First implementation

vendor/periph.io/x/periph/host/am335x/am335x.go

@@ -0,0 +1,52 @@
+// Copyright 2017 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 am335x
+
+import (
+	"errors"
+	"strings"
+
+	"periph.io/x/periph"
+	"periph.io/x/periph/host/distro"
+)
+
+// Present returns true if a TM AM335x processor is detected.
+func Present() bool {
+	if isArm {
+		return strings.HasPrefix(distro.DTModel(), "TI AM335x")
+	}
+	return false
+}
+
+// driver implements periph.Driver.
+type driver struct {
+}
+
+func (d *driver) String() string {
+	return "am335x"
+}
+
+func (d *driver) Prerequisites() []string {
+	return nil
+}
+
+func (d *driver) After() []string {
+	return nil
+}
+
+func (d *driver) Init() (bool, error) {
+	if !Present() {
+		return false, errors.New("am335x CPU not detected")
+	}
+	return true, nil
+}
+
+func init() {
+	if isArm {
+		periph.MustRegister(&drv)
+	}
+}
+
+var drv driver

vendor/periph.io/x/periph/host/am335x/am335x_arm.go

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+// Copyright 2017 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 am335x
+
+const isArm = true

vendor/periph.io/x/periph/host/am335x/am335x_other.go

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+// Copyright 2017 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.
+
+// +build !arm
+
+package am335x
+
+const isArm = false

vendor/periph.io/x/periph/host/am335x/doc.go

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+// Copyright 2017 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 am335x exposes functionality for the Texas Instruments Sitara AM335x
+// processor family.
+//
+// This processor family is found on the BeagleBone. PRU-ICSS functionality is
+// implemented in package pru.
+//
+// The GPIO pins of the AM335x CPU are grouped into 3 groups of 32 pins: GPIO0,
+// GPIO1, and GPIO2. The CPU documentation refers to GPIO in the form of
+// GPIOx_y. To get the absolute number, as exposed by sysfs, use 32*x+y to get
+// the absolute number.
+//
+// Datasheet
+//
+// Technical Reference Manual
+// https://www.ti.com/lit/ug/spruh73p/spruh73p.pdf
+//
+// Other
+//
+// Marketing page
+// https://www.ti.com/processors/sitara/arm-cortex-a8/am335x/overview.html
+//
+// Family overview
+// https://www.ti.com/lit/ds/symlink/am3359.pdf
+package am335x