Re: [RFC v2 2/5] video: panel: Add DPI panel support

From: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/video/display/Kconfig     |   13 +++
 drivers/video/display/Makefile    |    1 +
 drivers/video/display/panel-dpi.c |  147 +++++++++++++++++++++++++++++++++++++
 include/video/panel-dpi.h         |   24 ++++++
 4 files changed, 185 insertions(+), 0 deletions(-)
 create mode 100644 drivers/video/display/panel-dpi.c
 create mode 100644 include/video/panel-dpi.h

diff --git a/drivers/video/display/Kconfig b/drivers/video/display/Kconfig
index 1d533e7..0f9b990 100644
--- a/drivers/video/display/Kconfig
+++ b/drivers/video/display/Kconfig

@@ -2,3 +2,16 @@ menuconfig DISPLAY_CORE
 	tristate "Display Core"
 	---help---
 	  Support common display framework for graphics devices.
+
+if DISPLAY_CORE
+
+config DISPLAY_PANEL_DPI
+	tristate "DPI (Parallel) Display Panels"
+	---help---
+	  Support for simple digital (parallel) pixel interface panels. Those
+	  panels receive pixel data through a parallel bus and have no control
+	  bus.

+	  If you are in doubt, say N.
+
+endif # DISPLAY_CORE

diff --git a/drivers/video/display/Makefile b/drivers/video/display/Makefile
index bd93496..47978d4 100644
--- a/drivers/video/display/Makefile
+++ b/drivers/video/display/Makefile

@@ -1 +1,2 @@
 obj-$(CONFIG_DISPLAY_CORE) += display-core.o
+obj-$(CONFIG_DISPLAY_PANEL_DPI) += panel-dpi.o

diff --git a/drivers/video/display/panel-dpi.c b/drivers/video/display/panel-dpi.c
new file mode 100644
index 0000000..c56197a
--- /dev/null
+++ b/drivers/video/display/panel-dpi.c

@@ -0,0 +1,147 @@
+/*
+ * DPI Display Panel
+ *
+ * Copyright (C) 2012 Renesas Solutions Corp.
+ *
+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <video/display.h>
+#include <video/panel-dpi.h>
+
+struct panel_dpi {
+	struct display_entity entity;
+	const struct panel_dpi_platform_data *pdata;
+};
+
+#define to_panel_dpi(p)		container_of(p, struct panel_dpi, entity)
+
+static const struct display_entity_interface_params panel_dpi_params = {
+	.type = DISPLAY_ENTITY_INTERFACE_DPI,
+};
+
+static int panel_dpi_set_state(struct display_entity *entity,
+			       enum display_entity_state state)
+{
+	switch (state) {
+	case DISPLAY_ENTITY_STATE_OFF:
+	case DISPLAY_ENTITY_STATE_STANDBY:
+		display_entity_set_stream(entity->source,
+					  DISPLAY_ENTITY_STREAM_STOPPED);
+		break;
+
+	case DISPLAY_ENTITY_STATE_ON:
+		display_entity_set_stream(entity->source,
+					  DISPLAY_ENTITY_STREAM_CONTINUOUS);
+		break;
+	}
+
+	return 0;
+}
+
+static int panel_dpi_get_modes(struct display_entity *entity,
+			       const struct videomode **modes)
+{
+	struct panel_dpi *panel = to_panel_dpi(entity);
+
+	*modes = panel->pdata->mode;
+	return 1;
+}
+
+static int panel_dpi_get_size(struct display_entity *entity,
+			      unsigned int *width, unsigned int *height)
+{
+	struct panel_dpi *panel = to_panel_dpi(entity);
+
+	*width = panel->pdata->width;
+	*height = panel->pdata->height;
+	return 0;
+}
+
+static int panel_dpi_get_params(struct display_entity *entity,
+				struct display_entity_interface_params *params)
+{
+	*params = panel_dpi_params;
+	return 0;
+}
+
+static const struct display_entity_control_ops panel_dpi_control_ops = {
+	.set_state = panel_dpi_set_state,
+	.get_modes = panel_dpi_get_modes,
+	.get_size = panel_dpi_get_size,
+	.get_params = panel_dpi_get_params,
+};
+
+static void panel_dpi_release(struct display_entity *entity)
+{
+	struct panel_dpi *panel = to_panel_dpi(entity);
+
+	kfree(panel);
+}
+
+static int panel_dpi_remove(struct platform_device *pdev)
+{
+	struct panel_dpi *panel = platform_get_drvdata(pdev);
+
+	platform_set_drvdata(pdev, NULL);
+	display_entity_unregister(&panel->entity);
+
+	return 0;
+}
+
+static int __devinit panel_dpi_probe(struct platform_device *pdev)
+{
+	const struct panel_dpi_platform_data *pdata = pdev->dev.platform_data;
+	struct panel_dpi *panel;
+	int ret;
+
+	if (pdata = NULL)
+		return -ENODEV;
+
+	panel = kzalloc(sizeof(*panel), GFP_KERNEL);
+	if (panel = NULL)
+		return -ENOMEM;
+
+	panel->pdata = pdata;
+	panel->entity.dev = &pdev->dev;
+	panel->entity.release = panel_dpi_release;

+	panel->entity.ops.ctrl = &panel_dpi_control_ops;
+
+	ret = display_entity_register(&panel->entity);
+	if (ret < 0) {
+		kfree(panel);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, panel);
+
+	return 0;
+}
+
+static const struct dev_pm_ops panel_dpi_dev_pm_ops = {
+};
+
+static struct platform_driver panel_dpi_driver = {
+	.probe = panel_dpi_probe,
+	.remove = panel_dpi_remove,
+	.driver = {
+		.name = "panel_dpi",
+		.owner = THIS_MODULE,
+		.pm = &panel_dpi_dev_pm_ops,
+	},
+};
+
+module_platform_driver(panel_dpi_driver);
+
+MODULE_AUTHOR("Laurent Pinchart [off-list ref]");
+MODULE_DESCRIPTION("DPI Display Panel");
+MODULE_LICENSE("GPL");

diff --git a/include/video/panel-dpi.h b/include/video/panel-dpi.h
new file mode 100644
index 0000000..0547b4a
--- /dev/null
+++ b/include/video/panel-dpi.h

@@ -0,0 +1,24 @@
+/*
+ * DPI Display Panel
+ *
+ * Copyright (C) 2012 Renesas Solutions Corp.
+ *
+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.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.
+ */
+
+#ifndef __PANEL_DPI_H__
+#define __PANEL_DPI_H__
+
+#include <linux/videomode.h>
+
+struct panel_dpi_platform_data {
+	unsigned long width;		/* Panel width in mm */
+	unsigned long height;		/* Panel height in mm */
+	const struct videomode *mode;
+};
+
+#endif /* __PANEL_DPI_H__ */