LF-811-1: drm/bridge: Add driver for legacy Freescale Seiko 43WVFIG a…

…dapter

This is an adapter card made for the 4.3", 800x480, LCD panel Seiko
43WVFIG. The LCD panel is a 24bit DPI bus, while the adapter card has
two ports: 18-bit and 24-bit data input. For the 18-bit data input, the
adapter card is demuxing some of the data lines, in order to feed all of
the 24 lines needed by the LCD.
This driver handles both this use-cases.

Signed-off-by: Robert Chiras <robert.chiras@nxp.com>

Documentation/devicetree/bindings/display/bridge/nxp,seiko-43wvfig.txt

@@ -0,0 +1,40 @@
+Legacy Freescale RA169Z20 adapter card for Seiko 43WVFIG panel, driver bindings
+
+This is an adapter card made for the 4.3", 800x480, LCD panel Seiko 43WVFIG.
+The LCD panel is a 24bit DPI bus, while the adapter card has two ports:
+18-bit and 24-bit data input. For the 18-bit data input, the adapter card
+is demuxing some of the data lines, in order to feed all of the 24 lines
+needed by the LCD.
+
+Required properties:
+- compatible: 	"nxp,seiko-43wvfig"
+- bus_mode:	must be one of <18> or <24>, depending on the input port
+		used (18-bit or 24-bit)
+- port:		input and output port nodes with endpoint definitions as
+		defined in Documentation/devicetree/bindings/graph.txt;
+		the input port should be connected to an lcd controller
+		while the output port should be connected to the Seiko
+		43wvfig LCD panel
+
+Example:
+	seiko_adapter: seiko-adapter {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "nxp,seiko-43wvfig";
+		bus_mode = <18>;
+
+		port@0 {
+			reg = <0>;
+			adapter_in: endpoint {
+				remote-endpoint = <&lcdif_out>;
+			};
+		};
+		port@1 {
+			reg = <1>;
+			adapter_out: endpoint {
+				remote-endpoint = <&panel_in>;
+			};
+		};
+	};
+
+-

drivers/gpu/drm/bridge/Kconfig

@@ -83,6 +83,11 @@ config DRM_SEC_MIPI_DSIM
 	help
 	  The Samsung MPI DSIM Bridge driver.
 
+config DRM_NXP_SEIKO_43WVFIG
+	tristate "Legacy Freescale Seiko 43WVFIG panel DPI adapter bridge"
+	select DRM_KMS_HELPER
+	select DRM_PANEL
+
 config DRM_NXP_PTN3460
 	tristate "NXP PTN3460 DP/LVDS bridge"
 	depends on OF

drivers/gpu/drm/bridge/Makefile

@@ -22,3 +22,4 @@ obj-y += cadence/
 obj-y += synopsys/
 obj-$(CONFIG_DRM_ITE_IT6263) += it6263.o
 obj-$(CONFIG_DRM_SEC_MIPI_DSIM) += sec-dsim.o
+obj-$(CONFIG_DRM_NXP_SEIKO_43WVFIG) += nxp-seiko-43wvfig.o

drivers/gpu/drm/bridge/nxp-seiko-43wvfig.c

@@ -0,0 +1,245 @@
+/*
+ * DRM driver for the legacy Freescale adapter card holding
+ * Seiko RA169Z20 43WVFIG LCD panel
+ *
+ * Copyright (C) 2018 NXP
+ *
+ * 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.
+ * 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.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_probe_helper.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/of_platform.h>
+
+struct seiko_adapter {
+	struct device		*dev;
+	struct drm_panel	*panel;
+	struct drm_bridge	bridge;
+	struct drm_connector	connector;
+
+	u32			bpc;
+	u32			bus_format;
+};
+
+static enum drm_connector_status seiko_adapter_connector_detect(
+	struct drm_connector *connector, bool force)
+{
+	return connector_status_connected;
+}
+
+static int seiko_adapter_connector_get_modes(struct drm_connector *connector)
+{
+	int num_modes;
+
+	struct seiko_adapter *adap = container_of(connector,
+						struct seiko_adapter,
+						connector);
+
+	num_modes = drm_panel_get_modes(adap->panel);
+
+	/*
+	 * The panel will populate the connector display_info properties with
+	 * fixed numbers, but we need to change them according to our
+	 * configuration.
+	 */
+	connector->display_info.bpc = adap->bpc;
+	drm_display_info_set_bus_formats(&connector->display_info,
+						 &adap->bus_format, 1);
+
+	return num_modes;
+}
+
+static const struct drm_connector_funcs seiko_adapter_connector_funcs = {
+	.detect = seiko_adapter_connector_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static const struct drm_connector_helper_funcs
+	seiko_adapter_connector_helper_funcs = {
+	.get_modes = seiko_adapter_connector_get_modes,
+};
+
+static int seiko_adapter_bridge_attach(struct drm_bridge *bridge)
+{
+	struct seiko_adapter *adap = bridge->driver_private;
+	struct device *dev = adap->dev;
+	struct drm_encoder *encoder = bridge->encoder;
+	struct drm_device *drm;
+	int ret = 0;
+
+	if (!encoder) {
+		DRM_DEV_ERROR(dev, "Parent encoder object not found\n");
+		return -ENODEV;
+	}
+
+	drm = encoder->dev;
+
+	/*
+	 * Create the connector for our panel
+	 */
+
+	ret = drm_connector_init(drm, &adap->connector,
+				 &seiko_adapter_connector_funcs,
+				 DRM_MODE_CONNECTOR_DPI);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "Failed to init drm connector: %d\n", ret);
+		return ret;
+	}
+
+	drm_connector_helper_add(&adap->connector,
+				 &seiko_adapter_connector_helper_funcs);
+
+	adap->connector.dpms = DRM_MODE_DPMS_OFF;
+	drm_connector_attach_encoder(&adap->connector, encoder);
+
+	ret = drm_panel_attach(adap->panel, &adap->connector);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "Failed to attach panel: %d\n", ret);
+		drm_connector_cleanup(&adap->connector);
+		return ret;
+	}
+
+	return ret;
+}
+
+static void seiko_adapter_bridge_detach(struct drm_bridge *bridge)
+{
+	struct seiko_adapter *adap = bridge->driver_private;
+
+	drm_panel_detach(adap->panel);
+	drm_connector_cleanup(&adap->connector);
+}
+
+static void seiko_adapter_bridge_enable(struct drm_bridge *bridge)
+{
+	struct seiko_adapter *adap = bridge->driver_private;
+	struct device *dev = adap->dev;
+
+	if (drm_panel_prepare(adap->panel)) {
+		DRM_DEV_ERROR(dev, "Failed to prepare panel\n");
+		return;
+	}
+
+	if (drm_panel_enable(adap->panel)) {
+		DRM_DEV_ERROR(dev, "Failed to enable panel\n");
+		drm_panel_unprepare(adap->panel);
+	}
+}
+
+static void seiko_adapter_bridge_disable(struct drm_bridge *bridge)
+{
+	struct seiko_adapter *adap = bridge->driver_private;
+	struct device *dev = adap->dev;
+
+	if (drm_panel_disable(adap->panel)) {
+		DRM_DEV_ERROR(dev, "failed to disable panel\n");
+		return;
+	}
+
+	if (drm_panel_unprepare(adap->panel))
+		DRM_DEV_ERROR(dev, "failed to unprepare panel\n");
+}
+
+static const struct drm_bridge_funcs seiko_adapter_bridge_funcs = {
+	.enable = seiko_adapter_bridge_enable,
+	.disable = seiko_adapter_bridge_disable,
+	.attach = seiko_adapter_bridge_attach,
+	.detach = seiko_adapter_bridge_detach,
+};
+
+static int seiko_adapter_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct seiko_adapter *adap;
+	struct device_node *remote;
+	u32 bus_mode;
+	int port;
+
+	adap = devm_kzalloc(dev, sizeof(*adap), GFP_KERNEL);
+	if (!adap)
+		return -ENOMEM;
+
+	of_property_read_u32(dev->of_node, "bus_mode", &bus_mode);
+	if (bus_mode != 18 && bus_mode != 24) {
+		dev_err(dev, "Invalid bus_mode: %d\n", bus_mode);
+		return -EINVAL;
+	}
+
+	switch (bus_mode) {
+	case 18:
+		adap->bpc = 6;
+		adap->bus_format = MEDIA_BUS_FMT_RGB666_1X18;
+		break;
+	case 24:
+		adap->bpc = 8;
+		adap->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+		break;
+	}
+
+	for (port = 0; port < 2; port++) {
+		remote = of_graph_get_remote_node(dev->of_node, port, -1);
+		if (!remote) {
+			dev_err(dev, "No remote for port %d\n", port);
+			return -ENODEV;
+		}
+		adap->panel = of_drm_find_panel(remote);
+		if (!IS_ERR(adap->panel))
+			break;
+	}
+	if (IS_ERR(adap->panel)) {
+		dev_err(dev, "No panel found: %ld\n", PTR_ERR(adap->panel));
+		return PTR_ERR(adap->panel);
+	}
+
+	adap->dev = dev;
+	adap->bridge.driver_private = adap;
+	adap->bridge.funcs = &seiko_adapter_bridge_funcs;
+	adap->bridge.of_node = dev->of_node;
+
+	drm_bridge_add(&adap->bridge);
+
+	return 0;
+}
+
+static int seiko_adapter_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id seiko_adapter_dt_ids[] = {
+	{ .compatible = "nxp,seiko-43wvfig" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, seiko_adapter_dt_ids);
+
+static struct platform_driver seiko_adapter_driver = {
+	.probe		= seiko_adapter_probe,
+	.remove		= seiko_adapter_remove,
+	.driver		= {
+		.of_match_table = seiko_adapter_dt_ids,
+		.name	= "nxp-seiko-adapter",
+	},
+};
+
+module_platform_driver(seiko_adapter_driver);
+
+MODULE_AUTHOR("NXP Semiconductor");
+MODULE_DESCRIPTION("Seiko 43WVFIG adapter card driver");
+MODULE_LICENSE("GPL");