[PATCH] drm/vkms: Unset preferred_depth

[Daniel Vetter]

There's a confusion between the preferred_depth uapi and the generic
fbdev helpers. Former wants depth, latter wants bpp, and for XRGB8888
they don't match. Which hit me with vkms, which wants that.

All other drivers setting this and using the generic fbdev helpers use
16, where both numbers match, for RGB565.

Since fixing this is a bit involved (I think for atomic drivers we
should just compute this all internally from the format list of the
first primary plane) paper over the issue in vkms by using defaults
everywhere. Then userspace will pick XRGB8888, and fbdev helpers will
do the same, and we have what we want.

Reported-by: Simon Ser <contact at emersion.fr>
Cc: Simon Ser <contact at emersion.fr>
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo at gmail.com>
Cc: Melissa Wen <melissa.srw at gmail.com>
Cc: Haneen Mohammed <hamohammed.sa at gmail.com>
Cc: Daniel Vetter <daniel at ffwll.ch>
---
 drivers/gpu/drm/vkms/vkms_drv.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index 25faba5aac08..98ba844ae77d 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -114,7 +114,10 @@ static int vkms_modeset_init(struct vkms_device *vkmsdev)
 	dev->mode_config.max_height = YRES_MAX;
 	dev->mode_config.cursor_width = 512;
 	dev->mode_config.cursor_height = 512;
-	dev->mode_config.preferred_depth = 32;
+	/* FIXME: There's a confusion between bpp and depth between this and
+	 * fbdev helpers. We have to go with 0, meaning "pick the default",
+	 * which ix XRGB8888 in all cases. */
+	dev->mode_config.preferred_depth = 0;
 	dev->mode_config.helper_private = &vkms_mode_config_helpers;
 
 	return vkms_output_init(vkmsdev, 0);
-- 
2.28.0