Re: [PATCH v2 0/8] Add a panel API to return panel orientation

[CK Hu <ck.hu@mediatek.com>]

Hi, Hsin-Yi:

I'm curious that panel driver setting orientation in get_modes() would
work or not. It it works, why not just set orientation in get_modes()?
I find that exynos dsi driver has implement the get_modes() [1] but
Mediatek dsi does not implement. Would you try this?

[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/exynos/exynos_drm_dsi.c?h=v5.18#n1483

Regards,
CK

On Wed, 2022-06-01 at 17:46 +0800, Hsin-Yi Wang wrote:
> Panels usually call drm_connector_set_panel_orientation(), which is
> later than drm/kms driver calling drm_dev_register(). This leads to a
> WARN()[1].
> 
> The orientation property is known earlier. For example, some panels
> parse the property through device tree during probe.
> 
> The series add a panel API drm_panel_get_orientation() for drm/kms
> drivers. The drivers can use the API to get panel's orientation, so
> they
> can call drm_connector_set_panel_orientation() before
> drm_dev_register().
> 
> Panel needs to implement .get_orientation callback to return the
> property.
> 
> [1] 
> https://urldefense.com/v3/__https://patchwork.kernel.org/project/linux-mediatek/patch/20220530081910.3947168-2-hsinyi@chromium.org/__;!!CTRNKA9wMg0ARbw!0ytf4wPxKANnYbw_fgq-eqQARnAXIHv4jwu04ZW6X6dAxZDFsJ0CltY_PvCBAQ$
>  
> 
> Hsin-Yi Wang (8):
>   drm/panel: Add an API drm_panel_get_orientation() to return panel
>     orientation
>   drm/panel: boe-tv101wum-nl6: Implement .get_orientation callback
>   drm/panel: panel-edp: Implement .get_orientation callback
>   drm/panel: lvds: Implement .get_orientation callback
>   drm/panel: panel-simple: Implement .get_orientation callback
>   drm/panel: ili9881c: Implement .get_orientation callback
>   drm/panel: elida-kd35t133: Implement .get_orientation callback
>   drm/mediatek: Config orientation property if panel provides it
> 
>  drivers/gpu/drm/drm_panel.c                    |  8 ++++++++
>  drivers/gpu/drm/mediatek/mtk_dsi.c             | 10 ++++++++++
>  drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c |  8 ++++++++
>  drivers/gpu/drm/panel/panel-edp.c              |  8 ++++++++
>  drivers/gpu/drm/panel/panel-elida-kd35t133.c   |  8 ++++++++
>  drivers/gpu/drm/panel/panel-ilitek-ili9881c.c  |  8 ++++++++
>  drivers/gpu/drm/panel/panel-lvds.c             |  8 ++++++++
>  drivers/gpu/drm/panel/panel-simple.c           |  9 +++++++++
>  include/drm/drm_panel.h                        | 10 ++++++++++
>  9 files changed, 77 insertions(+)
>