linux-kernel - Re: [PATCH v4 03/13] media: pci: cx18-av-vbi: Replace open-coded parity calculation with parity

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Message-ID: <19625cf93f8.279b.9b12b7fc0a3841636cfb5e919b41b954@broadcom.com>
Date: Fri, 11 Apr 2025 19:04:43 +0200
From: Arend Van Spriel <arend.vanspriel@...adcom.com>
To: "Kuan-Wei Chiu" <visitorckw@...il.com>
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	Yu-Chun Lin <eleanor15x@...il.com>
Subject: Re: [PATCH v4 03/13] media: pci: cx18-av-vbi: Replace open-coded parity calculation with parity_odd()

On April 11, 2025 6:37:35 PM Kuan-Wei Chiu <visitorckw@...il.com> wrote:

> On Thu, Apr 10, 2025 at 07:08:58AM +0200, Arend Van Spriel wrote:
>> On April 10, 2025 12:06:52 AM Johannes Berg <johannes@...solutions.net> wrote:
>>
>>> On Wed, 2025-04-09 at 20:43 +0200, Arend van Spriel wrote:
>>>>
>>>> This is orthogonal to the change to parity_odd() though. More specific
>>>> to the new parity_odd() you can now do following as parity_odd()
>>>> argument is u64:
>>>>
>>>> err = !parity_odd(*(u16 *)p);
>>>
>>> Can it though? Need to be careful with alignment with that, I'd think.
>>
>> My bad. You are absolutely right.
> Then maybe we can still go with:
>
> err = !parity_odd(p[0] ^ p[1]);
>
> I believe this should still be a fairly safe approach?

Yes. Or whatever the name will be ;-)

Regards,
Arend