jetson(PWM): fix set period

[Jwen98]

Solved issues and/or description of the change

changed so the SetPeriod uses the value from the parameter
...

Manual test

• OS and Version (Win/Mac/Linux):
• Adaptor(s) and/or driver(s):
  ...

Checklist

• The PR's target branch is 'hybridgroup:dev'
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes (e.g. by run make test)
• No linter errors exist locally (e.g. by run make fmt_check)
• I have performed a self-review of my own code

If this is a new driver or adaptor:

• I have added the name to the corresponding README.md
• I have added an example to see how to setup and use it
• I have checked or build at least my new example (e.g. by run make examples_check)

If this is a PR for release:

• The PR's target branch is 'hybridgroup:release'
• I have adjusted the CHANGELOG.md (or already prepared and will be merged as soon as possible)

[gen2thomas]

Hi @Jwen98 , thanks for finding this issue and providing a fix. Please read our contributing guide, the target branch needs to be "hybridgroup:dev".

Please can you change the related test file "pwm_pin_test.go" to this content, to test all paths and switch to testify package according to #960 :

Without your fix it will fail.

package jetson

import (
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"gobot.io/x/gobot/v2"
	"gobot.io/x/gobot/v2/system"
)

var _ gobot.PWMPinner = (*PWMPin)(nil)

func TestPwmPin(t *testing.T) {
	a := system.NewAccesser()
	const (
		exportPath    = "/sys/class/pwm/pwmchip0/export"
		unexportPath  = "/sys/class/pwm/pwmchip0/unexport"
		enablePath    = "/sys/class/pwm/pwmchip0/pwm3/enable"
		periodPath    = "/sys/class/pwm/pwmchip0/pwm3/period"
		dutyCyclePath = "/sys/class/pwm/pwmchip0/pwm3/duty_cycle"
	)
	mockPaths := []string{
		exportPath,
		unexportPath,
		enablePath,
		periodPath,
		dutyCyclePath,
	}
	fs := a.UseMockFilesystem(mockPaths)

	pin := NewPWMPin(a, "/sys/class/pwm/pwmchip0", "3")
	require.Equal(t, "", fs.Files[exportPath].Contents)
	require.Equal(t, "", fs.Files[unexportPath].Contents)
	require.Equal(t, "", fs.Files[enablePath].Contents)
	require.Equal(t, "", fs.Files[periodPath].Contents)
	require.Equal(t, "", fs.Files[dutyCyclePath].Contents)

	assert.Nil(t, pin.Export())
	assert.Equal(t, "3", fs.Files[exportPath].Contents)

	assert.Nil(t, pin.SetEnabled(true))
	assert.Equal(t, "1", fs.Files[enablePath].Contents)

	val, _ := pin.Polarity()
	assert.True(t, val)
	assert.Nil(t, pin.SetPolarity(false))
	val, _ = pin.Polarity()
	assert.True(t, val)

	_, err := pin.Period()
	assert.Error(t, err, "Jetson PWM pin period not set")
	assert.Error(t, pin.SetDutyCycle(10000), "Jetson PWM pin period not set")
	assert.Equal(t, "", fs.Files[dutyCyclePath].Contents)

	assert.Nil(t, pin.SetPeriod(20000000))
	assert.Equal(t, "20000000", fs.Files[periodPath].Contents)
	period, _ := pin.Period()
	assert.Equal(t, uint32(20000000), period)
	assert.Error(t, pin.SetPeriod(10000000), "Cannot set the period of individual PWM pins on Jetson")
	assert.Equal(t, "20000000", fs.Files[periodPath].Contents)

	dc, _ := pin.DutyCycle()
	assert.Equal(t, uint32(0), dc)

	assert.Nil(t, pin.SetDutyCycle(10000))
	assert.Equal(t, "10000", fs.Files[dutyCyclePath].Contents)
	dc, _ = pin.DutyCycle()
	assert.Equal(t, uint32(10000), dc)

	assert.Error(t, pin.SetDutyCycle(999999999), "Duty cycle exceeds period")
	dc, _ = pin.DutyCycle()
	assert.Equal(t, "10000", fs.Files[dutyCyclePath].Contents)
	assert.Equal(t, uint32(10000), dc)

	assert.Nil(t, pin.Unexport())
	assert.Equal(t, "3", fs.Files[unexportPath].Contents)
}

[gen2thomas]

Hi @Jwen98 , because I plan to release in the next few days, I set this PR to draft and create a new one to fix this issue for the next release.

Thanks again for finding this issue and your work.
Thomas

[gen2thomas]

done with #1019