[v2,0/4] arch/parisc: Detect primary framebuffer from device

Message

Thomas Zimmermann Jan. 2, 2024, 9:52 a.m. UTC

On parisc, change detection of the primary framebuffer to test for
the Linux device instead of fbdev's fb_info in fb_is_primary_device().
Makes the test independent from fbdev.

This patchset is part of a larger effort to clean up the low-level
display handling. There are various functions that attempt to detect
the system's primary framebuffer device, such as in vgaarb, [1]
fbcon, [2] or fbmon. [3] This code should be unified in a single helper
that implements the test. The function fb_is_primary_device() already
does this, but requires fbdev on parisc. With the patchset applied, the
parisc implementation tests directly with the Linux device. No fbdev is
required.

Patch 1 adds the framebuffer's Linux device to the STI ROM structures,
which represents the graphics firmware. Patches 2 updates the stifb
driver to refer to the correct Linux device. The device is used in
patch 3 to change the test in fb_is_primary_device(). Patch 4 removes
the obsolete fb_info from the STI ROM structures.

A later patchset will update the interface of fb_is_primary_device() to
receive a Linux device instead of an instance of fb_info. This involves
several architectures, so it is better done in a separate patch.

[1] https://elixir.bootlin.com/linux/v6.6/source/drivers/pci/vgaarb.c#L557
[2] https://elixir.bootlin.com/linux/v6.6/source/drivers/video/fbdev/core/fbcon.c#L2943
[3] https://elixir.bootlin.com/linux/v6.6/source/drivers/video/fbdev/core/fbmon.c#L1503

v2:
	* fix crash during driver initialization (Helge)

Thomas Zimmermann (4):
  video/sticore: Store ROM device in STI struct
  fbdev/stifb: Allocate fb_info instance with framebuffer_alloc()
  arch/parisc: Detect primary video device from device instance
  video/sticore: Remove info field from STI struct

 arch/parisc/video/fbdev.c   |   2 +-
 drivers/video/fbdev/stifb.c | 111 ++++++++++++++++++------------------
 drivers/video/sticore.c     |   5 ++
 include/video/sticore.h     |   6 +-
 4 files changed, 66 insertions(+), 58 deletions(-)


base-commit: 25232eb8a9ac7fa0dac7e846a4bf7fba2b6db39a