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mirror of https://github.com/kidoman/embd synced 2024-12-22 12:50:19 +01:00
embd/detect.go
alsm 9401acd013 embd, rpi: determine pi revision, make rev2 pinmap default
added a function to determine the revision of the pi the program is
running on from "Revision" field in /proc/cpuinfo, also made the rev2
gpio pinmap the default
2014-09-09 15:57:27 +01:00

127 lines
2.7 KiB
Go

// Host detection.
package embd
import (
"fmt"
"io/ioutil"
"os/exec"
"strconv"
"strings"
)
// The Host type represents all the supported host types.
type Host string
const (
// HostNull reprents a null host.
HostNull Host = ""
// HostRPi represents the RaspberryPi.
HostRPi = "Raspberry Pi"
// HostBBB represents the BeagleBone Black.
HostBBB = "BeagleBone Black"
// HostGalileo represents the Intel Galileo board.
HostGalileo = "Intel Galileo"
// HostCubieTruck represents the Cubie Truck.
HostCubieTruck = "CubieTruck"
// HostRadxa represents the Radxa board.
HostRadxa = "Radxa"
)
func execOutput(name string, arg ...string) (output string, err error) {
var out []byte
if out, err = exec.Command(name, arg...).Output(); err != nil {
return
}
output = strings.TrimSpace(string(out))
return
}
func nodeName() (string, error) {
return execOutput("uname", "-n")
}
func parseVersion(str string) (major, minor, patch int, err error) {
versionNumber := strings.Split(str, "-")
parts := strings.Split(versionNumber[0], ".")
len := len(parts)
if major, err = strconv.Atoi(parts[0]); err != nil {
return 0, 0, 0, err
}
if minor, err = strconv.Atoi(parts[1]); err != nil {
return 0, 0, 0, err
}
if len > 2 {
part := parts[2]
part = strings.TrimSuffix(part, "+")
if patch, err = strconv.Atoi(part); err != nil {
return 0, 0, 0, err
}
}
return major, minor, patch, err
}
func kernelVersion() (major, minor, patch int, err error) {
output, err := execOutput("uname", "-r")
if err != nil {
return 0, 0, 0, err
}
return parseVersion(output)
}
func getPiRevision() (int, error) {
//default return code of a rev2 board
cpuinfo, err := ioutil.ReadFile("/proc/cpuinfo")
if err != nil {
return 4, err
}
for _, line := range strings.Split(string(cpuinfo), "\n") {
fields := strings.Fields(line)
if len(fields) > 0 && fields[0] == "Revision" {
rev, err := strconv.ParseInt(fields[2], 16, 8)
return int(rev), err
}
}
return 4, nil
}
// DetectHost returns the detected host and its revision number.
func DetectHost() (Host, int, error) {
major, minor, patch, err := kernelVersion()
if err != nil {
return HostNull, 0, err
}
if major < 3 || (major == 3 && minor < 8) {
return HostNull, 0, fmt.Errorf("embd: linux kernel versions lower than 3.8 are not supported. you have %v.%v.%v", major, minor, patch)
}
node, err := nodeName()
if err != nil {
return HostNull, 0, err
}
var host Host
var rev int
switch node {
case "raspberrypi":
host = HostRPi
rev, _ = getPiRevision()
case "beaglebone":
host = HostBBB
default:
return HostNull, 0, fmt.Errorf("embd: your host %q is not supported at this moment. please request support at https://github.com/kidoman/embd/issues", node)
}
return host, rev, nil
}