[PATCH v3 0/3] 180 degrees rotation support for NVIDIA Tegra DRM

[Dmitry Osipenko <digetx@gmail.com>]

Hello!

This series adds 180° display plane rotation support to the NVIDIA Tegra
DRM driver which is needed for devices that have display panel physically
mounted upside-down, like Nexus 7 tablet device for example [1]. Since
DRM panel rotation is a new thing for a userspace, currently only
Opentegra Xorg driver [2] and a recent Weston [3] have support for the
rotated display panels, but this is more than good enough for the starter.

[1] https://patchwork.ozlabs.org/project/linux-tegra/patch/20200607154327.18589-3-digetx@gmail.com/
[2] https://github.com/grate-driver/xf86-video-opentegra/commit/28eb20a3959bbe5bc3a3b67e55977093fd5114ca
[3] https://gitlab.freedesktop.org/wayland/weston/-/merge_requests/315

Changelog:

v3: - Factored out the panel patches into standalone series [4] because
      this series doesn't have hard dependency on the panel patches and it
      should be nicer to review and apply the properly grouped patches.

    - The DRM_MODE_ROTATE_180 now isn't passed to drm_rotation_simplify(),
      like it was suggested by Ville Syrjälä in the comment to v2.

    - Added clarifying comment for the tegra_fb_is_bottom_up() in the code.

[4] https://lore.kernel.org/lkml/20200617231842.30671-1-digetx@gmail.com/T/#t

Dmitry Osipenko (3):
  drm/tegra: plane: Rename bottom_up to reflect_y
  drm/tegra: plane: Support horizontal reflection
  drm/tegra: plane: Support 180° rotation

 drivers/gpu/drm/tegra/dc.c    | 46 ++++++++++++++++++++++++++++-------
 drivers/gpu/drm/tegra/dc.h    |  3 ++-
 drivers/gpu/drm/tegra/plane.c |  3 ++-
 drivers/gpu/drm/tegra/plane.h |  3 ++-
 4 files changed, 43 insertions(+), 12 deletions(-)

-- 
2.26.0