Re: [PATCH 3/6] dt-bindings: connector: Add Toradex camera connector

[Francesco Dolcini]

On Thu, Sep 10, 2026 at 12:01:51PM -0500, Frank Li wrote:
> On Thu, Sep 10, 2026 at 06:39:30PM +0200, Ernest Van Hoecke wrote:
> > Hi Frank,
> >
> > Thanks for reviewing this so quickly.
> >
> > On Thu, Sep 10, 2026 at 11:26:22AM -0500, Frank Li wrote:
> > > On Thu, Sep 10, 2026 at 05:37:59PM +0200, Ernest Van Hoecke wrote:
> > > > From: Ernest Van Hoecke <ernest.vanhoecke@xxxxxxxxxxx>
> > > >
> > > > Toradex boards route the sideband signals of their 24-pin camera
> > > > connectors to different GPIO controllers. Camera overlays which name
> > > > those controllers directly must therefore be duplicated for each host
> > > > board.
> > > >
> > > > Describe reset, power-down, detection and power-control as
> > > > connector-local GPIO functions. This lets an accessory overlay remain
> > > > independent of the host wiring. MIPI CSI-2, I2C, clocks and supplies
> > > > remain described separately because the GPIO nexus does not abstract
> > > > them.
> > > >
> > > > Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@xxxxxxxxxxx>
> > > > ---
> > > >  .../connector/toradex,camera-connector.yaml        | 86 ++++++++++++++++++++++
> > > >  1 file changed, 86 insertions(+)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/connector/toradex,camera-connector.yaml b/Documentation/devicetree/bindings/connector/toradex,camera-connector.yaml
> > > > new file mode 100644
> > > > index 000000000000..06e6836e1aa6
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/connector/toradex,camera-connector.yaml
> > > > @@ -0,0 +1,86 @@
> > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > > +%YAML 1.2
> > > > +---
> > > > +$id: http://devicetree.org/schemas/connector/toradex,camera-connector.yaml#
> > > > +$schema: http://devicetree.org/meta-schemas/base.yaml#
> > > > +
> > > > +title: Toradex camera connector GPIO nexus
> > > > +
> > > > +maintainers:
> > > > +  - Ernest Van Hoecke <ernest.vanhoecke@xxxxxxxxxxx>
> > > > +  - Toradex Linux BSP Team <linux-bsp@xxxxxxxxxxx>
> > > > +
> > > > +description: |
> > > > +  Toradex boards provide 24-pin camera connectors carrying MIPI CSI-2, I2C,
> > > > +  clock, power, and sideband GPIO signals. This binding describes the sideband
> > > > +  signals as a GPIO nexus. The other connector resources remain described by
> > > > +  the surrounding board device tree.
> > > > +
> > > > +  The nexus exposes connector-local GPIO function numbers to camera overlays
> > > > +  and maps the functions wired by a carrier board to their GPIO controllers.
> > > > +  GPIO specifiers contain a function number followed by standard GPIO flags.
> > > > +  A board may omit functions which it does not wire.
> > > > +
> > > > +  The function numbers are:
> > > > +    - 0: Camera reset, connector pin 11
> > > > +    - 1: Camera power-down, connector pin 22
> > > > +    - 2: Camera identification, connector pin 23
> > > > +    - 3: Camera power control, connector pin 24
> > > > +
> > > > +properties:
> > > > +  compatible:
> > > > +    const: toradex,camera-connector
> > >
> > > Name is too generally, suggest use board name, we got similar comments at
> > >
> > > https://lore.kernel.org/imx/20260629074734.3643227-2-chancel.liu@xxxxxxxxxxx/
> >
> > I saw that and it made me reconsider this name.
> >
> > However, I believe that in our case it is specific enough. It is really
> > the same on all our carrier boards, and Toradex specific. It's also only
> > for cameras, which is more defined than just "io". Curious to see if
> > others agree or if we should come up with a name for this.
> 
> If some days later, you update hardware connector to 30pin from 24pins.

That connector is there since years, not days.

We have multiple cameras, designed to mate with it.

If tomorrow we will define a new camera connector (that is absolutely
possible), the new connector will get its name, maybe
toradex,camera-connector-v2, or toradex,camera-connector-22pin or
whatever that connector would be named, not just in the DT, but also as
a product and on the actual HW.


Francesco