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From: Dan Carpenter <error27@gmail.com>
To: Punnay Sharma <punnaysharma805@gmail.com>
Cc: gregkh@linuxfoundation.org, mchehab@kernel.org,
	linux-media@vger.kernel.org, linux-staging@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] staging: media: av7110: fix corrupted BER reporting in sp8870
Date: Fri, 7 Aug 2026 21:46:35 +0300	[thread overview]
Message-ID: <anYoC44F6SrKW5iC@stanley.mountain> (raw)
In-Reply-To: <20260807183443.13912-1-punnaysharma805@gmail.com>

On Sat, Aug 08, 2026 at 12:04:42AM +0530, Punnay Sharma wrote:
> In sp8870_read_ber(), the 14-bit Bit Error Rate (BER) is assembled by
> reading two I2C registers: 0xC08 (lower 6 bits) and 0xC07 (upper 8 bits).
> 
> The current implementation masks the lower bits via `tmp = ret & 0x3F;`
> but subsequently overwrites `tmp` entirely when processing the upper
> bits using a direct assignment (`tmp = ret << 6;`). This logical error
> causes the lower 6 bits of the BER hardware metric to be silently
> discarded.
> 
> Fix this by using a bitwise OR (`tmp |= ret << 6;`) to correctly merge
> the MSB and LSB payloads before returning the metric to the DVB core.

AI uses a lot of really unnecessary words to say something very simple.
It explains the obvious stuff in detail and ignores the important bits.
It should be something like:

  Checker tools complain that the "tmp = ret & 0x3F;" assignment is
  never used.  It's probably supposed to be ORed.  I don't have the
  hardware so this is untested.

> 
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")

The fact that no one has complained in 21 years, probably means it's
not a real bug.  I generally ignore these ancient things.

> Signed-off-by: Punnay Sharma <punnaysharma805@gmail.com>
> ---

There are a bunch of rules for sending a v2 patch.
https://staticthinking.wordpress.com/2022/07/27/how-to-send-a-v2-patch/

Don't resend the same day.  Add a note to say what changed etc.

regards,
dan carpenter


  parent reply	other threads:[~2026-08-07 18:46 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-07 18:34 [PATCH v2 1/2] staging: media: av7110: fix corrupted BER reporting in sp8870 Punnay Sharma
2026-08-07 18:34 ` [PATCH v2 2/2] staging: media: av7110: fix sp8870 initialization failure state Punnay Sharma
2026-08-07 18:46 ` Dan Carpenter [this message]
2026-08-08  5:45 ` [PATCH v2 1/2] staging: media: av7110: fix corrupted BER reporting in sp8870 Greg KH

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