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

From: Krzysztof Kozlowski

Date: Mon Jul 06 2026 - 08:25:51 EST


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@xxxxxxxxxxxxxxxx>
> ---
> .../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