linux-kernel - Re: [PATCH 2/9] drivers/acpi/asus

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Message-ID: <47C5ABFB.3050607@googlemail.com>
Date:	Wed, 27 Feb 2008 19:29:15 +0100
From:	Mark Pearson <devnull.port@...glemail.com>
To:	Karol Kozimor <sziwan@...l.org.pl>
CC:	Julia Lawall <julia@...u.dk>, corentincj@...aif.net,
	sziwan@...rs.sourceforge.net, acpi4asus-user@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: Re: [PATCH 2/9] drivers/acpi/asus_acpi.c: Correct use of ! and &

Karol Kozimor wrote:
> On 26-02-2008, at 21:42, Julia Lawall wrote:
>>      if (invert)        /* invert target value */
>> -        led_out = !led_out & 0x1;
>> +        led_out = !(led_out & 0x1);
>>
>>      if (!write_acpi_int(hotk->handle, ledname, led_out, NULL))
>>          printk(KERN_WARNING "Asus ACPI: LED (%s) write failed\n",
> 
> 
> IIRC we're just supposed to flip the last bit here, so the original code
> is correct.
> Best regards,
> 

Seems an odd way of doing:

	led_out ^= 0x01;

It this due to some optimisation?

Cheers, Mark.
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