On Wed, May 20, 2026 at 06:10:57PM +0530, Arpit Saini wrote:
> Hi Krzysztof , Dmitry
>
> On 5/19/2026 4:02 PM, Krzysztof Kozlowski wrote:
> > On Mon, May 18, 2026 at 04:34:12PM +0530, Arpit Saini wrote:
> > > ILI7807S is a DSI display controller used to drive MIPI-DSI panels.
> > > The DLC DLC0697 1080x1920 LCD panel is based on this controller.
I can't find this panel on the DLC website. Do you have a pointer to the
product page?
> > >
> > > The panel requires a reset GPIO, backlight enable GPIO, I/O voltage
> >
> > If panel requires it, so should the binding.
> >
> Ack, I will update.
> > ...
> >
> > > + reg:
> > > + maxItems: 1
> > > + description: DSI virtual channel
> > > +
> > > + reset-gpios: true
> > > +
> > > + backlight-en-gpios:
> > > + description: Backlight enable GPIO (active high)
> >
> > What is the name of the pin in ili7807s device?
> >
> Display daughter card has WLED driver as well as LCD bias driver.
What is the display daughter card here? Is it a Qualcomm board or is it
a part of the panel?
Also you wrote a lot of text, but you didn't really answer either of the
quesitons. Is there a GPIO on the panel connector that enables the
backlight? If not, this is some external supply on your (assumingly)
daughter card. And it should be modelled accordingly.
>
> The WLED driver's Enable is coming from WLED_P1_EN and PWM is coming from
> LCD_CABC output of the panel.
>
> DISPLAY0_BACKLIGHT_ENABLE (GPIO 91) of ITP baseband card ==> WLED_P1_EN of
> Display Daughter Card (DC)
>
> In the display daughter card of Shikra ITP platform, we are not using the
> external PWM for WLED driver. But connected the CABC output of the panel to
> the WLED driver. Backlight update is happening using MIPI DCS command which
> is driving the CABC output (i.e., PWM for WLED).
>
> Because of above HW configuration, we need to enable the MIPI DCS brightness
> update on this panel. The below command of dlc0697_init_sequence() is
> enabling this.
> mipi_dsi_dcs_write_seq_multi(dsi_ctx, 0x53, 0x24);
So, this should be then dependent on the presence of the backlight in
the DT. Either it is a panel-internal one, or an external one.
>
>
> After checking this, I realized that this panel can be used without the DCS
> backlight as well when it's using PWM based backlight control.
>
> I can add `has_dcs_backlight` in panel_desc and set it true for dlc0697. I
> will update bindings and add backlight as optional property.
Why? Use backlight property instead. It's already there. Anyway, you
really, really need to describe the panel in the bidings. Not your
daughter card.
>
> Currently "backlight-en" as optional. I will fix the commit text as
> Krzysztof pointed out and update the commit text to get add more clarity.
>
> please let me know if you have any comments.
> > > +
> > > + vddi-supply:
> > > + description: I/O voltage supply (1.8V)
> > > +
> > > + avdd-supply:
> > > + description: Positive LCD bias supply (AVDD), typically +5.5V
> > > + (range 4.5V to 6.3V)
> > > +
> > > + avee-supply:
> > > + description: Negative LCD bias supply (AVEE), typically -5.5V
> > > + (range -6.3V to -4.5V)
> > > +
> > > + port: true
> > > +
> > > +required:
> > > + - compatible
> > > + - reg
> > > + - reset-gpios
> > > + - vddi-supply
> > > + - avdd-supply
> > > + - avee-supply
> > > + - port
> > > +
> > > +additionalProperties: false
> > > +
> > > +examples:
> > > + - |
> > > + #include <dt-bindings/gpio/gpio.h>
> > > +
> > > + dsi {
> > > + #address-cells = <1>;
> > > + #size-cells = <0>;
> > > +
> > > + panel@0 {
> > > + compatible = "dlc,dlc0697", "ilitek,ili7807s";
> > > + reg = <0>;
> > > +
> > > + reset-gpios = <&tlmm 3 GPIO_ACTIVE_LOW>;
> > > + backlight-en-gpios = <&tlmm 91 GPIO_ACTIVE_HIGH>;
> > > +
> > > + vddi-supply = <&pm4125_l15>;
> > > + avdd-supply = <&avdd>;
> > > + avee-supply = <&avee>;
> > > +
> > > + port {
> > > + panel_in: endpoint {
> > > + remote-endpoint = <&dsi0_out>;
> > > + };
> > > + };
> > > + };
> > > + };
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index 26060e51c067..529aed669401 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -7941,6 +7941,13 @@ S: Maintained
> > > F:
> > > Documentation/devicetree/bindings/display/bridge/chipone,icn6211.yaml
> > > F: drivers/gpu/drm/bridge/chipone-icn6211.c
> > > +DRM DRIVER FOR ILITEK ILI7807S DSI PANEL
> > > +M: Arpit Saini <[email protected]>
> > > +S: Maintained
> > > +T: git https://gitlab.freedesktop.org/drm/misc/kernel.git
> >
> > Drop, unless you handle patches for this driver.
> Ack, I will update.
> >
> > > +F:
> > > Documentation/devicetree/bindings/display/panel/ilitek,ili7807s.yaml
> > > +F: drivers/gpu/drm/panel/panel-ilitek-ili7807s.c
> >
> > Drop, no such file at this point.
> Ack, I will update.
> >
> > Best regards,
> > Krzysztof
> >
>
--
With best wishes
Dmitry
