drm: fix up fbdev Kconfig defaults

As a result of the recent Kconfig reworks, the default settings for the
framebuffer interfaces changed in unexpected ways:

Configurations that leave CONFIG_FB disabled but use DRM now get
DRM_FBDEV_EMULATION by default. This also turns on the deprecated /dev/fb
device nodes for machines that don't actually want it.

In turn, configurations that previously had DRM_FBDEV_EMULATION enabled
now only get the /dev/fb front-end but not the more useful framebuffer
console, which is not selected any more.

We had previously decided that any combination of the three frontends
(FB_DEVICE, FRAMEBUFFER_CONSOLE and LOGO) should be selectable, but the
new default settings mean that a lot of defconfig files would have to
get adapted.

Change the defaults back to what they were in Linux 6.5:

 - Leave DRM_FBDEV_EMULATION turned off unless CONFIG_FB
   is enabled. Previously this was a hard dependency but now the two are
   independent. However, configurations that enable CONFIG_FB probably
   also want to keep the emulation for DRM, while those without FB
   presumably did that intentionally in the past.

 - Leave FB_DEVICE turned off for FB=n. Following the same
   logic, the deprecated option should not automatically get enabled
   here, most users that had FB turned off in the past do not want it,
   even if they want the console

 - Turn the FRAMEBUFFER_CONSOLE option on if
   DRM_FBDEV_EMULATION is set to avoid having to change defconfig
   files that relied on it being selected unconditionally in the past.
   This also makes sense since both LOGO and FB_DEVICE are now disabled
   by default for builds without CONFIG_FB, but DRM_FBDEV_EMULATION
   would make no sense if all three are disabled.

Fixes: a5ae331edb02b ("drm: Drop select FRAMEBUFFER_CONSOLE for DRM_FBDEV_EMULATION")
Fixes: 701d2054fa317 ("fbdev: Make support for userspace interfaces configurable")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230911205338.2385278-1-arnd@kernel.org

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index ab9ef1c..3caa020 100644 (file)
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -136,7 +136,7 @@ config DRM_FBDEV_EMULATION
        bool "Enable legacy fbdev support for your modesetting driver"
        depends on DRM
        select FRAMEBUFFER_CONSOLE_DETECT_PRIMARY if FRAMEBUFFER_CONSOLE
-       default y
+       default FB
        help
          Choose this option if you have a need for the legacy fbdev
          support. Note that this support also provides the linux console

diff --git a/drivers/video/console/Kconfig b/drivers/video/console/Kconfig
index 1b5a319..30577b1 100644 (file)
--- a/drivers/video/console/Kconfig
+++ b/drivers/video/console/Kconfig
@@ -73,6 +73,7 @@ config DUMMY_CONSOLE_ROWS
 config FRAMEBUFFER_CONSOLE
        bool "Framebuffer Console support"
        depends on FB_CORE && !UML
+       default DRM_FBDEV_EMULATION
        select VT_HW_CONSOLE_BINDING
        select CRC32
        select FONT_SUPPORT

diff --git a/drivers/video/fbdev/core/Kconfig b/drivers/video/fbdev/core/Kconfig
index baf7e85..5ac1b06 100644 (file)
--- a/drivers/video/fbdev/core/Kconfig
+++ b/drivers/video/fbdev/core/Kconfig
@@ -28,7 +28,7 @@ config FIRMWARE_EDID
 config FB_DEVICE
        bool "Provide legacy /dev/fb* device"
        depends on FB_CORE
-       default y
+       default FB
        help
          Say Y here if you want the legacy /dev/fb* device file and
          interfaces within sysfs anc procfs. It is only required if you