linux-kernel - checkpatch: false positives for else after return

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Message-ID: <20160718112622.GA18547@ulmo.ba.sec>
Date:	Mon, 18 Jul 2016 13:26:22 +0200
From:	Thierry Reding <thierry.reding@...il.com>
To:	Andy Whitcroft <apw@...onical.com>, Joe Perches <joe@...ches.com>
Cc:	linux-kernel@...r.kernel.org
Subject: checkpatch: false positives for else after return

Hi,

I've run across what I think is a false positive for checkpatch's
UNNECESSARY_ELSE check. The code that triggers it is in the
tegra_sor_probe() function in drivers/gpu/drm/tegra/sor.c. For
reference, here's the code:

	if (sor->soc->supports_hdmi) {
		sor->ops = &tegra_sor_hdmi_ops;
	} else if (sor->soc->supports_lvds) {
		dev_err(&pdev->dev, "LVDS not supported yet\n");
		return -ENODEV;
	} else {
		dev_err(&pdev->dev, "unknown (non-DP) support\n");
		return -ENODEV;
	}

For the first case (HDMI supported on SoC) the code should continue
normally, but otherwise we need to error out because we don't support
the configuration.

I can't come up with an alternative way of writing the above, and at the
same time I can't see what's wrong with the above. It looks like a
legitimate use of an else to me.

I made an attempt at fixing the check myself but failed miserably. Regex
isn't among my strong skills =\

Any ideas on how to deal with this?

Thanks,
Thierry

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