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| author | Arnd Bergmann <arnd@arndb.de> | 2021-09-28 16:52:10 +0200 |
|---|---|---|
| committer | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2021-10-06 11:12:28 +0200 |
| commit | ec7cc3f74b4236860ce612656aa5be7936d1c594 (patch) | |
| tree | 55ec5f11e628f70d2309c25534816d3b61b3c5f7 /drivers/video | |
| parent | 413e8d06ad896dae9bbc6f97b0abea5eae5495f1 (diff) | |
| download | linux-ec7cc3f74b4236860ce612656aa5be7936d1c594.tar.gz linux-ec7cc3f74b4236860ce612656aa5be7936d1c594.tar.bz2 linux-ec7cc3f74b4236860ce612656aa5be7936d1c594.zip | |
fbdev: simplefb: fix Kconfig dependencies
Configurations with both CONFIG_FB_SIMPLE=y and CONFIG_DRM_SIMPLEDRM=m
are allowed by Kconfig because the 'depends on !DRM_SIMPLEDRM' dependency
does not disallow FB_SIMPLE as long as SIMPLEDRM is not built-in. This
can however result in a build failure when cfb_fillrect() etc are then
also in loadable modules:
x86_64-linux-ld: drivers/video/fbdev/simplefb.o:(.rodata+0x1f8): undefined reference to `cfb_fillrect'
x86_64-linux-ld: drivers/video/fbdev/simplefb.o:(.rodata+0x200): undefined reference to `cfb_copyarea'
x86_64-linux-ld: drivers/video/fbdev/simplefb.o:(.rodata+0x208): undefined reference to `cfb_imageblit'
To work around this, change FB_SIMPLE to be a 'tristate' symbol,
which still allows both to be =m together, but not one of them to
be =y if the other one is =m. If a distro kernel picks this
configuration, it can be determined by local policy which of
the two modules gets loaded. The 'of_chosen' export is needed
as this is the first loadable module referencing it.
Alternatively, the Kconfig dependency could be changed to
'depends on DRM_SIMPLEDRM=n', which would forbid the configuration
with both drivers.
Fixes: 11e8f5fd223b ("drm: Add simpledrm driver")
Acked-by: Rob Herring <robh@kernel.org> # for drivers/of/
Link: https://lore.kernel.org/all/20210721151839.2484245-1-arnd@kernel.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch> # fbdev support
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Borislav Petkov <bp@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # v5.14+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210928145243.1098064-1-arnd@kernel.org
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Diffstat (limited to 'drivers/video')
| -rw-r--r-- | drivers/video/fbdev/Kconfig | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig index b26b79dfcac9..6ed5e608dd04 100644 --- a/drivers/video/fbdev/Kconfig +++ b/drivers/video/fbdev/Kconfig @@ -2193,8 +2193,9 @@ config FB_HYPERV This framebuffer driver supports Microsoft Hyper-V Synthetic Video. config FB_SIMPLE - bool "Simple framebuffer support" - depends on (FB = y) && !DRM_SIMPLEDRM + tristate "Simple framebuffer support" + depends on FB + depends on !DRM_SIMPLEDRM select FB_CFB_FILLRECT select FB_CFB_COPYAREA select FB_CFB_IMAGEBLIT |