diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2021-09-28 16:52:10 +0200 |
|---|---|---|
| committer | Thomas Zimmermann <tzimmermann@suse.de> | 2021-09-29 09:26:58 +0200 |
| commit | fd09961dbb9ca6558d8ad318a3967c1048bdb090 (patch) | |
| tree | a4a77c98b95cb318b0df91c9f32057f6822dde17 | |
| parent | 19bd6cdb9ce0522023e93b8ac065f19e59759536 (diff) | |
fbdev: simplefb: fix Kconfig dependenciesdrm-misc-fixes-2021-09-30
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
| -rw-r--r-- | drivers/of/base.c | 1 | ||||
| -rw-r--r-- | drivers/video/fbdev/Kconfig | 5 |
2 files changed, 4 insertions, 2 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index f720c0d246f2..0ac17256258d 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -36,6 +36,7 @@ LIST_HEAD(aliases_lookup); struct device_node *of_root; EXPORT_SYMBOL(of_root); struct device_node *of_chosen; +EXPORT_SYMBOL(of_chosen); struct device_node *of_aliases; struct device_node *of_stdout; static const char *of_stdout_options; diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig index d33c5cd684c0..f71668367caf 100644 --- a/drivers/video/fbdev/Kconfig +++ b/drivers/video/fbdev/Kconfig @@ -2191,8 +2191,9 @@ 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 |