egl: implement eglQueryDmaBufFormatsEXT

allow egl clients to query the dmabuf formats supported on this platform.

v2: return EGLBoolean.
v3: Check DRIimageExtension version before querying (Daniel Stone).
v4: move to DRIimageExtension version 15, error checking (Jason Ekstrand).

Signed-off-by: Louis-Francis Ratté-Boulianne <lfrb@collabora.com>
Signed-off-by: Varad Gautam <varad.gautam@collabora.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

src/egl/drivers/dri2/egl_dri2.c

@@ -2157,6 +2157,27 @@ dri2_check_dma_buf_format(const _EGLImageAttribs *attrs)
    return plane_n;
 }
 
+static EGLBoolean
+dri2_query_dma_buf_formats(_EGLDriver *drv, _EGLDisplay *disp,
+                            EGLint max, EGLint *formats, EGLint *count)
+{
+   struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+   if (max < 0 || (max > 0 && formats == NULL)) {
+      _eglError(EGL_BAD_PARAMETER, "invalid value for max count of formats");
+      return EGL_FALSE;
+   }
+
+   if (dri2_dpy->image->base.version < 15 ||
+       dri2_dpy->image->queryDmaBufFormats == NULL)
+      return EGL_FALSE;
+
+   if (!dri2_dpy->image->queryDmaBufFormats(dri2_dpy->dri_screen, max,
+                                            formats, count))
+      return EGL_FALSE;
+
+   return EGL_TRUE;
+}
+
 /**
  * The spec says:
  *
@@ -3094,6 +3115,7 @@ _eglBuiltInDriverDRI2(const char *args)
    dri2_drv->base.API.ExportDRMImageMESA = dri2_export_drm_image_mesa;
    dri2_drv->base.API.ExportDMABUFImageQueryMESA = dri2_export_dma_buf_image_query_mesa;
    dri2_drv->base.API.ExportDMABUFImageMESA = dri2_export_dma_buf_image_mesa;
+   dri2_drv->base.API.QueryDmaBufFormatsEXT = dri2_query_dma_buf_formats;
 #endif
 #ifdef HAVE_WAYLAND_PLATFORM
    dri2_drv->base.API.BindWaylandDisplayWL = dri2_bind_wayland_display_wl;

src/egl/main/eglapi.c

@@ -2386,6 +2386,24 @@ _eglFunctionCompare(const void *key, const void *elem)
    return strcmp(procname, entrypoint->name);
 }
 
+static EGLBoolean EGLAPIENTRY
+eglQueryDmaBufFormatsEXT(EGLDisplay dpy, EGLint max_formats,
+                         EGLint *formats, EGLint *num_formats)
+{
+   _EGLDisplay *disp = _eglLockDisplay(dpy);
+   _EGLDriver *drv;
+   EGLBoolean ret;
+
+   _EGL_FUNC_START(NULL, EGL_NONE, NULL, EGL_FALSE);
+
+   _EGL_CHECK_DISPLAY(disp, EGL_FALSE, drv);
+
+   ret = drv->API.QueryDmaBufFormatsEXT(drv, disp, max_formats, formats,
+                                        num_formats);
+
+   RETURN_EGL_EVAL(disp, ret);
+}
+
 __eglMustCastToProperFunctionPointerType EGLAPIENTRY
 eglGetProcAddress(const char *procname)
 {

src/egl/main/eglapi.h

@@ -198,6 +198,10 @@ struct _egl_api
    int (*GLInteropExportObject)(_EGLDisplay *dpy, _EGLContext *ctx,
                                 struct mesa_glinterop_export_in *in,
                                 struct mesa_glinterop_export_out *out);
+
+   EGLBoolean (*QueryDmaBufFormatsEXT)(_EGLDriver *drv, _EGLDisplay *dpy,
+                                       EGLint max_formats, EGLint *formats,
+                                       EGLint *num_formats);
 };
 
 #ifdef __cplusplus

src/egl/main/eglentrypoint.h

@@ -56,6 +56,7 @@ EGL_ENTRYPOINT(eglPostSubBufferNV)
 EGL_ENTRYPOINT(eglQueryAPI)
 EGL_ENTRYPOINT(eglQueryContext)
 EGL_ENTRYPOINT(eglQueryDebugKHR)
+EGL_ENTRYPOINT(eglQueryDmaBufFormatsEXT)
 EGL_ENTRYPOINT(eglQueryString)
 EGL_ENTRYPOINT(eglQuerySurface)
 EGL_ENTRYPOINT(eglQueryWaylandBufferWL)