kmsdrm: Init cursor surface on SetCursor() ONLY. Removal of dynamic modeset because it causes A LOT of problems with some kernel video drivers. Some refactoring and cleanups.

src/video/kmsdrm/SDL_kmsdrmopengles.c

@@ -111,11 +111,11 @@ KMSDRM_GLES_SwapWindow(_THIS, SDL_Window * window)
        be chosen by EGL as back buffer to draw on), and get a handle to it to request the pageflip on it. */
     windata->next_bo = KMSDRM_gbm_surface_lock_front_buffer(windata->gs);
     if (!windata->next_bo) {
-	return SDL_SetError("Failed to lock frontbuffer");
+	return SDL_SetError("Failed to lock frontbuffer on GBM surface destruction");
     }
     fb = KMSDRM_FBFromBO(_this, windata->next_bo);
     if (!fb) {
-	 return SDL_SetError("Failed to get a new framebuffer");
+	 return SDL_SetError("Failed to get a new framebuffer on GBM surface destruction");
     }
 
     /* Add the pageflip to te request list. */
@@ -125,9 +125,8 @@ KMSDRM_GLES_SwapWindow(_THIS, SDL_Window * window)
        We need e a non-blocking atomic commit for triple buffering, because we 
        must not block on this atomic commit so we can re-enter program loop once more. */
     ret = drm_atomic_commit(_this, SDL_FALSE);
-
     if (ret) {
-        return SDL_SetError("failed to issue atomic commit");
+        return SDL_SetError("failed to issue atomic commit on GBM surface destruction");
     }
 
     /* Release the last front buffer so EGL can chose it as back buffer and render on it again. */

src/video/kmsdrm/SDL_kmsdrmsym.h

@@ -61,21 +61,8 @@ SDL_KMSDRM_SYM(int,drmModeAddFB2WithModifiers,(int fd, uint32_t width, uint32_t
 SDL_KMSDRM_SYM(int,drmModeRmFB,(int fd, uint32_t bufferId))
 SDL_KMSDRM_SYM(drmModeFBPtr,drmModeGetFB,(int fd, uint32_t buf))
 SDL_KMSDRM_SYM(drmModeCrtcPtr,drmModeGetCrtc,(int fd, uint32_t crtcId))
-SDL_KMSDRM_SYM(int,drmModeSetCrtc,(int fd, uint32_t crtcId, uint32_t bufferId,
-                                   uint32_t x, uint32_t y, uint32_t *connectors, int count,
-                                   drmModeModeInfoPtr mode))
-SDL_KMSDRM_SYM(int,drmModeSetCursor,(int fd, uint32_t crtcId, uint32_t bo_handle,
-                                     uint32_t width, uint32_t height))
-SDL_KMSDRM_SYM(int,drmModeSetCursor2,(int fd, uint32_t crtcId, uint32_t bo_handle,
-                                      uint32_t width, uint32_t height,
-                                      int32_t hot_x, int32_t hot_y))
-SDL_KMSDRM_SYM(int,drmModeMoveCursor,(int fd, uint32_t crtcId, int x, int y))
 SDL_KMSDRM_SYM(drmModeEncoderPtr,drmModeGetEncoder,(int fd, uint32_t encoder_id))
 SDL_KMSDRM_SYM(drmModeConnectorPtr,drmModeGetConnector,(int fd, uint32_t connector_id))
-SDL_KMSDRM_SYM(int,drmHandleEvent,(int fd,drmEventContextPtr evctx))
-SDL_KMSDRM_SYM(int,drmModePageFlip,(int fd, uint32_t crtc_id, uint32_t fb_id,
-                                    uint32_t flags, void *user_data))
-
 
 /* Atomic functions */
 

src/video/kmsdrm/SDL_kmsdrmvideo.h

@@ -53,11 +53,6 @@ typedef struct SDL_VideoData
     int num_windows;
 } SDL_VideoData;
 
-typedef struct SDL_DisplayModeData
-{
-    int mode_index;
-} SDL_DisplayModeData;
-
 struct plane {
 	drmModePlane *plane;
 	drmModeObjectProperties *props;
@@ -105,12 +100,15 @@ typedef struct SDL_DisplayData
 typedef struct SDL_WindowData
 {
     SDL_VideoData *viddata;
+    /* SDL internals expect EGL surface to be here, and in KMSDRM the GBM surface is
+       what supports the EGL surface on the driver side, so all these surfaces and buffers
+       are expected to be here, in the struct pointed by SDL_Window driverdata pointer: this one.
+       So don't try to move these to dispdata!  */
     struct gbm_surface *gs;
     struct gbm_bo *bo;
     struct gbm_bo *next_bo;
-    struct gbm_bo *crtc_bo;
+
 #if SDL_VIDEO_OPENGL_EGL
-    SDL_bool egl_surface_dirty;
     EGLSurface egl_surface;
 #endif
 } SDL_WindowData;