drm/ast: astdp: Validate display modes

Validate each display mode against the astdp transmitter chips. Filters
out modes that the chip does not support.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250204133209.403327-5-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/ast/ast_dp.c b/drivers/gpu/drm/ast/ast_dp.c
index b984a0f87f8532bdf48bf0e0f2d6b362c005fffe..00d07a905fd5c63828deeffee40d3e0a39a47478 100644 (file)
--- a/drivers/gpu/drm/ast/ast_dp.c
+++ b/drivers/gpu/drm/ast/ast_dp.c
@@ -300,6 +300,19 @@ static const struct drm_encoder_funcs ast_astdp_encoder_funcs = {
        .destroy = drm_encoder_cleanup,
 };
 
+static enum drm_mode_status
+ast_astdp_encoder_helper_mode_valid(struct drm_encoder *encoder,
+                                   const struct drm_display_mode *mode)
+{
+       int res;
+
+       res = ast_astdp_get_mode_index(mode->hdisplay, mode->vdisplay);
+       if (res < 0)
+               return MODE_NOMODE;
+
+       return MODE_OK;
+}
+
 static void ast_astdp_encoder_helper_atomic_mode_set(struct drm_encoder *encoder,
                                                     struct drm_crtc_state *crtc_state,
                                                     struct drm_connector_state *conn_state)
@@ -389,6 +402,7 @@ static int ast_astdp_encoder_helper_atomic_check(struct drm_encoder *encoder,
 }
 
 static const struct drm_encoder_helper_funcs ast_astdp_encoder_helper_funcs = {
+       .mode_valid = ast_astdp_encoder_helper_mode_valid,
        .atomic_mode_set = ast_astdp_encoder_helper_atomic_mode_set,
        .atomic_enable = ast_astdp_encoder_helper_atomic_enable,
        .atomic_disable = ast_astdp_encoder_helper_atomic_disable,