I also did a full review of all callers, and only the xen driver
forgot to call drm_dev_put in the failure path. Fix that up too.

v2: I noticed that xen has a drm_driver.release hook, and uses
drm_dev_alloc(). We need to remove the kfree from
xen_drm_drv_release().

bochs also has a release hook, but leaked the drm_device ever since

commit 0a6659bd
Author: Gerd Hoffmann <kraxel@redhat.com>
Date:   Tue Dec 17 18:04:46 2013 +0100

    drm/bochs: new driver

This patch here fixes that leak.

Same for virtio, started leaking with

commit b1df3a2b


Author: Gerd Hoffmann <kraxel@redhat.com>
Date:   Tue Feb 11 14:58:04 2020 +0100

    drm/virtio: add drm_driver.release callback.

Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: xen-devel@lists.xenproject.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-5-daniel.vetter@ffwll.ch

We have lots of these. And the cleanup code tends to be of dubious
quality. The biggest wrong pattern is that developers use devm_, which
ties the release action to the underlying struct device, whereas
all the userspace visible stuff attached to a drm_device can long
outlive that one (e.g. after a hotunplug while userspace has open
files and mmap'ed buffers). Give people what they want, but with more
correctness.

Mostly copied from devres.c, with types adjusted to fit drm_device and
a few simplifications - I didn't (yet) copy over everything. Since
the types don't match code sharing looked like a hopeless endeavour.

For now it's only super simplified, no groups, you can't remove
actions (but kfree exists, we'll need that soon). Plus all specific to
drm_device ofc, including the logging. Which I didn't bother to make
compile-time optional, since none of the other drm logging is compile
time optional either.

One tricky bit here is the chicken&egg between allocating your
drm_device structure and initiliazing it with drm_dev_init. For
perfect onion unwinding we'd need to have the action to kfree the
allocation registered before drm_dev_init registers any of its own
release handlers. But drm_dev_init doesn't know where exactly the
drm_device is emebedded into the overall structure, and by the time it
returns it'll all be too late. And forcing drivers to be able clean up
everything except the one kzalloc is silly.

Work around this by having a very special final_kfree pointer. This
also avoids troubles with the list head possibly disappearing from
underneath us when we release all resources attached to the
drm_device.

v2: Do all the kerneldoc at the end, to avoid lots of fairly pointless
shuffling while getting everything into shape.

v3: Add static to add/del_dr (Neil)
Move typo fix to the right patch (Neil)

v4: Enforce contract for drmm_add_final_kfree:

Use ksize() to check that the drm_device is indeed contained somewhere
in the final kfree(). Because we need that or the entire managed
release logic blows up in a pile of use-after-frees. Motivated by a
discussion with Laurent.

v5: Review from Laurent:
- %zu instead of casting size_t
- header guards
- sorting of includes
- guarding of data assignment if we didn't allocate it for a NULL
  pointer
- delete spurious newline
- cast void* data parameter correctly in ->release call, no idea how
  this even worked before

v6: Review from Sam
- Add the kerneldoc for the managed sub-struct back in, even if it
  doesn't show up in the generated html somehow.
- Explain why __always_inline.
- Fix bisectability around the final kfree() in drm_dev_relase(). This
  is just interim code which will disappear again.
- Some whitespace polish.
- Add debug output when drmm_add_action or drmm_kmalloc fail.

v7: My bisectability fix wasn't up to par as noticed by smatch.

v8: Remove unecessary {} around if else

v9: Use kstrdup_const, which requires kfree_const and introducing a free_dr()
helper (Thomas).

v10: kfree_const goes boom on the plain "kmalloc" assignment, somehow
we need to wrap that in kstrdup_const() too!! Also renumber revision
log, I somehow reset it midway thruh.

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Neil Armstrong <narmstrong@baylibre.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324124540.3227396-1-daniel.vetter@ffwll.ch

For two reasons:

- The driver core clears this already for us after we're unloaded in
  __device_release_driver().

- It's way too late, the drm_device ->release callback might massively
  outlive the underlying physical device, since a drm_device can be
  kept alive by open drm_file or well really anything else userspace
  is still hanging onto. So if we clear this ourselves, we should
  clear it in the pci ->remove callback, not in the drm_device
  ->release callback.

Looking at git history this was fixed in the driver core with

commit 0998d063


Author: Hans de Goede <hdegoede@redhat.com>
Date:   Wed May 23 00:09:34 2012 +0200

    device-core: Ensure drvdata = NULL when no driver is bound

v2: Cite the core fix in the commit message (Chris).

v3: Fix commit message and unused variable warning (Jani).

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-3-daniel.vetter@ffwll.ch

slab does this already, and I want to use this in a memory allocation
tracker in drm for stuff that's tied to the lifetime of a drm_device,
not the underlying struct device. Kinda like devres, but for drm.

Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-2-daniel.vetter@ffwll.ch

is_color_space_conversion() is a misnomer. It checks not only if color
space conversion is needed, but also if format conversion is needed.
This is actually desired behaviour because result of this function
determines if CSC block should be enabled or not (CSC block can also do
format conversion).

In order to clear misunderstandings, let's rework
is_color_space_conversion() to do exactly what is supposed to do and add
another function which will determine if CSC block must be enabled or
not.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304232512.51616-5-jernej.skrabec@siol.net

CEA 861 standard requestis that RGB quantization range is "limited" for
CEA modes. Support that by adding CSC matrix which downscales values.

This allows proper color reproduction on TV and PC monitor at the same
time. In future, override property can be added, like "Broadcast RGB"
in i915 driver.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304232512.51616-4-jernej.skrabec@siol.net

Setting scan mode to "none" confuses some TVs like LG B8, which randomly
change overscan percentage over time. Digital outputs like HDMI and DVI,
handled by this controller, don't really need overscan, so we can always
set scan mode to underscan. Actually, this is exactly what
drm_hdmi_avi_infoframe_from_display_mode() already does, so we can just
remove offending line.

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
[updated commit message]
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304232512.51616-3-jernej.skrabec@siol.net

sun8i_mixer.h include is misplaced. Move it.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200224173901.174016-8-jernej.skrabec@siol.net

Now that de2_fmt_info contains only DRM <-> HW format mapping, it
doesn't make sense to return pointer to structure when searching by DRM
format. Rework that to return only HW format instead.

This doesn't make any functional change.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200224173901.174016-7-jernej.skrabec@siol.net

For RGB formats CSC mode is always set to none and for YUV formats
almost always set to YUV to RGB.

Add a helper function to deduce CSC mode from format.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200224173901.174016-6-jernej.skrabec@siol.net

drm_format_info structure already contains information if format is RGB
or YUV. Use that instead.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200224173901.174016-5-jernej.skrabec@siol.net

Remove unneeded #if/#endif guards for checking whether the
CONFIG_DEBUG_FS option is set or not. If the option is not set, the
compiler optimizes the functions making the guards
unnecessary.

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/20200323112802.228214-1-wambui.karugax@gmail.com

This patch adds support for afbc handling. afbc is a compressed format
which reduces the necessary memory bandwidth.

Co-developed-by: Mark Yao <mark.yao@rock-chips.com>
Signed-off-by: Mark Yao <mark.yao@rock-chips.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Reviewed-by: Sandy Huang <hjc@rock-chips.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311145541.29186-7-andrzej.p@collabora.com

track lima task start which can be combined with
dma_fence_signal to identify task execution time.

example command to record:

trace-cmd record -i \
  -e "lima:lima_task_submit" -e "lima:lima_task_run" \
  -e "*fence:*fence_signaled" -e "drm:drm_vblank_event" \
  -e "drm:drm_vblank_event_queued" sleep 4

Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200307135438.9981-1-yuq825@gmail.com

Export /sys/class/drm/cardX/device/error sysfs for user read out
error task dump file.

Tested-by: Andreas Baierl <ichgeh@imkreisrum.de>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200222024210.18697-5-yuq825@gmail.com

Save all information to start a task which can be exported to user
for debug usage. Dump file data format is specified in lima_dump.h

v2:
Add include header to address build robot complain.

Tested-by: Andreas Baierl <ichgeh@imkreisrum.de>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200307134423.24329-1-yuq825@gmail.com

Limit error tasks to save.

Tested-by: Andreas Baierl <ichgeh@imkreisrum.de>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200222024210.18697-3-yuq825@gmail.com

When task fail, we can find its process with this information.

Tested-by: Andreas Baierl <ichgeh@imkreisrum.de>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200222024210.18697-2-yuq825@gmail.com

mipi_dbi_command_stackbuf() copies the passed buffer data, so it can be
const.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200316164249.6234-1-geert+renesas@glider.be

Fix a few grammar/editorial issues spotted by Laurent Pinchart.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200314153047.2486-4-sam@ravnborg.org

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

When 'VIAFB_DEBUG' and 'VIAFB_WARN' are not defined, modify the
DEBUG_MSG() &WARN_MSG() macros to use the no_printk() macro instead of
using <empty>.
This fixes a build warning when -Wextra is used and provides
printk format checking:

../drivers/video/fbdev/via/ioctl.c:88:47: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]

Also use %lu to print an unsigned long instead of just %l, to fix
a printk format warning:

../drivers/video/fbdev/via/viafbdev.c: In function ‘viafb_dvp0_proc_write’:
../drivers/video/fbdev/via/viafbdev.c:1148:14: warning: unknown conversion type character ‘]’ in format [-Wformat=]
    DEBUG_MSG("DVP0:reg_val[%l]=:%x\n", i,

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200315041002.24473-7-rdunlap@infradead.org

When 'DEBUG' is not defined, modify the DPRINTK() macro to use the
no_printk() macro instead of using <empty>.
This fixes build warnings when -Wextra is used and provides
printk format checking:

../drivers/video/fbdev/pm2fb.c:227:38: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../drivers/video/fbdev/pm3fb.c:1039:33: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]

Also drop one argument in two DPRINTK() macro uses to provide the
correct number of arguments and use the correct field in one case
to fix a build error:

../drivers/video/fbdev/pm3fb.c:353:9: error: ‘struct fb_info’ has no member named ‘current_par’
     info->current_par->depth);

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200315041002.24473-6-rdunlap@infradead.org

When 'SAVAGEFB_DEBUG' is not defined, modify the DBG() macro to use the
no_printk() macro instead of using <empty>.
This fixes a build warning when -Wextra is used and provides
printk format checking:

../drivers/video/fbdev/savage/savagefb_driver.c:2411:13: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200315041002.24473-5-rdunlap@infradead.org

When 'DEBUG' is not defined, modify the dprintk() macro to use the
no_printk() macro instead of using <empty>.
This fixes build warnings when -Wextra is used and provides
printk format checking:

../drivers/video/fbdev/matrox/matroxfb_base.c:635:77: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../drivers/video/fbdev/matrox/matroxfb_Ti3026.c:632:54: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
../drivers/video/fbdev/matrox/matroxfb_Ti3026.c:654:53: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200315041002.24473-4-rdunlap@infradead.org

When 'DEBUG' is not defined, modify the DPRINTK() macro to use the
no_printk() macro instead of using <empty>.
This fixes a build warning when -Wextra is used and provides
printk format checking:

../drivers/video/fbdev/aty/atyfb_base.c:784:61: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200315041002.24473-3-rdunlap@infradead.org

When 'DEBUG' is not defined, modify the DPRINTK() macro to use the
no_printk() macro instead of using <empty>.
This fixes a build warning when -Wextra is used and provides
printk format checking:

../drivers/video/fbdev/core/fbmon.c:812:47: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../drivers/video/fbdev/core/fbmon.c:842:24: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
../drivers/video/fbdev/core/fbmon.c:847:24: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200315041002.24473-2-rdunlap@infradead.org

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311093230.24900-4-tiwai@suse.de

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311093230.24900-3-tiwai@suse.de

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311093230.24900-2-tiwai@suse.de

After commit f651c8b0

 ("drm/virtio: factor out the sg_table from
virtio_gpu_object"), virtio_gpu_create_object allocates too small space
to fit everything in. It is because it allocates struct
virtio_gpu_object, but should allocate a newly added struct
virtio_gpu_object_shmem which has 2 more members.

So fix that by using correct type in virtio_gpu_create_object.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: http://patchwork.freedesktop.org/patch/msgid/20200319100421.16267-1-jslaby@suse.cz
Fixes: f651c8b0

 ("drm/virtio: factor out the sg_table from virtio_gpu_object")
Cc: Gurchetan Singh <gurchetansingh@chromium.org>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

drm_mode_config_init() may not have been called when the driver/device
doesn't support modeset. That will cause drm_mode_config_validate()
to oops. Skip the validation for !modeset.

TODO: We may want to consider calling drm_mode_config_init()
unconditionally to avoid similar issues elsewhere...

Fixes: 74d2aacb

 ("drm: Validate encoder->possible_clones")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200318182518.31618-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

We're getting some random other stuff that we're not really interested
in, so match only word boundaries. Also avoid the capture group while
at it.

Suggested by Joe Perches.

Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: Joe Perches <joe@perches.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200317205643.1028398-1-daniel.vetter@ffwll.ch

As a result of commit 987d65d0

 (drm: debugfs: make
drm_debugfs_create_files() never fail) and changes to various debugfs
functions in drm/core and across various drivers, there is no need for
the drm_driver.debugfs_init() hook to have a return value. Therefore,
declare it as void.

This also includes refactoring all users of the .debugfs_init() hook to
return void across the subsystem.

v2: include changes to the hook and drivers that use it in one patch to
prevent driver breakage and enable individual successful compilation of
this change.

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/20200310133121.27913-18-wambui.karugax@gmail.com

WARN if the encoder possible_crtcs is effectively empty or contains
bits for non-existing crtcs.

v2: Move to drm_mode_config_validate() (Daniel)
    Make the docs say we WARN when this is wrong (Daniel)
    Extract full_crtc_mask()

Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-7-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Many drivers are populating encoder->possible_clones wrong. Let's
persuade them to get it right by adding some loud WARNs.

We'll cross check the bits between any two encoders. So either
both encoders can clone with the other, or neither can.

We'll also complain about effectively empty possible_clones, and
possible_clones containing bits for encoders that don't exist.

v2: encoder->possible_clones now includes the encoder itelf
v3: Move to drm_mode_config_validate() (Daniel)
    Document that you get a WARN when this is wrong (Daniel)
    Extract full_encoder_mask()
v4: !! instead of ! (Daniel)

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-6-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

It's not at all clear what cloning options this driver supports.
So let's just clear possible_clones instead of setting it to some
bogus value.

v2: Adjust the FIXME (Daniel)

Cc: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-5-ville.syrjala@linux.intel.com

I doubt the DP+DP and SDVO+SDVO cloning works for this driver.
i915 at least doesn't do those. Truthfully there could be some very
specific circumstances where some of them would do doable, but
genereally it's too much pain to deal with so we've chose not to
bother. Let's use the same approach for gma500.

Also the LVDS+LVDS and DSI+DSI cases probably don't really exist as
there is one of each at most.

This does mean we'll now leave possible_clones at 0 for these encoder
types whereas previosuly we included the encoder itself in the bitmask.
But that's fine as the core now treaks 0 as a special case and adds
the encoder itself into the final bitmask reported to userspace.

Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-3-ville.syrjala@linux.intel.com

The docs say possible_clones should always include the encoder itself.
Since most drivers don't want to deal with the complexities of cloning
let's allow them to set possible_clones=0 and instead we'll fix that
up in the core.

We can't put this special case into drm_encoder_init() because drivers
will have to fill up possible_clones after adding all the relevant
encoders. Otherwise they wouldn't know the proper encoder indexes to
use. So we'll just do it just before registering the device.

v2: Don't set the bit if possible_clones!=0 so that the
    validation (coming soon) will WARN (Thomas)
    Fix up the docs to allow possible_clones==0 (Daniel)
    .late_register() is too late, introduce drm_mode_config_validate()
    which gets called _before_ we register the char device (Daniel)

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-2-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Since 987d65d0

 (drm: debugfs: make drm_debugfs_create_files() never
fail), there is no need to check the return value of
drm_debugfs_create_files(). Therefore, remove remove unnecessary checks
and error handling statement blocks for its return value.

These changes also enable changing drm_debugfs_create_files() to return
void.

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/20200310133121.27913-17-wambui.karugax@gmail.com