drm/exynos: Implement fbdev emulation as in-kernel client

Move code from ad-hoc fbdev callbacks into DRM client functions
and remove the old callbacks. The functions instruct the client
to poll for changed output or restore the display. The DRM core
calls both, the old callbacks and the new client helpers, from
the same places. The new functions perform the same operation as
before, so there's no change in functionality.

Replace all code that initializes or releases fbdev emulation
throughout the driver. Instead initialize the fbdev client by a
single call to exynos_fbdev_setup() after exynos has registered its
DRM device. As in most drivers, exynos' fbdev emulation now acts
like a regular DRM client.

The fbdev client setup consists of the initial preparation and the
hot-plugging of the display. The latter creates the fbdev device
and sets up the fbdev framebuffer. The setup performs display
hot-plugging once. If no display can be detected, DRM probe helpers
re-run the detection on each hotplug event.

A call to drm_dev_unregister() releases the client automatically.
No further action is required within exynos. If the fbdev framebuffer
has been fully set up, struct fb_ops.fb_destroy implements the
release. For partially initialized emulation, the fbdev client
reverts the initial setup.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gpu/drm/exynos: Convert drm_atomic_helper_suspend/resume()

convert drm_atomic_helper_suspend/resume() to use
drm_mode_config_helper_suspend/resume().

exynos_drm_fbdev_suspend/resume can be removed
as drm_mode_config_helper_suspend/resume has
implement the same in generic way.

Remove suspend_state from exynos_drm_private
struct as it is no more useful.

Signed-off-by: Ajit Negi <ajitn.linux@gmail.com>
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm/exynos: Use drm_fb_helper_lastclose() and _poll_changed()

This driver can use drm_fb_helper_lastclose() as its .lastclose callback.
It can also use drm_fb_helper_output_poll_changed() as its
.output_poll_changed callback.

Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Inki Dae <inki.dae@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171205182504.41923-5-noralf@tronnes.org

drm/exynos: Fix suspend/resume support

Commit 7d902c05b480 ("drm: Nuke drm_atomic_helper_connector_dpms")
removed drm_atomic_helper_connector_dpms() helper saying that it was a dead
code. It was however indirectly used by Exynos DRM driver for implementing
suspend/resume support. To fix this regression (after that patch Exynos DRM
suspend/resume functions became no-ops and hardware fails to suspend),
this patch rewrites them with drm_atomic_helper_suspend/resume() helpers.

Fixes: 7d902c05b480 ("drm: Nuke drm_atomic_helper_connector_dpms")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm/exynos: build fbdev code conditionally

Fbdev code should be compiled only if CONFIG_DRM_FBDEV_EMULATION option
is enabled. The patch fixes exynos-drm code trying to manipulate
fbdev data which is not initialized in case CONFIG_DRM_FBDEV_EMULATION
is disabled.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm/exynos: build fbdev code conditionally

Fbdev code should be compiled only if CONFIG_DRM_FBDEV_EMULATION option
is enabled. The patch fixes exynos-drm code trying to manipulate
fbdev data which is not initialized in case CONFIG_DRM_FBDEV_EMULATION
is disabled.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm/exynos: change file license to GPL

This patch changes file license to GPL

Most of exynos files had been copied from some random
file and not updated correctly. So this patch corrects
the file license.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

DRM: add DRM Driver for Samsung SoC EXYNOS4210.

This patch is a DRM Driver for Samsung SoC Exynos4210 and now enables
only FIMD yet but we will add HDMI support also in the future.

this patch is based on git repository below:
git://people.freedesktop.org/~airlied/linux.git
branch name: drm-next
commit-id: 88ef4e3f4f616462b78a7838eb3ffc3818d30f67

you can refer to our working repository below:
http://git.infradead.org/users/kmpark/linux-2.6-samsung
branch name: samsung-drm

We tried to re-use lowlevel codes of the FIMD driver(s3c-fb.c
based on Linux framebuffer) but couldn't so because lowlevel codes
of s3c-fb.c are included internally and so FIMD module of this driver has
its own lowlevel codes.

We used GEM framework for buffer management and DMA APIs(dma_alloc_*)
for buffer allocation so we can allocate physically continuous memory
for DMA through it and also we could use CMA later if CMA is applied to
mainline.

Refer to this link for CMA(Continuous Memory Allocator):
http://lkml.org/lkml/2011/7/20/45

this driver supports only physically continuous memory(non-iommu).

Links to previous versions of the patchset:
v1: < https://lwn.net/Articles/454380/ >
v2: < http://www.spinics.net/lists/kernel/msg1224275.html >
v3: < http://www.spinics.net/lists/dri-devel/msg13755.html >
v4: < http://permalink.gmane.org/gmane.comp.video.dri.devel/60439 >
v5: < http://comments.gmane.org/gmane.comp.video.dri.devel/60802 >

Changelog v2:
DRM: add DRM_IOCTL_SAMSUNG_GEM_MMAP ioctl command.

this feature maps user address space to physical memory region
once user application requests DRM_IOCTL_SAMSUNG_GEM_MMAP ioctl.

DRM: code clean and add exception codes.

Changelog v3:
DRM: Support multiple irq.

FIMD and HDMI have their own irq handler but DRM Framework can regiter
only one irq handler this patch supports mutiple irq for Samsung SoC.

DRM: Consider modularization.

each DRM, FIMD could be built as a module.

DRM: Have indenpendent crtc object.

crtc isn't specific to SoC Platform so this patch gets a crtc
to be used as common object.
created crtc could be attached to any encoder object.

DRM: code clean and add exception codes.

Changelog v4:
DRM: remove is_defult from samsung_fb.

is_default isn't used for default framebuffer.

DRM: code refactoring to fimd module.
this patch is be considered with multiple display objects and
would use its own request_irq() to register a irq handler instead of
drm framework's one.

DRM: remove find_samsung_drm_gem_object()

DRM: move kernel private data structures and definitions to driver folder.

samsung_drm.h would contain only public information for userspace
ioctl interface.

DRM: code refactoring to gem modules.
buffer module isn't dependent of gem module anymore.

DRM: fixed security issue.

DRM: remove encoder porinter from specific connector.

samsung connector doesn't need to have generic encoder.

DRM: code clean and add exception codes.

Changelog v5:
DRM: updated fimd(display controller) driver.
added various pixel formats, color key and pixel blending features.

DRM: removed end_buf_off from samsung_drm_overlay structure.
this variable isn't used and end buffer address would be
calculated by each sub driver.

DRM: use generic function for mmap_offset.
replaced samsung_drm_gem_create_mmap_offset() and
samsung_drm_free_mmap_offset() with generic ones applied
to mainline recentrly.

DRM: removed unnecessary codes and added exception codes.

DRM: added comments and code clean.

Changelog v6:
DRM: added default config options.

DRM: added padding for 64-bit align.

DRM: changed prefix 'samsung' to 'exynos'

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>