fbdev: omapfb: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Helge Deller <deller@gmx.de>

fbdev: omapfb/dss: Use pm_runtime_resume_and_get() instead of pm_runtime_get_sync()

Using the newest pm_runtime_resume_and_get is more appropriate
for simplifing code here.

Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

fbdev: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200707210539.GA12530@embeddedor

omapfb: fix multiple reference count leaks due to pm_runtime_get_sync

On calling pm_runtime_get_sync() the reference count of the device
is incremented. In case of failure, decrement the
reference count before returning the error.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Cc: kjlu@umn.edu
Cc: wu000273@umn.edu
Cc: Allison Randal <allison@lohutok.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Enrico Weigelt <info@metux.net>
cc: "Andrew F. Davis" <afd@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alexios Zavras <alexios.zavras@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200614030528.128064-1-pakki001@umn.edu

omapfb/dss: fix comparison to bool warning

Fix the following coccicheck warning:

drivers/video/fbdev/omap2/omapfb/dss/hdmi4.c:461:15-32: WARNING:
Comparison to bool
drivers/video/fbdev/omap2/omapfb/dss/dispc.c:891:5-35: WARNING:
Comparison of 0/1 to bool variable

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrew F. Davis <afd@ti.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200422071903.637-1-yanaijie@huawei.com

omapfb: Remove unused writeback code

Remove unused writeback code. This code will never be used, as omapfb is
being deprecated.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200313122410.7528-1-tomi.valkeinen@ti.com

omapfb/dss: remove unneeded conversions to bool

Found with scripts/coccinelle/misc/boolconv.cocci.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191016180424.23907-1-afd@ti.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234

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 version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fbdev: fix omap2/omapfb/dss/ indentation warning

Fix indentation warning (from gcc 8.1.0) in omap2/omapfb:

../drivers/video/fbdev/omap2/omapfb/dss/dispc.c: In function 'pixinc':
../drivers/video/fbdev/omap2/omapfb/dss/dispc.c:1859:2: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
else
^~~~
../drivers/video/fbdev/omap2/omapfb/dss/dispc.c:1861:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
return 0;
^~~~~~

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

omapfb: Mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

omapfb: dss: Do not duplicate features data

As features data are read only, there is no need to allocate their
copy on the heap.

Suggested-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Tested-by: Adam Ford <aford173@gmail.com> #omap3630
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Arvind Yadav <arvind.yadav.cs@gmail.com>
Cc: Markus Elfring <elfring@users.sourceforge.net>
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: Adam Ford <adam.ford@logicpd.com>
[b.zolnierkie: fixed minor CodingStyle errors reported by checkpatch.pl]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

omapfb: Create new header file for omapfb DSS implementation

Copy the content of video/omapdss.h to a new (video/omapfb_dss.h) header
file and convert the omapfb drivers to use this new file.

The new header file is needed to complete the separation of omapdrm and
omapfb implementation of DSS.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>

omapfb/dss: change CONFIG_OMAP* to CONFIG_FB_OMAP*

We need to change the config symbols of omapfb's private copy of
omapdss so that we won't have config symbol conflicts.

This patch changes the symbols from omapdss using simple replacement of
CONFIG_OMAP* to CONFIG_FB_OMAP*.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>

omapfb: copy omapdss & displays for omapfb

This patch makes a copy of the omapdss driver and the omap panel &
encoder drivers for omapfb. The purpose is to separate omapdrm and
omapfb drivers from each other.

Note that this patch only does a direct copy of the files without any
other modifications. The files are not yet used.

The original files are in:

drivers/video/fbdev/omap2/dss/
drivers/video/fbdev/omap2/displays-new/

Here's a more detailed explanation about this and the following patches,
from the introduction mail of the patch series:

A short background on the current status. We have the following
entities:

* omapdss, located in drivers/video/fbdev/omap2/dss/. This is a driver for the
display subsystem IPs used on OMAP (and related) SoCs. It offers only a
kernel internal API, and does not implement anything for fbdev or drm.

* omapdss panels and encoders, located in
drivers/video/fbdev/omap2/displays-new/. These are panel and external encoder
drivers, which use APIs offered by omapdss driver. These also don't implement
anything for fbdev or drm.

* omapdrm, located in drivers/gpu/drm/omapdrm/. This is a drm driver, which
uses omapdss and the panel/encoder drivers to operate the hardware.

* omapfb, located in drivers/video/fbdev/omap2/omapfb/. This is an fbdev
driver, which uses omapdss and the panel/encoder drivers to operate the
hardware.

* omap_vout, located in drivers/media/platform/omap/. This is a v4l2 driver,
which uses omapdss and omapfb to implement a v4l2 API for the video overlays.

So, on the top level, we have either omapdrm, or omapfb+omap_vout. Both of
those use the same low level drivers. Without going to the historical details
why the architecture is like that, I think it's finally time to change that.

The situation with omapfb+omap_vout is that it still works, but no new features
have been added for a long time, and I want to keep it working as it's still
being used. At some point in the future I'd like to remove omapfb and
omap_vout altogether.

Omapdrm, on the other hand, is being actively developed. Sharing the low level
parts with omapfb makes that development more difficult than it should be. It
also "hides" half of the development, as everything happening in the low level
parts resides under fbdev directory, not in the drm directory.

I've been wanting to clean this up for a long time, but I haven't figured out a
very good way to do it. I still haven't, but here's the best way I have come up
with.

This series makes a full copy of the low level parts, omapdss and panel/encoder
drivers. Both omapfb+omap_vout and omapdrm will have their own versions. The
copy omapfb+omap_vout get is a new copy, and the copy that omapdrm gets is just
the current files moved. This way git will associate the omapdrm version with
the old files.

The omapfb+omap_vout versions won't be touched unless there are some big issues
there.

The omapdrm versions can be refactored and cleaned up, as the omapfb support
code is no longer needed. We can perhaps also merge omapdss and omapdrm into
the same kernel module.

This series only does the copy, and the absolutely necessary parts. No further
cleanups are done yet.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>