Handle the command-line parameter video= in video/cmdline.c. Implement
the fbdev helper fb_get_options() on top. Will allows to handle the
kernel parameter in DRM without fbdev dependencies.
Note that __video_get_options() has the meaning of its return value
inverted compared to fb_get_options(). The new helper returns true if
the adapter has been enabled, and false otherwise.
There is the ofonly parameter, which disables output for non-OF-based
framebuffers. It is only for offb and looks like a workaround. The actual
purpose it not clear to me. Use 'video=off' or 'nomodeset' instead.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-9-tzimmermann@suse.de
In fb_get_options(), always duplicate the returned option string and
transfer ownership of the memory to the function's caller.
Until now, only the global option string got duplicated and transferred
to the caller; the per-driver options were owned by fb_get_options().
In the end, it was impossible for the function's caller to detect if
it had to release the string's memory buffer. Hence, all calling drivers
leak the memory buffer. The leaks have existed ever since, but drivers
only call fb_get_option() once as part of module initialization. So the
amount of leaked memory is not significant.
Fix the semantics of fb_get_option() by unconditionally transferring
ownership of the memory buffer to the caller. Later patches can resolve
the memory leaks in the fbdev drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-3-tzimmermann@suse.de
Make the video_setup() function slightly easier to read by removing the
repeated checks for !global. Remove the misleading return value comment
while at it.
I'm slightly hesitant to change any of this, but here goes anyway, with
hopes that the next person to have to look at this has it a wee bit
easier.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
In drm/i915 we want to get at the video= cmdline modes even when we
don't have fbdev support enabled, so that users can always override
the kernel's initial mode selection.
But that gives us a direct depency upon the parsing code in the fbdev
subsystem. Since it's so little code just extract these 2 functions
and always build them in.
Whiel at it fix the checkpatch fail in this code.
v2: Also move fb_mode_option. Spotted by the kbuild.
v3: Review from Geert:
- Keep the old copyright notice from fb_mem.c, although I have no
idea what exactly applies.
- Only compile this when needed.
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
--
I prefer if we can merge this through drm-next since we'll use it
there in follow-up patches.
-Daniel
