tree a2b5555fe2ff49419670e8c03cc7fac6763706d7
parent f6382f186d29827501353af47c3c4134bab5f0d3
author Jyri Sarha <jsarha@ti.com> 1460031023 +0300
committer Jyri Sarha <jsarha@ti.com> 1470686704 +0300

drm/tilcdc: Add tilcdc_crtc_atomic_check()

Add tilcdc_crtc_atomic_check(). Checks the display mode validity and
the presence of the mandatory primary plane.

The drm_crtc_helper_funcs mode_fixup() callback is left untouched and
the check function does no try to do its job on purpose, despite what
the mode_fixup() callback's documentations suggests.

The plane's check() callback needs to set drm_crtc_state's
->mode_changed to true if the pixel format for the framebuffer
changes. Because of this drm_mode_config_funcs atomic_check() callback
needs to call drm_atomic_helper_check_modeset() once more after it has
called drm_atomic_helper_check_planes(). If the fixing of the
adjusted_mode would be done in drm_crtc_helper_funcs atomic_check()
callback, it would get over written by the extra
drm_atomic_helper_check_modeset() call.

Signed-off-by: Jyri Sarha <jsarha@ti.com>