Re: [PATCH] media: nxp: imx8-isi: check return value of media_pad_remote_pad_first()

[Martin Kepplinger-Novakovic <martink@posteo.de>]

Am Mittwoch, dem 20.08.2025 um 17:01 +0300 schrieb Laurent Pinchart:
> Hi Martin,
> 
> On Thu, Feb 06, 2025 at 08:49:37AM +0000, Martin Kepplinger wrote:
> > Am Mittwoch, dem 05.02.2025 um 17:29 +0000 schrieb Martin
> > Kepplinger-
> > Novaković:
> > > media_pad_remote_pad_first() return NULL if "no enabled link has
> > > been
> > > found".
> > > Check for that.
> > > 
> > > backstory
> > > =========
> > > While trying to get a (Y10 grey) sensor working on imx8mp
> > > (v6.12.12
> > > now and
> > > I know the hardware works on an ancient nxp-kernel),
> > > I tried to enable the sensor link, set formats and stream:
> > 
> > btw, that's roughly the
> > driver: 
> > https://github.com/VC-MIPI-modules/vc_mipi_nxp/tree/master/src
> > that might need additions to with recent mainline kernels. Will the
> > sensor be the reason for the link not being found here?
> 
> I've submitted
> https://lore.kernel.org/linux-media/20250820140021.8026-1-laurent.pinchart@ideasonboard.com
> ,
> which should fix this issue in a more generic way.
> 


Hi, thank you. As posted over there, this indeed fixes the crash
itself.

P.S.:
Not that you should care :) But as for my specific "vision components"
sensor I want to use here, where this rpi-driver exists:
https://github.com/VC-MIPI-modules/vc_mipi_raspi/blob/main/src/vc_mipi_camera/vc_mipi_camera.c
a script like

media-ctl -d 1 --links "'vc_mipi_camera 3-001a':0->'csis-
32e50000.csi':0[1]"

# format settings for mipi rx and ISI
media-ctl -d "platform:32e00000.isi" --set-v4l2 '"vc_mipi_camera 3-
001a":0[fmt:Y10_1X10/2592x1944 field:none]'
media-ctl -d "platform:32e00000.isi" --set-v4l2 '"csis-
32e50000.csi":0[fmt:Y10_1X10/2592x1944 field:none colorspace:srgb]'
media-ctl -d "platform:32e00000.isi" --set-v4l2
'"crossbar":0[fmt:Y10_1X10/2592x1944 field:none colorspace:srgb]'
media-ctl -d "platform:32e00000.isi" --set-v4l2
'"mxc_isi.0":0[fmt:Y10_1X10/2592x1944 field:none colorspace:srgb]'

v4l2-ctl -d /dev/video2 --set-fmt-
video=width=2592,height=1944,pixelformat='Y10 '
v4l2-ctl --verbose --device=/dev/video2 --stream-mmap --stream-count=10


still fails with


[   34.642252] vc_mipi_camera 3-001a: vc_core_set_format(): Set format:
0x200a (Y10_1X10)
[   34.650227] vc_mipi_camera 3-001a: vc_core_try_format(): Try format
0x200a (Y10_1X10, format: 0x2b)
[   34.659284] vc_mipi_camera 3-001a: vc_core_try_format(): Checking
mode 0 (format: 0x2b)
[   34.667295] vc_mipi_camera 3-001a: vc_core_calculate_max_exposure():
period_1H_ns: 7407, vmax.max: 1048575, vmax.min: 9
[   34.678083] vc_mipi_camera 3-001a: vc_core_get_optimized_vmax():
vmax_def: 4500, v_factor: 0, height: 1944/1944
[   34.688178] vc_mipi_camera 3-001a:
vc_core_calculate_max_frame_rate(): period_1H_ns: 7407, vmax:
4500/4500, max_frame_rate: 30002
[   34.699833] vc_mipi_camera 3-001a: vc_core_update_controls():
num_lanes: 2, format 43, exposure.max: 7766728 us, framerate.max: 30002
mHz
[   34.712184] vc_mipi_camera 3-001a: vc_core_set_frame(): Set frame
(left: 0, top: 0, width: 2592, height: 1944)
[   34.722208] vc_mipi_camera 3-001a: vc_core_calculate_max_exposure():
period_1H_ns: 7407, vmax.max: 1048575, vmax.min: 9
[   34.733000] vc_mipi_camera 3-001a: vc_core_get_optimized_vmax():
vmax_def: 4500, v_factor: 0, height: 1944/1944
[   34.743112] vc_mipi_camera 3-001a:
vc_core_calculate_max_frame_rate(): period_1H_ns: 7407, vmax:
4500/4500, max_frame_rate: 30002
[   34.754768] vc_mipi_camera 3-001a: vc_core_update_controls():
num_lanes: 2, format 43, exposure.max: 7766728 us, framerate.max: 30002
mHz
VIDIOC_QUERYCAP: ok
		VIDIOC_REQBUFS returned 0 (Success)
		VIDIOC_CREATE_BUFS returned 0 (Success)
		VIDIOC_QUERYBUF returned 0 (Success)
		VIDIOC_QUERYBUF returned 0 (Success)
		VIDIOC_QUERYBUF returned 0 (Success)
		VIDIOC_QUERYBUF returned 0 (Success)
		VIDIOC_G_FMT returned 0 (Success)
		VIDIOC_QBUF returned 0 (Success)
		VIDIOC_QBUF returned 0 (Success)
		VIDIOC_QBUF returned 0 (Success)
		VIDIOC_QBUF returned 0 (Success)
		VIDIOC_STREAMON returned -1 (Broken pipe)