Re: [PATCH v4 5/5] media: qcom: jpeg: Add Qualcomm JPEG V4L2 encoder

[Krzysztof Kozlowski <krzk@kernel.org>]

On 06/07/2026 09:11, Atanas Filipov wrote:
> Add a Qualcomm JPEG encoder driver implemented on top of the
> V4L2 mem2mem framework.
> 
> The driver wires vb2 queue handling, format negotiation, JPEG header
> handling, interrupt-driven job completion, and runtime PM/clock/ICC
> integration for the standalone JPEG encode hardware block.
> 
> This series targets SM8250 (Kona) platforms.
> 
> The jpeg-encoder node is described as a child node of the CAMSS block
> and is probed automatically via of_platform_populate() in camss_probe().
> 
> Usage examples:
> 
> - Check of related video node: v4l2-ctl --list-devices
>   The expected result:
>    qcom-jpeg-enc (platform:qcom-jpeg-enc):
>         /dev/videoX
> 
> V4L2 Examples:
> 
> v4l2-ctl -d /dev/video14 \
> --set-fmt-video-out=width=1920,height=1080,pixelformat=NM12 \
> --stream-mmap --stream-out-mmap
> 
> v4l2-ctl -d /dev/video14 \
> -c compression_quality=100 \
> --set-fmt-video-out=width=1920,height=1080,pixelformat=NM12 \
> --stream-mmap --stream-out-mmap \
> --stream-count=100
> 
> v4l2-ctl -d /dev/video14 \
> --set-fmt-video-out=width=1920,height=1080,pixelformat=NM12 \
> --stream-mmap --stream-out-mmap \
> --set-ctrl=perf_level_auto=1 \
> --set-ctrl=fps_target=30 \
> --stream-count=100
> 
> v4l2-ctl -d /dev/video14 \
> --set-fmt-video-out=width=8192,height=8192,pixelformat=NM12 \
> --stream-mmap --stream-out-mmap \
> --stream-count=1 \
> --stream-to=8192x8192_NM12.jpg
> 
> v4l2-ctl -d /dev/video14 \
> --set-fmt-video-out=width=8192,height=8192,pixelformat=GREY \
> --stream-mmap --stream-out-mmap \
> --stream-count=1 \
> --stream-to=OUT_8192x8192.jpg
> 
> v4l2-ctl -d /dev/video14 \
> -c compression_quality=100 \
> --set-fmt-video-out=width=1920,height=1088,pixelformat=NM12 \
> --stream-mmap=4 --stream-out-mmap=4 \
> --stream-count=100 \
> --stream-out-pattern=21 \
> --stream-to=OUT_1920x1088_100F.mjpg
> 
> GStreamer examples:
> 
> gst-launch-1.0 videotestsrc \
> is-live=false pattern=ball num-buffers=50 ! \
> video/x-raw,format=NV12,width=1920,height=1080 ! \
> videoscale ! videoconvert ! \
> video/x-raw,format=NV12,width=1920,height=1088 ! \
> v4l2jpegenc ! \
> fakesink sync=false
> 
> gst-launch-1.0 videotestsrc is-live=true pattern=smpte ! \
> video/x-raw,format=NV12,width=1920,height=1088 ! \
> v4l2jpegenc extra-controls="controls,compression_quality=85" ! \
> fpsdisplaysink -v sync=false
> 
> Performance measurements on SM8250
> (NV12, quality=100, GStreamer v4l2jpegenc vs jpegenc):
> 
> +------------+-----------------------------+-------------------+
> | Resolution |    HW v4l2jpegenc (q100)    | SW jpegenc (q100) |
> |            | Execution | avrFPS | maxFPS | Execution |  FPS  |
> +------------+-----------+--------+--------+-----------+-------+
> |   512x512  | 2.2332    | 1139.1 | 1195.4 | 7.1055    | 358.0 |
> |  1280x720  | 1.7300    |  418.5 |  457.2 | 5.0585    | 143.1 |
> | 1024x1024  | 1.6991    |  374.3 |  397.4 | 4.7304    | 134.4 |
> | 1920x1088  | 1.6596    |  192.8 |  193.8 | 3.7913    |  84.4 |
> | 2048x2048  | 1.7277    |   92.0 |   91.6 | 3.6343    |  43.7 |
> | 4096x4096  | 1.5887    |   25.2 |   25.3 | 4.2163    |   9.5 |
> | 8192x8192  | 1.3104    |    7.6 |    8.0 | 2.9987    |   3.3 |
> +------------+-----------+--------+--------+-----------+-------+
> 
> Signed-off-by: Atanas Filipov <atanas.filipov@oss.qualcomm.com>
> ---
>  .../bindings/media/qcom,jpeg-encoder.yaml     |  143 +-


NAK


...


> diff --git a/drivers/media/platform/qcom/Kconfig b/drivers/media/platform/qcom/Kconfig
> index 4f4d3a68e6e5..f33d53a754a0 100644
> --- a/drivers/media/platform/qcom/Kconfig
> +++ b/drivers/media/platform/qcom/Kconfig
> @@ -5,3 +5,4 @@ comment "Qualcomm media platform drivers"
>  source "drivers/media/platform/qcom/camss/Kconfig"
>  source "drivers/media/platform/qcom/iris/Kconfig"
>  source "drivers/media/platform/qcom/venus/Kconfig"
> +source "drivers/media/platform/qcom/jpeg/Kconfig"

Just like for other patch, you ignored reviewers' feedback.

I already asked you to go through previous comments around v3. I do not
see improvements, so I assume you do it deliberately.

NAK

Best regards,
Krzysztof