Re: [PATCH 1/1] arm64: dts: ti: k3-am69-aquila: Add Toradex DSI to LVDS adapter with the 10.1" V2 display

[Leonardo Costa]

On Tue, Sep 08, 2026 at 08:17:57AM -0300, Leonardo Costa wrote:
> Hi Udit,
> 
> On Sun, Sep 06, 2026 at 10:49:52AM +0530, Kumar, Udit wrote:
> > Hi Leonardo
> > 
> > On 8/3/2026 11:04 PM, Leonardo Costa wrote:
> > > From: Leonardo Costa <leonardo.costa@xxxxxxxxxxx>
> > > 
> > > Add a device tree overlay for the Toradex DSI to LVDS Adapter with the
> > > Toradex Capacitive Touch Display 10.1" LVDS V2. The adapter connects to the
> > > Aquila DSI_1 interface. It is based on the Texas Instruments SN65DSI84
> > > DSI-to-LVDS bridge and drives an Opto Logic SCX1001511GGC49 10.1" WXGA TFT
> > > LCD LVDS panel. Touch input is provided by an ILITEK ILI251x capacitive
> > > touch controller.
> > > 
> > > Link: https://developer.toradex.com/hardware/accessories/add-ons/dsi-lvds-adapter
> > > Link: https://developer.toradex.com/hardware/accessories/displays/capacitive-touch-display-101inch-lvds
> > > Signed-off-by: Leonardo Costa <leonardo.costa@xxxxxxxxxxx>
> > > ---
> > >  arch/arm64/boot/dts/ti/Makefile               |   5 +
> > >  ...dsi-to-lvds-v2-panel-cap-touch-10inch.dtso | 153 ++++++++++++++++++
> > >  2 files changed, 158 insertions(+)
> > >  create mode 100644 arch/arm64/boot/dts/ti/k3-am69-aquila-dsi-to-lvds-v2-panel-cap-touch-10inch.dtso
> > > 
> > > diff --git a/arch/arm64/boot/dts/ti/Makefile b/arch/arm64/boot/dts/ti/Makefile
> > > index f4d109ef6798a..8a59fc597aede 100644
> > > --- a/arch/arm64/boot/dts/ti/Makefile
> > > +++ b/arch/arm64/boot/dts/ti/Makefile
> > > @@ -218,6 +218,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am69-aquila-dev.dtb
> > > [..]
> > > +
> > > +	panel-lvds-bridge {
> > > +		compatible = "optologic,scx1001511ggc49", "panel-lvds";
> > 
> > > +		backlight = <&backlight_pwm3>;
> > > +		data-mapping = "vesa-24";
> > > +		height-mm = <136>;
> > > +		width-mm = <217>;
> > > +
> > > +		panel-timing {
> > > +			clock-frequency = <70000000>;
> > 
> > Looking at
> > https://lore.kernel.org/linux-arm-kernel/20260623195741.495734-1-leoreis.costa@xxxxxxxxx/T/#mc4ed25e5253da6dc635fd3eddc317dac8f447f3e
> > 
> > 
> > you are using three different clock-freq 69500000, 64500000 and
> > 70000000 here.
> > Could add some comment here, why freq is adjusted.
> 
> It's for the same reason as the 69500000 clock frequency in the Verdin
> AM62 patch. In general the DSI to LVDS bridge requires longer horizontal
> porch and sync values than the typical values for the display, and we
> intend to use the values on this patch in the general case when the
> bridge is used. The reason why the frequency here (70000000) is
> different from the Verdin AM62 one (69500000) is because we found that
> that 70000000, along with the other timing values, work more
> consistently with the bridge across our modules, the ones on the Verdin
> AM62 ended up being a first iteration.
> 
> I'll add a comment explaining the difference from the native LVDS values
> in the v2 patch.

Correcting my last reply:

The 69500000 frequency and other timings were used on Verdin AM62 were
due to the DPI->DSI bridge used on the module, not only due to the DSI
to LVDS bridge that can be attached to the carrier boards. Ever since
that, we found that the DSI to LVDS bridge itself generally also needs
higher values to work consistently across our modules, compared to the
ones typical for the display.