[PATCH v2 05/21] [media] imx: Add i.MX SoC wide media device driver

[Philipp Zabel <p.zabel@pengutronix.de>]

This driver registers a single, SoC wide media device, which all entities
in the media graph can be registered to. It is probed from device tree
using a capture-subsystem node, listing the IPUv3 input ports, similarly
to the already existing display-subsystem node that lists the IPUv3 output
ports.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 .../devicetree/bindings/media/fsl-imx-capture.txt  |  25 +++
 drivers/media/platform/Kconfig                     |   2 +
 drivers/media/platform/Makefile                    |   1 +
 drivers/media/platform/imx/Kconfig                 |   7 +
 drivers/media/platform/imx/Makefile                |   1 +
 drivers/media/platform/imx/imx-media.c             | 249 +++++++++++++++++++++
 6 files changed, 285 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/fsl-imx-capture.txt
 create mode 100644 drivers/media/platform/imx/Kconfig
 create mode 100644 drivers/media/platform/imx/Makefile
 create mode 100644 drivers/media/platform/imx/imx-media.c

diff --git a/Documentation/devicetree/bindings/media/fsl-imx-capture.txt b/Documentation/devicetree/bindings/media/fsl-imx-capture.txt
new file mode 100644
index 0000000..5805331
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/fsl-imx-capture.txt
@@ -0,0 +1,25 @@
+Freescale i.MX IPUv3 capture subsystem
+======================================
+
+The i.MX5/6 IPUv3 capture subsystem consists of one or two IPUs and all
+external subdevices connected to the IPU CSI input ports. On i.MX5 these
+are only external subdevices. On i.MX6, there are additional SoC internal
+multiplexers and a MIPI CSI-2 bridge connected to the CSI input ports via
+of_graph bindings.
+
+On i.MX6 variants with two IPUs, either a single capture subsystem node may be
+defined, containing all CSI ports, or two separate capture subsystem nodes may
+be defined, each containing the CSI ports of a single IPU. In the latter case
+there must be no external of_graph links between the two subsystems.
+
+Required properties:
+- compatible: should be "fsl,imx-capture-subsystem"
+- ports: should contain a list of phandles pointing to the capture interface
+  ports of IPU devices
+
+Example:
+
+capture-subsystem {
+        compatible = "fsl,imx-capture-subsystem";
+        ports = <&ipu1_csi0>, <&ipu1_csi1>, <&ipu2_csi0>, <&ipu2_csi1>;
+};
diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index ce4a96f..105bf57 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -29,6 +29,8 @@ config VIDEO_VIA_CAMERA
 
 source "drivers/media/platform/davinci/Kconfig"
 
+source "drivers/media/platform/imx/Kconfig"
+
 source "drivers/media/platform/omap/Kconfig"
 
 source "drivers/media/platform/blackfin/Kconfig"
diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
index 40b18d1..f7f9008 100644
--- a/drivers/media/platform/Makefile
+++ b/drivers/media/platform/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_VIDEO_RENESAS_FCP) 	+= rcar-fcp.o
 obj-$(CONFIG_VIDEO_RENESAS_JPU) 	+= rcar_jpu.o
 obj-$(CONFIG_VIDEO_RENESAS_VSP1)	+= vsp1/
 
+obj-y	+= imx/
 obj-y	+= omap/
 
 obj-$(CONFIG_VIDEO_AM437X_VPFE)		+= am437x/
diff --git a/drivers/media/platform/imx/Kconfig b/drivers/media/platform/imx/Kconfig
new file mode 100644
index 0000000..3bd699c
--- /dev/null
+++ b/drivers/media/platform/imx/Kconfig
@@ -0,0 +1,7 @@
+config MEDIA_IMX
+	tristate "Multimedia Support for Freescale i.MX"
+	depends on MEDIA_CONTROLLER
+	default y if IMX_IPUV3_CORE
+	---help---
+	  This driver provides a SoC wide media controller device that all
+	  multimedia components in i.MX5 and i.MX6 SoCs can register with.
diff --git a/drivers/media/platform/imx/Makefile b/drivers/media/platform/imx/Makefile
new file mode 100644
index 0000000..74bed76
--- /dev/null
+++ b/drivers/media/platform/imx/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_MEDIA_IMX)			+= imx-media.o
diff --git a/drivers/media/platform/imx/imx-media.c b/drivers/media/platform/imx/imx-media.c
new file mode 100644
index 0000000..1f1fab4
--- /dev/null
+++ b/drivers/media/platform/imx/imx-media.c
@@ -0,0 +1,249 @@
+/*
+ * i.MX V4L2 Capture Driver
+ *
+ * Copyright (C) 2016, Pengutronix, Philipp Zabel <kernel@pengutronix.de>
+ *
+ * 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/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <media/media-device.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-of.h>
+
+#define IMX_MEDIA_MAX_PORTS	4
+
+struct imx_media {
+	struct media_device mdev;
+	struct v4l2_device v4l2_dev;
+	struct v4l2_async_notifier subdev_notifier;
+	struct v4l2_async_subdev subdevs[IMX_MEDIA_MAX_PORTS];
+};
+
+static int v4l2_of_create_pad_link(struct v4l2_subdev *sd,
+				   struct v4l2_of_link *link)
+{
+	struct v4l2_subdev *remote_sd, *src_sd, *sink_sd;
+	struct media_link *mlink;
+	int src_port, sink_port;
+
+	if (link->local_port >= sd->entity.num_pads)
+		return -EINVAL;
+
+	remote_sd = v4l2_find_subdev_by_node(sd->v4l2_dev, link->remote_node);
+	if (!remote_sd)
+		return 0;
+
+	if (sd->entity.pads[link->local_port].flags & MEDIA_PAD_FL_SINK) {
+		src_sd = remote_sd;
+		src_port = link->remote_port;
+		sink_sd = sd;
+		sink_port = link->local_port;
+	} else {
+		src_sd = sd;
+		src_port = link->local_port;
+		sink_sd = remote_sd;
+		sink_port = link->remote_port;
+	}
+
+	mlink = media_entity_find_link(&src_sd->entity.pads[src_port],
+				       &sink_sd->entity.pads[sink_port]);
+	if (mlink)
+		return 0;
+
+	return media_create_pad_link(&src_sd->entity, src_port,
+			&sink_sd->entity, sink_port, 0);
+}
+
+static int imx_media_complete(struct v4l2_async_notifier *notifier)
+{
+	struct imx_media *im = container_of(notifier, struct imx_media,
+					    subdev_notifier);
+	struct media_device *mdev = &im->mdev;
+	struct v4l2_subdev *sd;
+	struct device_node *ep;
+
+	mutex_lock(&mdev->graph_mutex);
+
+	/*
+	 * Link all subdevices
+	 */
+	list_for_each_entry(sd, &notifier->done, async_list) {
+		struct v4l2_of_link link;
+		int ret;
+
+		/*
+		 * The IPU port nodes 0 and 1 correspond to the CSI subdevices.
+		 * We can't use for_each_endpoint_of_node here, which would
+		 * iterate over all endpoints of the IPU, including output ones.
+		 */
+		if (strcmp(sd->of_node->name, "port") == 0) {
+			/* There should be one endpoint in the CSI port */
+			ep = of_get_next_child(sd->of_node, NULL);
+			if (!ep)
+				continue;
+
+			ret = v4l2_of_parse_link(ep, &link);
+			if (ret) {
+				of_node_put(ep);
+				continue;
+			}
+
+			/*
+			 * The IPU port id in the device tree does not
+			 * correspond to the CSI pad id. Always connect
+			 * the source to the CSI input pad (pad 0).
+			 */
+			link.local_port = 0;
+
+			v4l2_of_create_pad_link(sd, &link);
+
+			v4l2_of_put_link(&link);
+
+			continue;
+		}
+
+		/*
+		 * TODO: for now assume that all subdevices other than CSI have
+		 * a 1:1 relationship between device_node and v4l2_subdev and
+		 * between of_graph port number and media_entity pad index.
+		 */
+		for_each_endpoint_of_node(sd->of_node, ep) {
+			ret = v4l2_of_parse_link(ep, &link);
+			if (ret)
+				continue;
+
+			v4l2_of_create_pad_link(sd, &link);
+
+			v4l2_of_put_link(&link);
+		}
+	}
+
+	mutex_unlock(&mdev->graph_mutex);
+
+	return v4l2_device_register_subdev_nodes(&im->v4l2_dev);
+}
+
+static void imx_media_register_notifier(struct imx_media *im)
+{
+	struct v4l2_async_notifier *notifier = &im->subdev_notifier;
+	struct v4l2_async_subdev *asd = &im->subdevs[0];
+	struct device_node *port;
+	int i;
+
+	/*
+	 * ports correspond to the CSI subdevices that terminate the media
+	 * pipelines.
+	 */
+	for (i = 0; i < IMX_MEDIA_MAX_PORTS; i++) {
+		port = of_parse_phandle(im->mdev.dev->of_node, "ports", i);
+		if (!port)
+			break;
+
+		if (!of_device_is_available(port->parent)) {
+			of_node_put(port);
+			continue;
+		}
+
+		asd[i].match_type = V4L2_ASYNC_MATCH_OF;
+		asd[i].match.of.node = port;
+		of_node_put(port);
+	}
+	notifier->num_subdevs = i;
+	notifier->subdevs = devm_kcalloc(im->mdev.dev, i,
+					 sizeof(*notifier->subdevs),
+					 GFP_KERNEL);
+	for (i = 0; i < notifier->num_subdevs; i++)
+		notifier->subdevs[i] = &im->subdevs[i];
+
+	notifier->complete = imx_media_complete;
+
+	v4l2_async_notifier_register(&im->v4l2_dev, notifier);
+}
+
+static int imx_media_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct media_device *mdev;
+	struct imx_media *im;
+	int ret;
+
+	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	im = devm_kzalloc(dev, sizeof(*im), GFP_KERNEL);
+	if (!im)
+		return -ENOMEM;
+
+	mdev = &im->mdev;
+	mdev->dev = dev;
+	strlcpy(mdev->model, "i.MX IPUv3", sizeof(mdev->model));
+	media_device_init(mdev);
+
+	im->v4l2_dev.mdev = mdev;
+	ret = v4l2_device_register(dev, &im->v4l2_dev);
+	if (ret) {
+		dev_err(dev, "Failed to register v4l2 device: %d\n", ret);
+		return ret;
+	}
+
+	imx_media_register_notifier(im);
+
+	ret = media_device_register(mdev);
+	if (ret) {
+		dev_err(dev, "Failed to register media controller device: %d\n",
+			ret);
+		goto err;
+	}
+
+	platform_set_drvdata(pdev, mdev);
+
+	return 0;
+
+err:
+	media_device_cleanup(mdev);
+	return ret;
+}
+
+static int imx_media_remove(struct platform_device *pdev)
+{
+	struct media_device *mdev = platform_get_drvdata(pdev);
+	struct imx_media *im = container_of(mdev, struct imx_media, mdev);
+
+	media_device_unregister(mdev);
+	v4l2_device_unregister(&im->v4l2_dev);
+	media_device_cleanup(mdev);
+
+	return 0;
+}
+
+static const struct of_device_id imx_media_dt_ids[] = {
+	{ .compatible = "fsl,imx-capture-subsystem", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, imx_media_dt_ids);
+
+static struct platform_driver imx_media_driver = {
+	.probe = imx_media_probe,
+	.remove = imx_media_remove,
+	.driver = {
+		.name = "imx-media",
+		.of_match_table = imx_media_dt_ids,
+	},
+};
+module_platform_driver(imx_media_driver);
+
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
+MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
+MODULE_DESCRIPTION("i.MX SoC wide media device");
+MODULE_LICENSE("GPL");
-- 
2.9.3