
+		return strings.HasPrefix(distro.DTModel(), "FriendlyARM")
+	}
+
+	return false
+}
+
+const (
+	boardNeoAir string = "NanoPi NEO Air" // + LTS (H2/H3 have identical pinouts)
+)
+
+var (
+	PA1_1  pin.Pin    = pin.DC_IN // VCC 3v3 Ext
+	PA1_2  pin.Pin    = pin.V5
+	PA1_3  gpio.PinIO = allwinner.PA12
+	PA1_4  pin.Pin    = pin.V5
+	PA1_5  gpio.PinIO = allwinner.PA11
+	PA1_6  pin.Pin    = pin.GROUND
+	PA1_7  gpio.PinIO = allwinner.PG11
+	PA1_8  gpio.PinIO = allwinner.PG6
+	PA1_9  pin.Pin    = pin.GROUND
+	PA1_10 gpio.PinIO = allwinner.PG7
+	PA1_11 gpio.PinIO = allwinner.PA0
+	PA1_12 gpio.PinIO = allwinner.PA6
+	PA1_13 gpio.PinIO = allwinner.PA2
+	PA1_14 pin.Pin    = pin.GROUND
+	PA1_15 gpio.PinIO = allwinner.PA3
+	PA1_16 gpio.PinIO = allwinner.PA8
+	PA1_17 pin.Pin    = pin.DC_IN // VCC 3v3 Ext
+	PA1_18 gpio.PinIO = allwinner.PG9
+	PA1_19 gpio.PinIO = allwinner.PC0
+	PA1_20 pin.Pin    = pin.GROUND
+	PA1_21 gpio.PinIO = allwinner.PC1
+	PA1_22 gpio.PinIO = allwinner.PA1
+	PA1_23 gpio.PinIO = allwinner.PC2
+	PA1_24 gpio.PinIO = allwinner.PC3
+
+	FUN1_1  pin.Pin = pin.V5
+	FUN1_2  pin.Pin = gpio.INVALID   // USB-DP2
+	FUN1_3  pin.Pin = gpio.INVALID   // USB-DM2
+	FUN1_4  pin.Pin = gpio.INVALID   // USB-DP3
+	FUN1_5  pin.Pin = gpio.INVALID   // USB-DM3
+	FUN1_6  pin.Pin = allwinner.PL11 // IR-RX
+	FUN1_7  pin.Pin = allwinner.PA17 // SPDIF-OUT
+	FUN1_8  pin.Pin = allwinner.PA18 // PCM0_SYNC/I2S0_LRC
+	FUN1_9  pin.Pin = allwinner.PA19 // PCM0_CLK/I2S0_BCK
+	FUN1_10 pin.Pin = allwinner.PA20 // PCM0_DOUT/I2S0_SDOUT
+	FUN1_11 pin.Pin = allwinner.PA21 // PCM0_DIN/I2S0_SDIN
+	FUN1_12 pin.Pin = pin.GROUND     //
+
+	FUN2_1 pin.Pin = allwinner.HP_LEFT  // LINEOUTL
+	FUN2_2 pin.Pin = allwinner.HP_RIGHT // LINEOUT
+	FUN2_3 pin.Pin = allwinner.MIC_GND  // MIC GND
+	FUN2_4 pin.Pin = allwinner.MIC_IN   // MIC IN
+
+	FUN3_1 pin.Pin = pin.GROUND
+	FUN3_2 pin.Pin = pin.V5
+	FUN3_3 pin.Pin = allwinner.PA4 // UART TX
+	FUN3_4 pin.Pin = allwinner.PA5 // UART RX
+
+)
+
+// registerHeaders registers the headers for various NanoPi boards. Currently
+// only NanoPi NEO Air is supported.
+func registerHeaders(model string) error {
+	if strings.Contains(model, boardNeoAir) {
+		// 24pin expansion port
+		if err := pinreg.Register("PA", [][]pin.Pin{
+			{PA1_1, PA1_2},
+			{PA1_3, PA1_4},
+			{PA1_5, PA1_6},
+			{PA1_7, PA1_8},
+			{PA1_9, PA1_10},
+			{PA1_11, PA1_12},
+			{PA1_13, PA1_14},
+			{PA1_15, PA1_16},
+			{PA1_17, PA1_18},
+			{PA1_19, PA1_20},
+			{PA1_21, PA1_22},
+			{PA1_23, PA1_24},
+		}); err != nil {
+			return err
+		}
+
+		// 12pin function interface
+		if err := pinreg.Register("FUN", [][]pin.Pin{
+			{FUN1_1},
+			{FUN1_2},
+			{FUN1_3},
+			{FUN1_4},
+			{FUN1_5},
+			{FUN1_6},
+			{FUN1_7},
+			{FUN1_8},
+			{FUN1_9},
+			{FUN1_10},
+			{FUN1_11},
+			{FUN1_12},
+			{FUN2_1},
+			{FUN2_2},
+			{FUN2_3},
+			{FUN2_4},
+			{FUN3_1},
+			{FUN3_2},
+			{FUN3_3},
+			{FUN3_4},
+		}); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// driver implements periph.Driver.
+type driver struct {
+}
+
+// String is the text representation of the board.
+func (d *driver) String() string {
+	return "nanopi"
+}
+
+// Prerequisites load drivers before the actual driver is loaded. For
+// these boards, we do not need any prerequisites.
+func (d *driver) Prerequisites() []string {
+	return nil
+}
+
+// After this driver is loaded, we need to load generic Allwinner drivers
+// for the GPIO pins which are identical on all Allwinner CPUs.
+func (d *driver) After() []string {
+	return []string{"allwinner-gpio", "allwinner-gpio-pl"}
+}
+
+// Init initializes the driver by checking its presence and if found, the
+// driver will be registered.
+func (d *driver) Init() (bool, error) {
+	if !Present() {
+		return false, errors.New("NanoPi board not detected")
+	}
+
+	model := distro.DTModel()
+	if model == "<unknown>" {
+		return true, fmt.Errorf("nanopi: failed to obtain model")
+	}
+
+	err := registerHeaders(model)
+	return true, err
+}
+
+// init register the driver.
+func init() {
+	if isArm {
+		driverreg.MustRegister(&drv)
+	}
+}
+
+var drv driver

nanopi/nanopi_arm.go

@@ -0,0 +1,7 @@
+// Copyright 2022 The Periph Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+package nanopi
+
+const isArm = true

nanopi/nanopi_arm64.go

@@ -0,0 +1,10 @@
+// Copyright 2022 The Periph Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+//go:build arm64
+// +build arm64
+
+package nanopi
+
+const isArm = true

nanopi/nanopi_other.go

@@ -0,0 +1,10 @@
+// Copyright 2022 The Periph Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+//go:build !arm && !arm64
+// +build !arm,!arm64
+
+package nanopi
+
+const isArm = false