media: mtk-vcodec: vdec: add media device if using stateless api

The stateless API requires a media device for issuing requests. Add one
if we are being instantiated as a stateless decoder.

[acourbot: refactor, cleanup and split]
[tzungbi: fix wrong device minor number reference]
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Co-developed-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/Kconfig

@@ -315,6 +315,8 @@ config VIDEO_MEDIATEK_VCODEC
 	select VIDEO_MEDIATEK_VCODEC_VPU if VIDEO_MEDIATEK_VPU
 	select VIDEO_MEDIATEK_VCODEC_SCP if MTK_SCP
 	select V4L2_H264
+	select MEDIA_CONTROLLER
+	select MEDIA_CONTROLLER_REQUEST_API
 	help
 	  Mediatek video codec driver provides HW capability to
 	  encode and decode in a range of video formats on MT8173

drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c

@@ -14,6 +14,7 @@
 #include <media/v4l2-event.h>
 #include <media/v4l2-mem2mem.h>
 #include <media/videobuf2-dma-contig.h>
+#include <media/v4l2-device.h>
 
 #include "mtk_vcodec_drv.h"
 #include "mtk_vcodec_dec.h"
@@ -316,18 +317,47 @@ static int mtk_vcodec_probe(struct platform_device *pdev)
 		goto err_event_workq;
 	}
 
+	if (dev->vdec_pdata->uses_stateless_api) {
+		dev->mdev_dec.dev = &pdev->dev;
+		strscpy(dev->mdev_dec.model, MTK_VCODEC_DEC_NAME,
+			sizeof(dev->mdev_dec.model));
+
+		media_device_init(&dev->mdev_dec);
+		dev->mdev_dec.ops = &mtk_vcodec_media_ops;
+		dev->v4l2_dev.mdev = &dev->mdev_dec;
+
+		ret = v4l2_m2m_register_media_controller(dev->m2m_dev_dec, dev->vfd_dec,
+							 MEDIA_ENT_F_PROC_VIDEO_DECODER);
+		if (ret) {
+			mtk_v4l2_err("Failed to register media controller");
+			goto err_reg_cont;
+		}
+
+		ret = media_device_register(&dev->mdev_dec);
+		if (ret) {
+			mtk_v4l2_err("Failed to register media device");
+			goto err_media_reg;
+		}
+
+		mtk_v4l2_debug(0, "media registered as /dev/media%d", vfd_dec->minor);
+	}
 	ret = video_register_device(vfd_dec, VFL_TYPE_VIDEO, 0);
 	if (ret) {
 		mtk_v4l2_err("Failed to register video device");
 		goto err_dec_reg;
 	}
 
-	mtk_v4l2_debug(0, "decoder registered as /dev/video%d",
-		vfd_dec->num);
+	mtk_v4l2_debug(0, "decoder registered as /dev/video%d", vfd_dec->minor);
 
 	return 0;
 
 err_dec_reg:
+	if (dev->vdec_pdata->uses_stateless_api)
+		media_device_unregister(&dev->mdev_dec);
+err_media_reg:
+	if (dev->vdec_pdata->uses_stateless_api)
+		v4l2_m2m_unregister_media_controller(dev->m2m_dev_dec);
+err_reg_cont:
 	destroy_workqueue(dev->decode_workqueue);
 err_event_workq:
 	v4l2_m2m_release(dev->m2m_dev_dec);
@@ -360,6 +390,13 @@ static int mtk_vcodec_dec_remove(struct platform_device *pdev)
 
 	flush_workqueue(dev->decode_workqueue);
 	destroy_workqueue(dev->decode_workqueue);
+
+	if (media_devnode_is_registered(dev->mdev_dec.devnode)) {
+		media_device_unregister(&dev->mdev_dec);
+		v4l2_m2m_unregister_media_controller(dev->m2m_dev_dec);
+		media_device_cleanup(&dev->mdev_dec);
+	}
+
 	if (dev->m2m_dev_dec)
 		v4l2_m2m_release(dev->m2m_dev_dec);
 

drivers/media/platform/mtk-vcodec/mtk_vcodec_drv.h

@@ -390,6 +390,7 @@ struct mtk_vcodec_enc_pdata {
  * struct mtk_vcodec_dev - driver data
  * @v4l2_dev: V4L2 device to register video devices for.
  * @vfd_dec: Video device for decoder
+ * @mdev_dec: Media device for decoder
  * @vfd_enc: Video device for encoder.
  *
  * @m2m_dev_dec: m2m device for decoder
@@ -427,6 +428,7 @@ struct mtk_vcodec_enc_pdata {
 struct mtk_vcodec_dev {
 	struct v4l2_device v4l2_dev;
 	struct video_device *vfd_dec;
+	struct media_device mdev_dec;
 	struct video_device *vfd_enc;
 
 	struct v4l2_m2m_dev *m2m_dev_dec;