drm: add Atmel HLCDC Display Controller support

The Atmel HLCDC (HLCD Controller) IP available on some Atmel SoCs (i.e.
at91sam9n12, at91sam9x5 family or sama5d3 family) provides a display
controller device.

This display controller supports at least one primary plane and might
provide several overlays and an hardware cursor depending on the IP
version.

At the moment, this driver only implements an RGB connector to interface
with LCD panels, but support for other kind of external devices might be
added later.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Tested-by: Anthony Harivel <anthony.harivel@emtrion.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

drivers/gpu/drm/Kconfig

@@ -183,6 +183,8 @@ source "drivers/gpu/drm/cirrus/Kconfig"
 
 source "drivers/gpu/drm/armada/Kconfig"
 
+source "drivers/gpu/drm/atmel-hlcdc/Kconfig"
+
 source "drivers/gpu/drm/rcar-du/Kconfig"
 
 source "drivers/gpu/drm/shmobile/Kconfig"

drivers/gpu/drm/Makefile

@@ -54,6 +54,7 @@ obj-$(CONFIG_DRM_GMA500) += gma500/
 obj-$(CONFIG_DRM_UDL) += udl/
 obj-$(CONFIG_DRM_AST) += ast/
 obj-$(CONFIG_DRM_ARMADA) += armada/
+obj-$(CONFIG_DRM_ATMEL_HLCDC)	+= atmel-hlcdc/
 obj-$(CONFIG_DRM_RCAR_DU) += rcar-du/
 obj-$(CONFIG_DRM_SHMOBILE) +=shmobile/
 obj-$(CONFIG_DRM_OMAP)	+= omapdrm/

drivers/gpu/drm/atmel-hlcdc/Kconfig

+config DRM_ATMEL_HLCDC
+	tristate "DRM Support for ATMEL HLCDC Display Controller"
+	depends on DRM && OF && COMMON_CLK && MFD_ATMEL_HLCDC
+	select DRM_GEM_CMA_HELPER
+	select DRM_KMS_HELPER
+	select DRM_KMS_FB_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_PANEL
+	help
+	  Choose this option if you have an ATMEL SoC with an HLCDC display
+	  controller (i.e. at91sam9n12, at91sam9x5 family or sama5d3 family).

drivers/gpu/drm/atmel-hlcdc/Makefile

+atmel-hlcdc-dc-y := atmel_hlcdc_crtc.o \
+		atmel_hlcdc_dc.o \
+		atmel_hlcdc_layer.o \
+		atmel_hlcdc_output.o \
+		atmel_hlcdc_plane.o
+
+obj-$(CONFIG_DRM_ATMEL_HLCDC)	+= atmel-hlcdc-dc.o

drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h

+/*
+ * Copyright (C) 2014 Traphandler
+ * Copyright (C) 2014 Free Electrons
+ * Copyright (C) 2014 Atmel
+ *
+ * Author: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
+ * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef DRM_ATMEL_HLCDC_H
+#define DRM_ATMEL_HLCDC_H
+
+#include <linux/clk.h>
+#include <linux/irqdomain.h>
+#include <linux/pwm.h>
+
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_panel.h>
+#include <drm/drmP.h>
+
+#include "atmel_hlcdc_layer.h"
+
+#define ATMEL_HLCDC_MAX_LAYERS		5
+
+/**
+ * Atmel HLCDC Display Controller description structure.
+ *
+ * This structure describe the HLCDC IP capabilities and depends on the
+ * HLCDC IP version (or Atmel SoC family).
+ *
+ * @min_width: minimum width supported by the Display Controller
+ * @min_height: minimum height supported by the Display Controller
+ * @max_width: maximum width supported by the Display Controller
+ * @max_height: maximum height supported by the Display Controller
+ * @layers: a layer description table describing available layers
+ * @nlayers: layer description table size
+ */
+struct atmel_hlcdc_dc_desc {
+	int min_width;
+	int min_height;
+	int max_width;
+	int max_height;
+	const struct atmel_hlcdc_layer_desc *layers;
+	int nlayers;
+};
+
+/**
+ * Atmel HLCDC Plane properties.
+ *
+ * This structure stores plane property definitions.
+ *
+ * @alpha: alpha blending (or transparency) property
+ * @rotation: rotation property
+ */
+struct atmel_hlcdc_plane_properties {
+	struct drm_property *alpha;
+	struct drm_property *rotation;
+};
+
+/**
+ * Atmel HLCDC Plane.
+ *
+ * @base: base DRM plane structure
+ * @layer: HLCDC layer structure
+ * @properties: pointer to the property definitions structure
+ * @rotation: current rotation status
+ */
+struct atmel_hlcdc_plane {
+	struct drm_plane base;
+	struct atmel_hlcdc_layer layer;
+	struct atmel_hlcdc_plane_properties *properties;
+	unsigned int rotation;
+};
+
+static inline struct atmel_hlcdc_plane *
+drm_plane_to_atmel_hlcdc_plane(struct drm_plane *p)
+{
+	return container_of(p, struct atmel_hlcdc_plane, base);
+}
+
+static inline struct atmel_hlcdc_plane *
+atmel_hlcdc_layer_to_plane(struct atmel_hlcdc_layer *l)
+{
+	return container_of(l, struct atmel_hlcdc_plane, layer);
+}
+
+/**
+ * Atmel HLCDC Plane update request structure.
+ *
+ * @crtc_x: x position of the plane relative to the CRTC
+ * @crtc_y: y position of the plane relative to the CRTC
+ * @crtc_w: visible width of the plane
+ * @crtc_h: visible height of the plane
+ * @src_x: x buffer position
+ * @src_y: y buffer position
+ * @src_w: buffer width
+ * @src_h: buffer height
+ * @fb: framebuffer object object
+ * @bpp: bytes per pixel deduced from pixel_format
+ * @offsets: offsets to apply to the GEM buffers
+ * @xstride: value to add to the pixel pointer between each line
+ * @pstride: value to add to the pixel pointer between each pixel
+ * @nplanes: number of planes (deduced from pixel_format)
+ */
+struct atmel_hlcdc_plane_update_req {
+	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;
+	struct drm_framebuffer *fb;
+
+	/* These fields are private and should not be touched */
+	int bpp[ATMEL_HLCDC_MAX_PLANES];
+	unsigned int offsets[ATMEL_HLCDC_MAX_PLANES];
+	int xstride[ATMEL_HLCDC_MAX_PLANES];
+	int pstride[ATMEL_HLCDC_MAX_PLANES];
+	int nplanes;
+};
+
+/**
+ * Atmel HLCDC Planes.
+ *
+ * This structure stores the instantiated HLCDC Planes and can be accessed by
+ * the HLCDC Display Controller or the HLCDC CRTC.
+ *
+ * @primary: primary plane
+ * @cursor: hardware cursor plane
+ * @overlays: overlay plane table
+ * @noverlays: number of overlay planes
+ */
+struct atmel_hlcdc_planes {
+	struct atmel_hlcdc_plane *primary;
+	struct atmel_hlcdc_plane *cursor;
+	struct atmel_hlcdc_plane **overlays;
+	int noverlays;
+};
+
+/**
+ * Atmel HLCDC Display Controller.
+ *
+ * @desc: HLCDC Display Controller description
+ * @hlcdc: pointer to the atmel_hlcdc structure provided by the MFD device
+ * @fbdev: framebuffer device attached to the Display Controller
+ * @crtc: CRTC provided by the display controller
+ * @planes: instantiated planes
+ * @layers: active HLCDC layer
+ * @wq: display controller workqueue
+ */
+struct atmel_hlcdc_dc {
+	const struct atmel_hlcdc_dc_desc *desc;
+	struct atmel_hlcdc *hlcdc;
+	struct drm_fbdev_cma *fbdev;
+	struct drm_crtc *crtc;
+	struct atmel_hlcdc_planes *planes;
+	struct atmel_hlcdc_layer *layers[ATMEL_HLCDC_MAX_LAYERS];
+	struct workqueue_struct *wq;
+};
+
+extern struct atmel_hlcdc_formats atmel_hlcdc_plane_rgb_formats;
+extern struct atmel_hlcdc_formats atmel_hlcdc_plane_rgb_and_yuv_formats;
+
+int atmel_hlcdc_dc_mode_valid(struct atmel_hlcdc_dc *dc,
+			      struct drm_display_mode *mode);
+
+struct atmel_hlcdc_planes *
+atmel_hlcdc_create_planes(struct drm_device *dev);
+
+int atmel_hlcdc_plane_prepare_update_req(struct drm_plane *p,
+				struct atmel_hlcdc_plane_update_req *req,
+				const struct drm_display_mode *mode);
+
+int atmel_hlcdc_plane_apply_update_req(struct drm_plane *p,
+				struct atmel_hlcdc_plane_update_req *req);
+
+int atmel_hlcdc_plane_update_with_mode(struct drm_plane *p,
+				       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,
+				       const struct drm_display_mode *mode);
+
+void atmel_hlcdc_crtc_irq(struct drm_crtc *c);
+
+void atmel_hlcdc_crtc_cancel_page_flip(struct drm_crtc *crtc,
+				       struct drm_file *file);
+
+int atmel_hlcdc_crtc_create(struct drm_device *dev);
+
+int atmel_hlcdc_create_outputs(struct drm_device *dev);
+
+#endif /* DRM_ATMEL_HLCDC_H */

drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c

+/*
+ * Copyright (C) 2014 Traphandler
+ * Copyright (C) 2014 Free Electrons
+ * Copyright (C) 2014 Atmel
+ *
+ * Author: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
+ * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/of_graph.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_panel.h>
+
+#include "atmel_hlcdc_dc.h"
+
+/**
+ * Atmel HLCDC RGB output mode
+ */
+enum atmel_hlcdc_connector_rgb_mode {
+	ATMEL_HLCDC_CONNECTOR_RGB444,
+	ATMEL_HLCDC_CONNECTOR_RGB565,
+	ATMEL_HLCDC_CONNECTOR_RGB666,
+	ATMEL_HLCDC_CONNECTOR_RGB888,
+};
+
+/**
+ * Atmel HLCDC RGB connector structure
+ *
+ * This structure stores RGB slave device information.
+ *
+ * @connector: DRM connector
+ * @encoder: DRM encoder
+ * @dc: pointer to the atmel_hlcdc_dc structure
+ * @dpms: current DPMS mode
+ */
+struct atmel_hlcdc_rgb_output {
+	struct drm_connector connector;
+	struct drm_encoder encoder;
+	struct atmel_hlcdc_dc *dc;
+	int dpms;
+};
+
+static inline struct atmel_hlcdc_rgb_output *
+drm_connector_to_atmel_hlcdc_rgb_output(struct drm_connector *connector)
+{
+	return container_of(connector, struct atmel_hlcdc_rgb_output,
+			    connector);
+}
+
+static inline struct atmel_hlcdc_rgb_output *
+drm_encoder_to_atmel_hlcdc_rgb_output(struct drm_encoder *encoder)
+{
+	return container_of(encoder, struct atmel_hlcdc_rgb_output, encoder);
+}
+
+/**
+ * Atmel HLCDC Panel device structure
+ *
+ * This structure is specialization of the slave device structure to
+ * interface with drm panels.
+ *
+ * @base: base slave device fields
+ * @panel: drm panel attached to this slave device
+ */
+struct atmel_hlcdc_panel {
+	struct atmel_hlcdc_rgb_output base;
+	struct drm_panel *panel;
+};
+
+static inline struct atmel_hlcdc_panel *
+atmel_hlcdc_rgb_output_to_panel(struct atmel_hlcdc_rgb_output *output)
+{
+	return container_of(output, struct atmel_hlcdc_panel, base);
+}
+
+static void atmel_hlcdc_panel_encoder_dpms(struct drm_encoder *encoder,
+					   int mode)
+{
+	struct atmel_hlcdc_rgb_output *rgb =
+			drm_encoder_to_atmel_hlcdc_rgb_output(encoder);
+	struct atmel_hlcdc_panel *panel = atmel_hlcdc_rgb_output_to_panel(rgb);
+
+	if (mode != DRM_MODE_DPMS_ON)
+		mode = DRM_MODE_DPMS_OFF;
+
+	if (mode == rgb->dpms)
+		return;
+
+	if (mode != DRM_MODE_DPMS_ON)
+		drm_panel_disable(panel->panel);
+	else
+		drm_panel_enable(panel->panel);
+
+	rgb->dpms = mode;
+}
+
+static bool
+atmel_hlcdc_panel_encoder_mode_fixup(struct drm_encoder *encoder,
+				     const struct drm_display_mode *mode,
+				     struct drm_display_mode *adjusted)
+{
+	return true;
+}
+
+static void atmel_hlcdc_panel_encoder_prepare(struct drm_encoder *encoder)
+{
+	atmel_hlcdc_panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
+}
+
+static void atmel_hlcdc_panel_encoder_commit(struct drm_encoder *encoder)
+{
+	atmel_hlcdc_panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
+}
+
+static void
+atmel_hlcdc_rgb_encoder_mode_set(struct drm_encoder *encoder,
+				 struct drm_display_mode *mode,
+				 struct drm_display_mode *adjusted)
+{
+	struct atmel_hlcdc_rgb_output *rgb =
+			drm_encoder_to_atmel_hlcdc_rgb_output(encoder);
+	struct drm_display_info *info = &rgb->connector.display_info;
+	unsigned int cfg;
+
+	cfg = 0;
+
+	if (info->num_bus_formats) {
+		switch (info->bus_formats[0]) {
+		case MEDIA_BUS_FMT_RGB666_1X18:
+			cfg |= ATMEL_HLCDC_CONNECTOR_RGB666 << 8;
+			break;
+		case MEDIA_BUS_FMT_RGB888_1X24:
+			cfg |= ATMEL_HLCDC_CONNECTOR_RGB888 << 8;
+			break;
+		default:
+			break;
+		}
+	}
+
+	regmap_update_bits(rgb->dc->hlcdc->regmap, ATMEL_HLCDC_CFG(5),
+			   ATMEL_HLCDC_MODE_MASK,
+			   cfg);
+}
+
+static struct drm_encoder_helper_funcs atmel_hlcdc_panel_encoder_helper_funcs = {
+	.dpms = atmel_hlcdc_panel_encoder_dpms,
+	.mode_fixup = atmel_hlcdc_panel_encoder_mode_fixup,
+	.prepare = atmel_hlcdc_panel_encoder_prepare,
+	.commit = atmel_hlcdc_panel_encoder_commit,
+	.mode_set = atmel_hlcdc_rgb_encoder_mode_set,
+};
+
+static void atmel_hlcdc_rgb_encoder_destroy(struct drm_encoder *encoder)
+{
+	drm_encoder_cleanup(encoder);
+	memset(encoder, 0, sizeof(*encoder));
+}
+
+static const struct drm_encoder_funcs atmel_hlcdc_panel_encoder_funcs = {
+	.destroy = atmel_hlcdc_rgb_encoder_destroy,
+};
+
+static int atmel_hlcdc_panel_get_modes(struct drm_connector *connector)
+{
+	struct atmel_hlcdc_rgb_output *rgb =
+			drm_connector_to_atmel_hlcdc_rgb_output(connector);
+	struct atmel_hlcdc_panel *panel = atmel_hlcdc_rgb_output_to_panel(rgb);
+
+	return panel->panel->funcs->get_modes(panel->panel);
+}
+
+static int atmel_hlcdc_rgb_mode_valid(struct drm_connector *connector,
+				      struct drm_display_mode *mode)
+{
+	struct atmel_hlcdc_rgb_output *rgb =
+			drm_connector_to_atmel_hlcdc_rgb_output(connector);
+
+	return atmel_hlcdc_dc_mode_valid(rgb->dc, mode);
+}
+
+
+
+static struct drm_encoder *
+atmel_hlcdc_rgb_best_encoder(struct drm_connector *connector)
+{
+	struct atmel_hlcdc_rgb_output *rgb =
+			drm_connector_to_atmel_hlcdc_rgb_output(connector);
+
+	return &rgb->encoder;
+}
+
+static struct drm_connector_helper_funcs atmel_hlcdc_panel_connector_helper_funcs = {
+	.get_modes = atmel_hlcdc_panel_get_modes,
+	.mode_valid = atmel_hlcdc_rgb_mode_valid,
+	.best_encoder = atmel_hlcdc_rgb_best_encoder,
+};
+
+static enum drm_connector_status
+atmel_hlcdc_panel_connector_detect(struct drm_connector *connector, bool force)
+{
+	return connector_status_connected;
+}
+
+static void
+atmel_hlcdc_panel_connector_destroy(struct drm_connector *connector)
+{
+	struct atmel_hlcdc_rgb_output *rgb =
+			drm_connector_to_atmel_hlcdc_rgb_output(connector);
+	struct atmel_hlcdc_panel *panel = atmel_hlcdc_rgb_output_to_panel(rgb);
+
+	drm_panel_detach(panel->panel);
+	drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs atmel_hlcdc_panel_connector_funcs = {
+	.dpms = drm_helper_connector_dpms,
+	.detect = atmel_hlcdc_panel_connector_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = atmel_hlcdc_panel_connector_destroy,
+};
+
+static int atmel_hlcdc_create_panel_output(struct drm_device *dev,
+					   struct of_endpoint *ep)
+{
+	struct atmel_hlcdc_dc *dc = dev->dev_private;
+	struct device_node *np;
+	struct drm_panel *p = NULL;
+	struct atmel_hlcdc_panel *panel;
+	int ret;
+
+	np = of_graph_get_remote_port_parent(ep->local_node);
+	if (!np)
+		return -EINVAL;
+
+	p = of_drm_find_panel(np);
+	of_node_put(np);
+
+	if (!p)
+		return -EPROBE_DEFER;
+
+	panel = devm_kzalloc(dev->dev, sizeof(*panel), GFP_KERNEL);
+	if (!panel)
+		return -EINVAL;
+
+	panel->base.dpms = DRM_MODE_DPMS_OFF;
+
+	panel->base.dc = dc;
+
+	drm_encoder_helper_add(&panel->base.encoder,
+			       &atmel_hlcdc_panel_encoder_helper_funcs);
+	ret = drm_encoder_init(dev, &panel->base.encoder,
+			       &atmel_hlcdc_panel_encoder_funcs,
+			       DRM_MODE_ENCODER_LVDS);
+	if (ret)
+		return ret;
+
+	panel->base.connector.dpms = DRM_MODE_DPMS_OFF;
+	panel->base.connector.polled = DRM_CONNECTOR_POLL_CONNECT;
+	drm_connector_helper_add(&panel->base.connector,
+				 &atmel_hlcdc_panel_connector_helper_funcs);
+	ret = drm_connector_init(dev, &panel->base.connector,
+				 &atmel_hlcdc_panel_connector_funcs,
+				 DRM_MODE_CONNECTOR_LVDS);
+	if (ret)
+		goto err_encoder_cleanup;
+
+	drm_mode_connector_attach_encoder(&panel->base.connector,
+					  &panel->base.encoder);
+	panel->base.encoder.possible_crtcs = 0x1;
+
+	drm_panel_attach(p, &panel->base.connector);
+	panel->panel = p;
+
+	return 0;
+
+err_encoder_cleanup:
+	drm_encoder_cleanup(&panel->base.encoder);
+
+	return ret;
+}
+
+int atmel_hlcdc_create_outputs(struct drm_device *dev)
+{
+	struct device_node *port_np, *np;
+	struct of_endpoint ep;
+	int ret;
+
+	port_np = of_get_child_by_name(dev->dev->of_node, "port");
+	if (!port_np)
+		return -EINVAL;
+
+	np = of_get_child_by_name(port_np, "endpoint");
+	of_node_put(port_np);
+
+	if (!np)
+		return -EINVAL;
+
+	ret = of_graph_parse_endpoint(np, &ep);
+	of_node_put(port_np);
+
+	if (ret)
+		return ret;
+
+	/* We currently only support panel output */
+	return atmel_hlcdc_create_panel_output(dev, &ep);
+}