[Intel-gfx] [PATCH 01/16] drm/i915: Provide a hook for selftests

[Chris Wilson]

On Thu, Dec 08, 2016 at 10:47:52AM +0000, Tvrtko Ursulin wrote:
> On 07/12/2016 13:58, Chris Wilson wrote:
> >-	return i915_driver_load(pdev, ent);
> >+	err = i915_driver_load(pdev, ent);
> >+	if (err)
> >+		return err;
> >+
> >+	err = i915_late_selftests(pdev);
> >+	if (err) {
> >+		i915_driver_unload(pci_get_drvdata(pdev));
> >+		return err > 0 ? -ENOTTY : err;
> 
> Here ...
> 
> >+	}
> >+
> >+	return 0;
> > }
> >
> > static void i915_pci_remove(struct pci_dev *pdev)
> >@@ -520,6 +532,11 @@ static struct pci_driver i915_pci_driver = {
> > static int __init i915_init(void)
> > {
> > 	bool use_kms = true;
> >+	int err;
> >+
> >+	err = i915_mock_selftests();
> >+	if (err)
> >+		return err > 0 ? 0 : err;
> 
> ... and here, the return conversion is different but in the
> implementation is the same. It is probably wrong or at least
> confusing so it would be good to make it the same.

The return convention is tricky because ->probe and module_init want
different things. To cancel the probe, we have to return an error value
(-ENOTTY). But for integration with kselftest we want the module load to
report success (kselftest effectively uses
	modprobe i915 mock_selftests=-1 || exit "FAIL"
). Our igt_kselftest has access to the error code from the syscall and
so can differentiate better than the kselftest.sh, but that shell script
is the lowest common demoninator
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre