[PATCH] drm/vkms: add support for gamma_set interface

[Sidong Yang <realwakka@gmail.com>]

Currently vkms module doesn't support gamma function for userspace. so igt
subtests in kms_plane(pixel-format-pipe-A-plan) failed for calling
drmModeCrtcSetGamma(). This patch set gamma_set interface in vkms_crtc_funcs for
support gamma function. With initializing crtc, added calls for setting gamma
size. it pass the test after this patch.

Cc: Daniel Vetter<daniel@ffwll.ch>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>

Signed-off-by: Sidong Yang <realwakka@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_crtc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
index ac85e17428f8..643435fb2ee6 100644
--- a/drivers/gpu/drm/vkms/vkms_crtc.c
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -160,6 +160,7 @@ static const struct drm_crtc_funcs vkms_crtc_funcs = {
 	.get_crc_sources	= vkms_get_crc_sources,
 	.set_crc_source		= vkms_set_crc_source,
 	.verify_crc_source	= vkms_verify_crc_source,
+	.gamma_set		= drm_atomic_helper_legacy_gamma_set,
 };
 
 static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
@@ -275,6 +276,13 @@ int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
 		return ret;
 	}
 
+	ret = drm_mode_crtc_set_gamma_size(crtc, 256);
+	if (ret) {
+		DRM_ERROR("Failed to set gamma size\n");
+		return ret;
+	}
+	drm_crtc_enable_color_mgmt(crtc, 0, false, 256);
+
 	drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
 
 	spin_lock_init(&vkms_out->lock);
-- 
2.17.1