Re: [PATCH v2 5/5] media: iris: Fix frame interval enumeration for non-divisor framerates

From: Krzysztof Kozlowski

Date: Wed Aug 19 2026 - 03:18:10 EST


On Tue, Aug 18, 2026 at 09:24:18PM +0530, Vishnu Reddy wrote:
> iris_enum_frameintervals() advertised frame intervals using
> V4L2_FRMIVAL_TYPE_STEPWISE with step=1/MAXIMUM_FPS where MAXIMUM_FPS
> is 480. This caused client to enumerate only framerates of the form
> MAXIMUM_FPS/n (where n is a positive integer), restricting support to
> exact divisors of MAXIMUM_FPS (e.g., 480, 240, 160, 120, 96, 80, 60,
> 30, 24, 1).
>
> Framerates that are not exact divisors of MAXIMUM_FPS, such as 29 fps,
> 25 fps, were excluded from the enumerated list. There is no hardware
> restriction to framerates that are exact divisors of MAXIMUM_FPS. This
> caused GStreamer caps negotiation to fail with an "internal data
> stream error" when encoding content at such framerates.
>
> Fix this by using V4L2_FRMIVAL_TYPE_CONTINUOUS. With CONTINUOUS type,
> GStreamer creates a continuous framerate range [1, max_fps], allowing
> any integer framerate within the range to pass caps negotiation. The
> step field is set to 1/1 as required by the V4L2 specification for
> continuous frame intervals.
>
> Fixes: a6882431a138 ("media: iris: Add support for ENUM_FRAMESIZES/FRAMEINTERVALS for encoder")
> Cc: stable@xxxxxxxxxxxxxxx

Why is driver patch AFTER the dts? What is the dependency?

Dependency on DTS is in general a no go. I looked at cover letter and
could not find explanation - where is it?

Please read both submitting patches documents.

Best regards,
Krzysztof