Re: [PATCH v2 1/2] staging: media: av7110: fix corrupted BER reporting in sp8870
From: Dan Carpenter
Date: Fri Aug 07 2026 - 14:47:51 EST
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@xxxxxxxxx>
> ---
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