Provides helper functions for drivers that have a simple display
pipeline. Plane, crtc and encoder are collapsed into one entity.
Cc: jsarha@xxxxxx
Signed-off-by: Noralf Trønnes <noralf@xxxxxxxxxxx>
---
Changes since v3:
- (struct drm_simple_display_pipe *)->funcs should be const
Changes since v2:
- Drop Kconfig knob DRM_KMS_HELPER
- Expand documentation
Changes since v1:
- Add DOC header and add to gpu.tmpl
- Fix docs: @funcs is optional, "negative error code",
"This hook is optional."
- Add checks to drm_simple_kms_plane_atomic_check()
Documentation/DocBook/gpu.tmpl | 6 +
drivers/gpu/drm/Makefile | 2 +-
drivers/gpu/drm/drm_simple_kms_helper.c | 208 ++++++++++++++++++++++++++++++++
include/drm/drm_simple_kms_helper.h | 94 +++++++++++++++
4 files changed, 309 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/drm_simple_kms_helper.c
create mode 100644 include/drm/drm_simple_kms_helper.h
diff --git a/Documentation/DocBook/gpu.tmpl b/Documentation/DocBook/gpu.tmpl
index 4a0c599..cf3f5a8 100644
--- a/Documentation/DocBook/gpu.tmpl
+++ b/Documentation/DocBook/gpu.tmpl
@@ -1693,6 +1693,12 @@ void intel_crt_init(struct drm_device *dev)
!Edrivers/gpu/drm/drm_panel.c
!Pdrivers/gpu/drm/drm_panel.c drm panel
</sect2>
+ <sect2>
+ <title>Simple KMS Helper Reference</title>
+!Iinclude/drm/drm_simple_kms_helper.h
+!Edrivers/gpu/drm/drm_simple_kms_helper.c
+!Pdrivers/gpu/drm/drm_simple_kms_helper.c overview
+ </sect2>
</sect1>
<!-- Internals: kms properties -->
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 2bd3e5a..31b85df5 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -23,7 +23,7 @@ drm-$(CONFIG_AGP) += drm_agpsupport.o
drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o \
drm_plane_helper.o drm_dp_mst_topology.o drm_atomic_helper.o \
- drm_kms_helper_common.o
+ drm_kms_helper_common.o drm_simple_kms_helper.o
drm_kms_helper-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o
diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c
new file mode 100644
index 0000000..d45417a
--- /dev/null
+++ b/drivers/gpu/drm/drm_simple_kms_helper.c
@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_plane_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <linux/slab.h>
+
+/**
+ * DOC: overview
+ *
+ * This helper library provides helpers for drivers for simple display
+ * hardware.
+ *
+ * drm_simple_display_pipe_init() initializes a simple display pipeline
+ * which has only one full-screen scanout buffer feeding one output. The
+ * pipeline is represented by struct &drm_simple_display_pipe and binds
+ * together &drm_plane, &drm_crtc and &drm_encoder structures into one fixed
+ * entity. Some flexibility for code reuse is provided through a separately
+ * allocated &drm_connector object and supporting optional &drm_bridge
+ * encoder drivers.
+ */
+
+static const struct drm_encoder_funcs drm_simple_kms_encoder_funcs = {
+ .destroy = drm_encoder_cleanup,
+};
+
+static void drm_simple_kms_crtc_enable(struct drm_crtc *crtc)
+{
+ struct drm_simple_display_pipe *pipe;
+
+ pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
+ if (!pipe->funcs || !pipe->funcs->enable)
+ return;
+
+ pipe->funcs->enable(pipe, crtc->state);
+}
+
+static void drm_simple_kms_crtc_disable(struct drm_crtc *crtc)
+{
+ struct drm_simple_display_pipe *pipe;
+
+ pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
+ if (!pipe->funcs || !pipe->funcs->disable)
+ return;
+
+ pipe->funcs->disable(pipe);
+}
+
+static const struct drm_crtc_helper_funcs drm_simple_kms_crtc_helper_funcs = {
+ .disable = drm_simple_kms_crtc_disable,
+ .enable = drm_simple_kms_crtc_enable,
+};
+
+static const struct drm_crtc_funcs drm_simple_kms_crtc_funcs = {
+ .reset = drm_atomic_helper_crtc_reset,
+ .destroy = drm_crtc_cleanup,
+ .set_config = drm_atomic_helper_set_config,
+ .page_flip = drm_atomic_helper_page_flip,
+ .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+};
+
+static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane,
+ struct drm_plane_state *plane_state)
+{
+ struct drm_rect src = {
+ .x1 = plane_state->src_x,
+ .y1 = plane_state->src_y,
+ .x2 = plane_state->src_x + plane_state->src_w,
+ .y2 = plane_state->src_y + plane_state->src_h,
+ };
+ struct drm_rect dest = {
+ .x1 = plane_state->crtc_x,
+ .y1 = plane_state->crtc_y,
+ .x2 = plane_state->crtc_x + plane_state->crtc_w,
+ .y2 = plane_state->crtc_y + plane_state->crtc_h,
+ };
+ struct drm_rect clip = { 0 };
+ struct drm_simple_display_pipe *pipe;
+ struct drm_crtc_state *crtc_state;
+ bool visible;
+ int ret;
+
+ pipe = container_of(plane, struct drm_simple_display_pipe, plane);
+ crtc_state = drm_atomic_get_existing_crtc_state(plane_state->state,
+ &pipe->crtc);
+ if (crtc_state->enable != !!plane_state->crtc)
+ return -EINVAL; /* plane must match crtc enable state */
+
+ if (!crtc_state->enable)
+ return 0; /* nothing to check when disabling or disabled */
+
+ clip.x2 = crtc_state->adjusted_mode.hdisplay;
+ clip.y2 = crtc_state->adjusted_mode.vdisplay;
+ ret = drm_plane_helper_check_update(plane, &pipe->crtc,
+ plane_state->fb,
+ &src, &dest, &clip,
+ DRM_PLANE_HELPER_NO_SCALING,
+ DRM_PLANE_HELPER_NO_SCALING,
+ false, true, &visible);
+ if (ret)
+ return ret;
+
+ if (!visible)
+ return -EINVAL;
+
+ if (!pipe->funcs || !pipe->funcs->check)
+ return 0;
+
+ return pipe->funcs->check(pipe, plane_state, crtc_state);
+}
