Re: [PATCH 2.6.27-rc3] led: driver for LEDs on PCEngines ALIX.2 andALIX.3 boards

From: Constantin Baranov
Date: Sat Aug 23 2008 - 13:12:30 EST


Andrew Morton wrote:
> On Sat, 23 Aug 2008 02:08:15 +0500
> Constantin Baranov <const@xxxxxxxxxxxxxx> wrote:
>
>>> static int alix_led_resume(struct platform_device *dev)
>>> {
>>> int i;
>>> +
>>> for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
>>> led_classdev_resume(&alix_leds[i].cdev);
>>> return 0;
>>> @@ -92,7 +95,7 @@ static int __init alix_led_probe(struct
>>> ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
>>>
>>> if (ret < 0) {
>>> - for (i = i - 2; i >= 0; i--)
>>> + while (--i >= 0)
>>> led_classdev_unregister(&alix_leds[i].cdev);
>>> }
>> At the first iteration this while-loop will attempt to unregister
>> device that has failed and thus is not registered.
>> My for-loop starts from device immediately before failed one.
>
> ug, OK, the complex expression in that for-loop is to blame.
>
> For maintinability we should aim for code which is as simple and as
> straightfroward as possible and which adheres to oft-used and
> well-understood kernel idioms.
>
> For example, this?
>
> static int __init alix_led_probe(struct platform_device *pdev)
> {
> int i;
> int ret;
>
> for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
> ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
> if (ret < 0)
> goto fail;
> }
> return 0;
>
> fail:
> while (--i >= 0)
> led_classdev_unregister(&alix_leds[i].cdev);
> return ret;
> }
>
> (note there's no longer a need for a fake initalisation of `ret')
>
>> Note that probe routine originates from leds-ams-delta.c.
>
> That's what you get for copying stuff :(

Well, this variant looks better and correct and still works.
Should I post again patch or fix-patch?
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