spi-device/test/options.js

SPI serial bus access with Node.js

'use strict';

const spi = require('bindings')('spi');
const assert = require('assert');

const device = spi.open(0, 0, err => {
  assert(!err, 'can\'t open device');

  device.getOptions((err, originalOptions) => {
    assert(!err, 'can\'t get original options');

    const options = {
      mode: spi.MODE3,
      // The semantics of chipSelectHigh have changed in kernel 5 and higher
      //chipSelectHigh: true,
      lsbFirst: false,
      threeWire: true,
      loopback: false,
      noChipSelect: true,
      ready: false,
      bitsPerWord: 8,
      maxSpeedHz: originalOptions.maxSpeedHz + 1e4
    };

    device.setOptions(options, err => {
      assert(!err, 'can\'t set options');

      device.getOptions((err, newOptions) => {
        assert(!err, 'can\'t get new options');

        assert.strictEqual(
          options.mode,
          newOptions.mode,
          'can\'t set mode'
        );

        // The semantics of chipSelectHigh have changed in kernel 5 and higher
        //assert.strictEqual(
        //  options.chipSelectHigh,
        //  newOptions.chipSelectHigh,
        //  'can\'t set chipSelectHigh'
        //);

        assert.strictEqual(
          options.lsbFirst,
          newOptions.lsbFirst,
          'can\'t set lsbFirst'
        );

        assert.strictEqual(
          options.threeWire,
          newOptions.threeWire,
          'can\'t set threeWire'
        );

        assert.strictEqual(
          options.loopback,
          newOptions.loopback,
          'can\'t set loopback'
        );

        assert.strictEqual(
          options.noChipSelect,
          newOptions.noChipSelect,
          'can\'t set noChipSelect'
        );

        assert.strictEqual(
          options.ready,
          newOptions.ready,
          'can\'t set ready'
        );

        assert.strictEqual(
          options.bitsPerWord,
          newOptions.bitsPerWord,
          'can\'t set bitsPerWord'
        );

        assert.strictEqual(
          options.maxSpeedHz,
          newOptions.maxSpeedHz,
          'can\'t set maxSpeedHz'
        );

        device.setOptions(originalOptions, err => {
          assert(!err, 'can\'t set options');
        });
      });
    });
  });
});