Re: [PATCH 6/8] arm64: dts: freescale: imx8mm-verdin: Add Toradex OV5640 CSI Cameras

[Kieran Bingham <kieran.bingham@ideasonboard.com>]

Quoting Ernest Van Hoecke (2026-07-22 10:27:32)
> On Mon, Jul 20, 2026 at 02:16:46PM -0400, Frank Li wrote:
> > On Mon, Jul 13, 2026 at 05:06:27PM +0200, Ernest Van Hoecke wrote:
> > > From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
> > >
> > > Add device tree overlays for the Toradex OV5640 CSI Camera on Verdin CSI_1.
> > >
> > > The default overlay describes the current CSI Camera Set 5MP OV5640 with a
> > > 27 MHz on-board oscillator. Add a separate 24 MHz overlay for the legacy
> > > camera module.
> > >
> > > Link: https://developer.toradex.com/hardware/accessories/cameras/csi-camera-module-5mp-ov5640-arducam
> > > Link: https://www.toradex.com/accessories/csi-camera-ov5640
> > > Link: https://developer.toradex.com/hardware/legacy-products/other/csi-camera-module-5mp-ov5640/
> > > Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
> > > ---
> > >  arch/arm64/boot/dts/freescale/Makefile             |  6 ++
> > >  .../dts/freescale/imx8mm-verdin-ov5640-24mhz.dtso  | 17 +++++
> > >  .../boot/dts/freescale/imx8mm-verdin-ov5640.dtsi   | 78 ++++++++++++++++++++++
> > >  .../boot/dts/freescale/imx8mm-verdin-ov5640.dtso   | 18 +++++
> > >  4 files changed, 119 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/freescale/Makefile b/arch/arm64/boot/dts/freescale/Makefile
> > > index c465aa19e526..ed3d678e7c5e 100644
> > > --- a/arch/arm64/boot/dts/freescale/Makefile
> > > +++ b/arch/arm64/boot/dts/freescale/Makefile
> > > @@ -189,6 +189,8 @@ dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-nonwifi-mallow.dtb
> > >  dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-nonwifi-yavia-dsi-to-hdmi.dtb
> > >  dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-nonwifi-yavia.dtb
> > >  dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-nonwifi-zinnia.dtb
> > > +dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-ov5640-24mhz.dtbo
> > > +dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-ov5640.dtbo
> > 
> > Need not add dtbo here,
> > 
> > +dtb-$(CONFIG_ARCH_MXC) += imx8mm-verdin-wifi-dev-ov5640-24mhz.dtb can
> > auto dtbo build dtbo.
> > 
> > check other dtbo.
> > 
> > Frank
> > 
> 
> Hi Frank,
> 
> Thanks for the review.
> 
> Our desire is that these dtbo's are standalone targets that are shipped
> for runtime overlay application. Users might, on dev boards especially,
> want to enable or disable any combination of these overlays, and change
> the combination between boots.
> 
> The combined dtb targets validate the overlay and in some listed cases,
> provide a ready-to-use combo. They are not intended to cover all
> possible use-cases.
> 
> My understanding is that indeed a dtb-y targeting a combined DTB will
> build the prerequisite dtbo, but it would not be an install target.

I think with the Toradex ecosystem there would be some value in
supporting or helping with the ongoing dt-connectors or dt-addons topics
so that we can abstract the hardware which is being 'added'.

I think it's important that we tackle the problem of combinatorial
explosions of overlays when we can add a component to multiple
platforms.

For example, your OV5640 camera could be added to many different boards
- and each board could have many different cameras - in different ports.

We should not be copy/pasting overlays for each combination, or we'll
have 'thousands' of identical overlays.

--
Kieran


> 
> Kind regards,
> Ernest
>