drm core/helpers and MIT license

[Daniel Vetter]

Hi all,

Dave and me chatted about this last week on irc. Essentially we have:

$ git grep SPDX.*GPL -- ':(glob)drivers/gpu/drm/*c'
drivers/gpu/drm/drm_client.c:// SPDX-License-Identifier: GPL-2.0
drivers/gpu/drm/drm_damage_helper.c:// SPDX-License-Identifier: GPL-2.0 OR MIT
drivers/gpu/drm/drm_dp_cec.c:// SPDX-License-Identifier: GPL-2.0
drivers/gpu/drm/drm_edid_load.c:// SPDX-License-Identifier: GPL-2.0-or-later
drivers/gpu/drm/drm_fb_cma_helper.c:// SPDX-License-Identifier: GPL-2.0-or-later
drivers/gpu/drm/drm_format_helper.c:/* SPDX-License-Identifier: GPL-2.0 */
drivers/gpu/drm/drm_gem_cma_helper.c:// SPDX-License-Identifier:
GPL-2.0-or-later
drivers/gpu/drm/drm_gem_framebuffer_helper.c://
SPDX-License-Identifier: GPL-2.0-or-later
drivers/gpu/drm/drm_gem_shmem_helper.c:// SPDX-License-Identifier: GPL-2.0
drivers/gpu/drm/drm_gem_ttm_helper.c:// SPDX-License-Identifier:
GPL-2.0-or-later
drivers/gpu/drm/drm_gem_vram_helper.c:// SPDX-License-Identifier:
GPL-2.0-or-later
drivers/gpu/drm/drm_hdcp.c:// SPDX-License-Identifier: GPL-2.0
drivers/gpu/drm/drm_lease.c:// SPDX-License-Identifier: GPL-2.0-or-later
drivers/gpu/drm/drm_mipi_dbi.c:// SPDX-License-Identifier: GPL-2.0-or-later
drivers/gpu/drm/drm_of.c:// SPDX-License-Identifier: GPL-2.0-only
drivers/gpu/drm/drm_simple_kms_helper.c:// SPDX-License-Identifier:
GPL-2.0-or-later
drivers/gpu/drm/drm_sysfs.c:// SPDX-License-Identifier: GPL-2.0-only
drivers/gpu/drm/drm_vma_manager.c:// SPDX-License-Identifier: GPL-2.0 OR MIT
drivers/gpu/drm/drm_vram_helper_common.c:// SPDX-License-Identifier:
GPL-2.0-or-later
drivers/gpu/drm/drm_writeback.c:// SPDX-License-Identifier: GPL-2.0

One is GPL+MIT, so ok, and one is a default GPL-only header from
Greg's infamous patch (so could probably be changed to MIT license
header). I only looked at .c sources, since headers are worse wrt
having questionable default headers. So about 18 files with clear GPL
licenses thus far in drm core/helpers.

Looking at where that code came from, it is mostly from GPL-only
drivers (we have a lot of those nowadays), so seems legit non-MIT
licensed. Question is now what do we do:

- Nothing, which means GPL will slowly encroach on drm core/helpers,
which is roughly the same as ...

- Throw in the towel on MIT drm core officially. Same as above, except
lets just make it official.

- Try to counter this, which means at least a) relicensing a bunch of
stuff b) rewriting a bunch of stuff c) making sure that's ok with
everyone, there's a lot of GPL-by-default for the kernel (that's how
we got most of the above code through merged drivers I think). I
suspect that whomever cares will need to put in the work to make this
happen (since it will need a pile of active resistance at least).

Cc maintainers/driver teams who might care most about this.

Also if people could cc *bsd, they probably care and I don't know best
contacts for graphics stuff (or anything else really at all).

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch