drm/sti: remove use of drm_debugfs functions as return values

Since commit 987d65d01356 (drm: debugfs: make
drm_debugfs_create_files() never fail), drm_debugfs_create_files() never
fails, and should return void. This change therefore removes it uses as
a return value in various functions across drm/sti.

With these changes, the affected functions have been changed to use a void
return value.

v2: convert sti_mixer_debugfs_init() and sti_compositor_debugfs_init()
to return void too. Also have sti_drm_dbg_init() to return 0 to avoid
build issues.

References: https://lists.freedesktop.org/archives/dri-devel/2020-February/257183.html
Signed-off-by: Wambui Karuga <wambui.karugax@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200310133121.27913-10-wambui.karugax@gmail.com

gpu: drm: sti: Adopt SPDX identifiers

Add SPDX identifiers to files under sti directory

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Vincent Abriou <vincent.abriou@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171206112947.9569-2-benjamin.gaignard@st.com

drm/sti: fix compositor debugfs creation

Fix typo and issue while creating the vid and mixer debugfs entries.

Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

drm/sti: use vtg array instead of vtg_main/aux

This is more generic and more consistent with the other members of the
sti_compositor struct.

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Acked-by: Vincent Abriou <vincent.abriou@st.com>

drm/sti: use different notifier_block for each pipe

Each pipe shall have its own notifier block to manage the vblank event.
This fixes issues where a client registered on given pipe is later
abusively notified of events on the other pipe.

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Acked-by: Vincent Abriou <vincent.abriou@st.com>

drm: sti: use late_register and early_unregister callbacks

Make sti driver use register callback to move debugfs
initialization out of sub-components creation.
This will allow to convert driver .load() to
drm_dev_alloc() and drm_dev_register().

sti_compositor bring up 2 crtc but only one debugfs init is
needed so use drm_crtc_index to do it on the first one.
This can't be done in sti_drv because only sti_compositor have
access to the devices.
It is almost the same for sti_encoder which handle multiple
encoder while one only debugfs entry is needed so add a boolean
to avoid multiple debugfs initialization

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1466514580-15194-3-git-send-email-benjamin.gaignard@linaro.org

drm/sti: rename files and functions

replace all "sti_drm_" occurences by "sti_"

Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

drm/sti: code clean up

Purpose is to simplify the STI driver:
- remove layer structure
- consider video subdev as part of the compositor (like mixer subdev)
- remove useless STI_VID0 and STI_VID1 enum

Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

drm: sti: enable auxiliary CRTC

For stih407 SoC enable the second mixer to get two CRTC.
Allow GPD planes and encoders to be connected to this new CRTC.
Cursor plane can only be set on first CRTC.
GPD clocks needed change the parent clock depending on which
CRTC GPD are used.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

drm: sti: add Compositor

Compositor control all the input sub-device (VID, GDP)
and the mixer(s).
It is the main entry point for composition.
Layer interface is used to control the abstracted layers.

Add debug in mixer and GDP.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>