The named mode could be invalid and then cmdline parser misses to validate
mode's dimensions, happily adding 0x0 mode as a valid mode. One case where
this happens is NVIDIA Tegra devices that are using downstream bootloader
which adds "video=tegrafb" to the kernel's cmdline and thus upstream Tegra
DRM driver fails to probe because of the invalid mode.
Fixes: 3aeeb13d89 ("drm/modes: Support modes names on the command line")
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190709145151.23086-1-digetx@gmail.com
The drm subsystem also uses the video= kernel parameter, and in the
documentation refers to the fbdev documentation for that parameter.
However, that documentation also says that instead of giving the mode using
its resolution we can also give a name. However, DRM doesn't handle that
case at the moment. Even though in most case it shouldn't make any
difference, it might be useful for analog modes, where different standards
might have the same resolution, but still have a few different parameters
that are not encoded in the modes (NTSC vs NTSC-J vs PAL-M for example).
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/18443e0c3bdbbd16cea4ec63bc7f2079b820b43b.1560783090.git-series.maxime.ripard@bootlin.com
struct drm_fb_helper_crtc is now just a wrapper around drm_mode_set so
use that directly instead and attach it as a modeset array onto
drm_client_dev. drm_fb_helper will use this array to store its modesets
which means it will always initialize a drm_client, but it will not
register the client (callbacks) unless it's the generic fbdev emulation.
Code will later be moved to drm_client, so add code there in a new file
drm_client_modeset.c with MIT license to match drm_fb_helper.c.
The modeset connector array size is hardcoded for the cloned case to avoid
having to pass in a value from the driver. A value of 8 is chosen to err
on the safe side. This means that the max connector argument for
drm_fb_helper_init() and drm_fb_helper_fbdev_setup() isn't used anymore,
a todo entry for this is added.
In pan_display_atomic() restore_fbdev_mode_force() is used instead of
restore_fbdev_mode_atomic() because that one will later become internal
to drm_client_modeset.
Locking order:
1. drm_fb_helper->lock
2. drm_master_internal_acquire
3. drm_client_dev->modeset_mutex
v6: Improve commit message (Sam Ravnborg)
v3:
- Use full drm_client_init/release for the modesets (Daniel Vetter)
- drm_client_for_each_modeset: use lockdep_assert_held (Daniel Vetter)
- Hook up to Documentation/gpu/drm-client.rst (Daniel Vetter)
v2:
- Add modesets array to drm_client (Daniel Vetter)
- Use a new file for the modeset code (Daniel Vetter)
- File has to be MIT licensed (Emmanuel Vadot)
- Add copyrights from drm_fb_helper.c
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190531140117.37751-3-noralf@tronnes.org
