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Date: Mon, 14 Jan 2008 13:13:47 +0100
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Dave Young <hidave.darkstar@gmail.com>
Cc: Greg KH <gregkh@suse.de>, stefanr@s5r6.in-berlin.de,
       James.Bottomley@hansenpartnership.com, a.zummo@towertech.it,
       peterz@infradead.org, cbou@mail.ru, linux-kernel@vger.kernel.org,
       David Brownell <david-b@pacbell.net>, krh@redhat.com,
       stern@rowland.harvard.edu, dwmw2@infradead.org, davem@davemloft.net,
       jarkao2@gmail.com
Subject: Re: [PATCH 1/7] driver-core : add class iteration api
Message-ID: <20080114131347.6ddd036a@gondolin.boeblingen.de.ibm.com>
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On Sat, 12 Jan 2008 17:47:54 +0800,
Dave Young <hidave.darkstar@gmail.com> wrote:

Minor style suggestion (same for class_find_child):

> +struct device *class_find_device(struct class *class, void *data,
> +				   int (*match)(struct device *, void *))
> +{
> +	struct device *dev;
> +	int error = 1;

How about using inverse logic here (e.g., start with int found = 0)...

> +
> +	if (!class)
> +		return NULL;
> +
> +	down(&class->sem);
> +	list_for_each_entry(dev, &class->devices, node) {
> +		dev = get_device(dev);
> +		if (dev) {
> +			if (match(dev, data)) {
> +				error = 0;

...and set found = 1 here...

> +				break;
> +			} else
> +				put_device(dev);
> +		} else
> +			break;
> +	}
> +	up(&class->sem);
> +
> +	if (error)
> +		return NULL;
> +	return dev;

...and do
	return found ? dev : NULL;
in the end?

Especially since not finding the device is not really an error.

> +}

Otherwise this looks fine to me.