[00/11] drm,fbdev: Move video= option to drivers/video

Message

Thomas Zimmermann Feb. 9, 2023, 1:54 p.m. UTC

The kernel's video= option sets the initial video mode. It is shared
by fbdev and DRM, but located within the fbdev code. Move it to
drivers/video/ and adapt callers. Allows DRM (and others) to use the
option without depending on fbdev.

While at it, fix the interface of the lookup functions. This requires
a number of changes. First clarify the ownership of the option string
in patch 2. The helper fb_get_options() returns the video= parameter's
value. It's sometimes a copy and sometimes the original string. Hence
callers, mostly fbdev drivers, have just leaked the returned string.
Change this to always duplicate the option string in fb_get_options()
and transfer ownership of the copy to the caller. We can then start to
fix the memory leaks in the fbdev drivers.

There's a global video= setting and a number of per-output settings.
In patches 3 to 5, support explicit lookup of the global video option
and lookup the string in fbdev's modedb and in a PS3 driver. Then
avoid exporting the global setting's internal state variable in patch 6.

Finally, in patches 7 to 11, move the video= option to drivers/video.
It can be used directly in DRM and a PS3 driver. This fixes any memory
leaks from the returned option string. For fbdev drivers, the helper
fb_get_options() remains as an adapter aroudn the new interface.

Tested with DRM and fbdev and built for the PS3.

Thomas Zimmermann (11):
  fbdev: Fix contact info in fb_cmdline.c
  fbdev: Transfer video= option strings to caller; clarify ownership
  fbdev: Support NULL for name in option-string lookup
  drivers/ps3: Read video= option with fb_get_option()
  fbdev: Read video= option with fb_get_option() in modedb
  fbdev: Unexport fb_mode_option
  fbdev: Move option-string lookup into helper
  fbdev: Handle video= parameter in video/cmdline.c
  driver/ps3: Include <video/cmdline.h> for mode parsing
  drm: Include <video/cmdline.h> for mode parsing
  drm: Fix comment on mode parsing

 drivers/gpu/drm/Kconfig               |   2 +-
 drivers/gpu/drm/drm_connector.c       |   9 +-
 drivers/gpu/drm/drm_modes.c           |   3 +-
 drivers/ps3/ps3av.c                   |   9 +-
 drivers/video/Kconfig                 |   3 +
 drivers/video/Makefile                |   1 +
 drivers/video/cmdline.c               | 133 ++++++++++++++++++++++++++
 drivers/video/fbdev/Kconfig           |   5 +-
 drivers/video/fbdev/core/Makefile     |   3 +-
 drivers/video/fbdev/core/fb_cmdline.c |  94 +++++-------------
 drivers/video/fbdev/core/modedb.c     |   8 +-
 include/linux/fb.h                    |   1 -
 include/video/cmdline.h               |  20 ++++
 13 files changed, 202 insertions(+), 89 deletions(-)
 create mode 100644 drivers/video/cmdline.c
 create mode 100644 include/video/cmdline.h


base-commit: 1a019dd7a5d25f7c1c9b77931138290e28947e6a