media: imx: add csc/scaler mem2mem device

Add a single imx-media mem2mem video device that uses the IPU IC PP
(image converter post processing) task for scaling and colorspace
conversion.
On i.MX6Q/DL SoCs with two IPUs currently only the first IPU is used.

The hardware only supports writing to destination buffers up to
1024x1024 pixels in a single pass, arbitrary sizes can be achieved
by rendering multiple tiles per frame.

[slongerbeam@gmail.com: use ipu_image_convert_adjust(), fix
 device_run() error handling, add missing media-device header,
 unregister and remove the mem2mem device in error paths in
 imx_media_probe_complete() and in imx_media_remove(), updated
 for sync subdev registration]

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: correct two minor checkpatch issues]
[hverkuil-cisco@xs4all.nl: sparse warning: make imx6_media_probe_complete static]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/staging/media/imx/Kconfig

@@ -7,6 +7,7 @@ config VIDEO_IMX_MEDIA
 	depends on HAS_DMA
 	select VIDEOBUF2_DMA_CONTIG
 	select V4L2_FWNODE
+	select V4L2_MEM2MEM_DEV
 	help
 	  Say yes here to enable support for video4linux media controller
 	  driver for the i.MX5/6 SOC.

drivers/staging/media/imx/Makefile

@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 imx6-media-objs := imx-media-dev.o imx-media-internal-sd.o \
-	imx-ic-common.o imx-ic-prp.o imx-ic-prpencvf.o imx-media-vdic.o
+	imx-ic-common.o imx-ic-prp.o imx-ic-prpencvf.o imx-media-vdic.o \
+	imx-media-csc-scaler.o
 
 imx-media-common-objs := imx-media-capture.o imx-media-dev-common.o \
 	imx-media-of.o imx-media-utils.o

drivers/staging/media/imx/imx-media-dev.c

@@ -37,10 +37,35 @@ static int imx_media_subdev_bound(struct v4l2_async_notifier *notifier,
 	return 0;
 }
 
+/* async subdev complete notifier */
+static int imx6_media_probe_complete(struct v4l2_async_notifier *notifier)
+{
+	struct imx_media_dev *imxmd = notifier2dev(notifier);
+	int ret;
+
+	/* call the imx5/6/7 common probe completion handler */
+	ret = imx_media_probe_complete(notifier);
+	if (ret)
+		return ret;
+
+	mutex_lock(&imxmd->mutex);
+
+	imxmd->m2m_vdev = imx_media_csc_scaler_device_init(imxmd);
+	if (IS_ERR(imxmd->m2m_vdev)) {
+		ret = PTR_ERR(imxmd->m2m_vdev);
+		goto unlock;
+	}
+
+	ret = imx_media_csc_scaler_device_register(imxmd->m2m_vdev);
+unlock:
+	mutex_unlock(&imxmd->mutex);
+	return ret;
+}
+
 /* async subdev complete notifier */
 static const struct v4l2_async_notifier_operations imx_media_notifier_ops = {
 	.bound = imx_media_subdev_bound,
-	.complete = imx_media_probe_complete,
+	.complete = imx6_media_probe_complete,
 };
 
 static int imx_media_probe(struct platform_device *pdev)
@@ -85,6 +110,7 @@ static int imx_media_remove(struct platform_device *pdev)
 	v4l2_async_notifier_unregister(&imxmd->notifier);
 	imx_media_unregister_ipu_internal_subdevs(imxmd);
 	v4l2_async_notifier_cleanup(&imxmd->notifier);
+	imx_media_csc_scaler_device_unregister(imxmd->m2m_vdev);
 	media_device_unregister(&imxmd->md);
 	v4l2_device_unregister(&imxmd->v4l2_dev);
 	media_device_cleanup(&imxmd->md);

drivers/staging/media/imx/imx-media-internal-sd.c

@@ -210,6 +210,10 @@ int imx_media_register_ipu_internal_subdevs(struct imx_media_dev *imxmd,
 
 	mutex_lock(&imxmd->mutex);
 
+	/* record this IPU */
+	if (!imxmd->ipu[ipu_id])
+		imxmd->ipu[ipu_id] = ipu;
+
 	/* register the synchronous subdevs */
 	for (i = 0; i < NUM_IPU_SUBDEVS; i++) {
 		intsd = &int_subdev[i];

drivers/staging/media/imx/imx-media.h

@@ -136,9 +136,15 @@ struct imx_media_dev {
 	/* master video device list */
 	struct list_head vdev_list;
 
+	/* IPUs this media driver control, valid after subdevs bound */
+	struct ipu_soc *ipu[2];
+
 	/* for async subdev registration */
 	struct v4l2_async_notifier notifier;
 
+	/* IC scaler/CSC mem2mem video device */
+	struct imx_media_video_dev *m2m_vdev;
+
 	/* the IPU internal subdev's registered synchronously */
 	struct v4l2_subdev *sync_sd[2][NUM_IPU_SUBDEVS];
 };
@@ -269,6 +275,12 @@ struct imx_media_buffer *
 imx_media_capture_device_next_buf(struct imx_media_video_dev *vdev);
 void imx_media_capture_device_error(struct imx_media_video_dev *vdev);
 
+/* imx-media-csc-scaler.c */
+struct imx_media_video_dev *
+imx_media_csc_scaler_device_init(struct imx_media_dev *dev);
+int imx_media_csc_scaler_device_register(struct imx_media_video_dev *vdev);
+void imx_media_csc_scaler_device_unregister(struct imx_media_video_dev *vdev);
+
 /* subdev group ids */
 #define IMX_MEDIA_GRP_ID_CSI2          BIT(8)
 #define IMX_MEDIA_GRP_ID_CSI           BIT(9)