media: ti-vpe: cal: Implement media controller centric API

The CAL driver is video node centric, it controls the whole device
through the video device nodes. This limits the possible use cases as it
can't support sources that are more complex than a single subdev. To
support more complex hardware pipelines, implement support for the media
controller centric API. The exposed API can be selected through a module
parameter.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/Kconfig

@@ -186,6 +186,20 @@ config VIDEO_TI_CAL
 	  In TI Technical Reference Manual this module is referred as
 	  Camera Interface Subsystem (CAMSS).
 
+if VIDEO_TI_CAL
+
+config VIDEO_TI_CAL_MC
+	bool "Media Controller centric mode by default"
+	default n
+	help
+	  Enables Media Controller centric mode by default.
+
+	  If set, CAL driver will start in Media Controller mode by
+	  default. Note that this behavior can be overridden via
+	  module parameter 'mc_api'.
+
+endif # VIDEO_TI_CAL
+
 endif # V4L_PLATFORM_DRIVERS
 
 menuconfig V4L_MEM2MEM_DRIVERS

drivers/media/platform/ti-vpe/cal-camerarx.c

@@ -830,6 +830,7 @@ struct cal_camerarx *cal_camerarx_create(struct cal_dev *cal,
 	sd = &phy->subdev;
 	v4l2_subdev_init(sd, &cal_camerarx_subdev_ops);
 	sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+	sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
 	snprintf(sd->name, sizeof(sd->name), "CAMERARX%u", instance);
 	sd->dev = cal->dev;
 

drivers/media/platform/ti-vpe/cal.c

@@ -43,6 +43,16 @@ unsigned int cal_debug;
 module_param_named(debug, cal_debug, uint, 0644);
 MODULE_PARM_DESC(debug, "activates debug info");
 
+#ifdef CONFIG_VIDEO_TI_CAL_MC
+#define CAL_MC_API_DEFAULT 1
+#else
+#define CAL_MC_API_DEFAULT 0
+#endif
+
+bool cal_mc_api = CAL_MC_API_DEFAULT;
+module_param_named(mc_api, cal_mc_api, bool, 0444);
+MODULE_PARM_DESC(mc_api, "activates the MC API");
+
 /* ------------------------------------------------------------------
  *	Format Handling
  * ------------------------------------------------------------------
@@ -660,13 +670,17 @@ static int cal_async_notifier_complete(struct v4l2_async_notifier *notifier)
 {
 	struct cal_dev *cal = container_of(notifier, struct cal_dev, notifier);
 	unsigned int i;
+	int ret = 0;
 
 	for (i = 0; i < ARRAY_SIZE(cal->ctx); ++i) {
 		if (cal->ctx[i])
 			cal_ctx_v4l2_register(cal->ctx[i]);
 	}
 
-	return 0;
+	if (cal_mc_api)
+		ret = v4l2_device_register_subdev_nodes(&cal->v4l2_dev);
+
+	return ret;
 }
 
 static const struct v4l2_async_notifier_operations cal_async_notifier_ops = {

drivers/media/platform/ti-vpe/cal.h

@@ -160,6 +160,7 @@ struct cal_camerarx {
 	struct device_node	*sensor_ep_node;
 	struct device_node	*sensor_node;
 	struct v4l2_subdev	*sensor;
+	struct media_pipeline	pipe;
 
 	struct v4l2_subdev	subdev;
 	struct media_pad	pads[2];
@@ -224,6 +225,7 @@ struct cal_ctx {
 
 extern unsigned int cal_debug;
 extern int cal_video_nr;
+extern bool cal_mc_api;
 
 #define cal_dbg(level, cal, fmt, arg...)				\
 	do {								\