[RFC 0/4] how to link a panel to a touchscreen controller driver

[Martin Kepplinger]

hi,

When there's a panel/touchscreen combination that is sold as a combinded
module (with the reset line shared even), how would I connect the 2
drivers and make sure the touchscreen driver probes after the panel is ready?

I have the feeling there is https://docs.kernel.org/driver-api/device_link.html
for such cases. Can you show me examples of 2 "random" drivers connected
in this case?

In the past I also played with CONFIG_RESET_GPIO using the reset-controller
logic, but I *think* this is more for 2+ of the *same* devices connected.

Might there be yet a different way in devicetree I'm not aware of?

The below patches - for completeness - are only the workaround for what I'd
like to do, exposing the state of the panel so that the touchscreen can query
it.

thank you very much for any hints,

                               martin



Guido Günther (2):
  hack: drm: panel: mantix: Allow to query enabled state
  hack: Input: edt-ft5x06: hackery to probe after panel

Martin Kepplinger (2):
  hack: edt-ft5x06 / panel-mantix-mlaf057we51: declare
    mantix_panel_prepared() in drm_panel.h
  hack: arm64: dts: imx8mq-librem5: add purism,panel-librem5-workaround

 .../boot/dts/freescale/imx8mq-librem5.dtsi    |  1 +
 .../gpu/drm/panel/panel-mantix-mlaf057we51.c  | 12 ++++++++++
 drivers/input/touchscreen/edt-ft5x06.c        | 22 +++++++++++++++++++
 include/drm/drm_panel.h                       |  2 ++
 4 files changed, 37 insertions(+)

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2.47.3