Re: [PATCH 0/9] drm/panel and i2c-hid: Allow panels and touchscreens to power sequence together

[Konrad Dybcio <konrad.dybcio@linaro.org>]

On 23.05.2023 21:27, Douglas Anderson wrote:
> 
> The big motivation for this patch series is mostly described in the patch
> ("drm/panel: Add a way for other devices to follow panel state"), but to
> quickly summarize here: for touchscreens that are connected to a panel we
> need the ability to power sequence the two device together. This is not a
> new need, but so far we've managed to get by through a combination of
> inefficiency, added costs, or perhaps just a little bit of brokenness.
> It's time to do better. This patch series allows us to do better.
Panels with integrated touchscreens have been shipping in mainstream devices
since at least 2016. Thanks a lot for looking into this!

Konrad
> 
> Assuming that people think this patch series looks OK, we'll have to
> figure out the right way to land it. The panel patches and i2c-hid
> patches will go through very different trees and so either we'll need
> an Ack from one side or the other or someone to create a tag for the
> other tree to pull in. This will _probably_ require the true drm-misc
> maintainers to get involved, not a lowly committer. ;-)
> 
> 
> Douglas Anderson (9):
>   dt-bindings: HID: i2c-hid: Add "panel" property to i2c-hid backed
>     panels
>   drm/panel: Check for already prepared/enabled in drm_panel
>   drm/panel: Add a way for other devices to follow panel state
>   HID: i2c-hid: Switch to SYSTEM_SLEEP_PM_OPS()
>   HID: i2c-hid: Rearrange probe() to power things up later
>   HID: i2c-hid: Make suspend and resume into helper functions
>   HID: i2c-hid: Support being a panel follower
>   HID: i2c-hid: Do panel follower work on the system_wq
>   arm64: dts: qcom: sc7180: Link trogdor touchscreens to the panels
> 
>  .../bindings/input/elan,ekth6915.yaml         |   6 +
>  .../bindings/input/goodix,gt7375p.yaml        |   6 +
>  .../bindings/input/hid-over-i2c.yaml          |   6 +
>  .../boot/dts/qcom/sc7180-trogdor-coachz.dtsi  |   1 +
>  .../dts/qcom/sc7180-trogdor-homestar.dtsi     |   1 +
>  .../boot/dts/qcom/sc7180-trogdor-lazor.dtsi   |   1 +
>  .../boot/dts/qcom/sc7180-trogdor-pompom.dtsi  |   1 +
>  .../qcom/sc7180-trogdor-quackingstick.dtsi    |   1 +
>  .../dts/qcom/sc7180-trogdor-wormdingler.dtsi  |   1 +
>  drivers/gpu/drm/drm_panel.c                   | 194 +++++++++-
>  drivers/hid/i2c-hid/i2c-hid-core.c            | 330 +++++++++++++-----
>  include/drm/drm_panel.h                       |  89 +++++
>  12 files changed, 542 insertions(+), 95 deletions(-)
>