[Buildroot] [PATCH] package/qt6/qt6base: don't require gbm for eglfs

[Fred Lefranc]

From: Fred Lefranc <fred.lefranc+evs at gmail.com>

Hi all,

While trying to enable Qt 6 with the eglfs eglfs_viv backend on a
32-bit i.MX6 target (imx-gpu-viv, framebuffer output), I hit the
package dependency-chain consistency error, because qt6base pulls in
libgbm/libdrm unconditionally for eglfs even though the Vivante
framebuffer EGL integration needs neither.

The root cause is that qt6base treats GBM as a hard requirement for
*all* of eglfs, whereas GBM/KMS is only needed by the eglfs_kms
backend. This patch decouples the two: eglfs now only requires libegl,
and GBM/KMS support is enabled conditionally when a gbm provider is
available.

Tested:
 - i.MX6Q (Cortex-A9, glibc, EABIhf), imx-gpu-viv FB output: qt6base
   builds, libqeglfs-viv-integration.so is produced, and a Qt app runs
   with -platform eglfs / QT_QPA_EGLFS_INTEGRATION=eglfs_viv.

I wasn't sure whether maintainers prefer keeping a Config.in comment
to explain that eglfs without gbm only provides vendor/fb backends -
happy to add one. Feedback welcome.

Thanks,
Fred

Fred Lefranc (1):
  package/qt6/qt6base: don't require gbm for eglfs

 package/qt6/qt6base/Config.in  |  2 +-
 package/qt6/qt6base/qt6base.mk | 12 ++++++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

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2.34.1