linux-kernel - mei: me: unneeded tests in mei_me_hw_ready

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Message-ID: <1388177072.9086.33.camel@x220>
Date:	Fri, 27 Dec 2013 21:44:32 +0100
From:	Paul Bolle <pebolle@...cali.nl>
To:	Tomas Winkler <tomas.winkler@...el.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:	Shuah Khan <shuah.kh@...sung.com>, linux-kernel@...r.kernel.org
Subject: mei: me: unneeded tests in mei_me_hw_ready_wait()

0) mei_me_hw_ready_wait() currently reads:
        int err;
        [...]

        err = wait_event_interruptible_timeout(dev->wait_hw_ready,
                        dev->recvd_hw_ready,
                        mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
        [...]
        if (!err && !dev->recvd_hw_ready) {
                if (!err)
                        err = -ETIMEDOUT;
                dev_err(&dev->pdev->dev,
                        "wait hw ready failed. status = %d\n", err);
                return err;
        }
	[...]

1) The second check for !err was introduced in commit dab9bf41b23f
("mei: me: fix waiting for hw ready"). It's not needed. And the check
for !dev->recvd_hw_ready seems unneeded too.

2) So perhaps something like this was intended:
        [...]
        if (err <= 0) {
                if (!err)
                        err = -ETIMEDOUT;
                dev_err(&dev->pdev->dev,
                        "wait hw ready failed. status = %d\n", err);
                return err;
        }
        [...]

But that's just a guess. For example: it is unclear whether that would
handle wait_event_interruptible_timeout() returning -ERESTARTSYS
correctly. So I'm unable to draft and submit a patch here.


Paul Bolle

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