drm: Add primary plane helpers (v3)

When we expose non-overlay planes to userspace, they will become
accessible via standard userspace plane API's.  We should be able to
handle the standard plane operations against primary planes in a generic
way via the modeset handler.

Drivers that can program primary planes more efficiently, that want to
use their own primary plane structure to track additional information,
or that don't have the limitations assumed by the helpers are free to
provide their own implementation of some or all of these handlers.

v3: Tweak kerneldoc formatting slightly to avoid ugliness
v2:
 - Move plane helpers to a new file (drm_plane_helper.c)
 - Tighten checks on update handler (check for scaling, CRTC coverage,
   subpixel positioning)
 - Pass proper panning parameters to modeset interface
 - Disallow disabling primary plane (and thus CRTC) if other planes are
   still active on the CRTC.
 - Use a minimal format list that should work on all hardware/drivers.
   Drivers may call this function with a more accurate plane list to
   enable additional formats they can support.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/Makefile

@@ -13,7 +13,8 @@ drm-y       :=	drm_auth.o drm_buffer.o drm_bufs.o drm_cache.o \
 		drm_crtc.o drm_modes.o drm_edid.o \
 		drm_info.o drm_debugfs.o drm_encoder_slave.o \
 		drm_trace_points.o drm_global.o drm_prime.o \
-		drm_rect.o drm_vma_manager.o drm_flip_work.o
+		drm_rect.o drm_vma_manager.o drm_flip_work.o \
+		drm_plane_helper.o
 
 drm-$(CONFIG_COMPAT) += drm_ioc32.o
 drm-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_gem_cma_helper.o

include/drm/drm_plane_helper.h

+/*
+ * Copyright (C) 2011-2013 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef DRM_PLANE_HELPER_H
+#define DRM_PLANE_HELPER_H
+
+/**
+ * DOC: plane helpers
+ *
+ * Helper functions to assist with creation and handling of CRTC primary
+ * planes.
+ */
+
+extern int drm_primary_helper_update(struct drm_plane *plane,
+				     struct drm_crtc *crtc,
+				     struct drm_framebuffer *fb,
+				     int crtc_x, int crtc_y,
+				     unsigned int crtc_w, unsigned int crtc_h,
+				     uint32_t src_x, uint32_t src_y,
+				     uint32_t src_w, uint32_t src_h);
+extern int drm_primary_helper_disable(struct drm_plane *plane);
+extern void drm_primary_helper_destroy(struct drm_plane *plane);
+extern const struct drm_plane_funcs drm_primary_helper_funcs;
+extern struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev,
+							 uint32_t *formats,
+							 int num_formats);
+
+
+#endif