linux-kernel - [media] s5p-cec: strange clk enabling pattern

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Message-Id: <1487886098-20557-1-git-send-email-khoroshilov@ispras.ru>
Date:   Fri, 24 Feb 2017 00:41:38 +0300
From:   Alexey Khoroshilov <khoroshilov@...ras.ru>
To:     Kamil Debski <kamil@...as.org>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Hans Verkuil <hans.verkuil@...co.com>,
        Sylwester Nawrocki <s.nawrocki@...sung.com>
Cc:     Alexey Khoroshilov <khoroshilov@...ras.ru>,
        linux-media@...r.kernel.org, devel@...verdev.osuosl.org,
        linux-kernel@...r.kernel.org, ldv-project@...uxtesting.org
Subject: [media] s5p-cec: strange clk enabling pattern

The s5p-cec driver has a few places that touch hdmicec clk:

static int s5p_cec_probe(struct platform_device *pdev)
{
	...
	cec->clk = devm_clk_get(dev, "hdmicec");
	if (IS_ERR(cec->clk))
		return PTR_ERR(cec->clk);
	...
}

static int __maybe_unused s5p_cec_runtime_suspend(struct device *dev)
{
	struct s5p_cec_dev *cec = dev_get_drvdata(dev);

	clk_disable_unprepare(cec->clk);
	return 0;
}

static int __maybe_unused s5p_cec_runtime_resume(struct device *dev)
{
	struct s5p_cec_dev *cec = dev_get_drvdata(dev);
	int ret;

	ret = clk_prepare_enable(cec->clk);
	if (ret < 0)
		return ret;
	return 0;
}

Is it ok to enable/disable clock in rusume/suspend only?
Or have I missed anything?

--
Thank you,
Alexey Khoroshilov
Linux Verification Center, ISPRAS
web: http://linuxtesting.org