video: camera: Port RTCPU drivers to OOT tree

Port RTCPU drivers from kernel/nvidia to kernel/nvidia-oot.
In addition to copying the files this patch:
1) Modifies make files to build rtcpu drivers as modules
2) Modifies licenses of all ported files to SPDX
3) Adds MODULE_LICENSE macro to all modules
4) Removes checks for old kernel versions and the dead code after those checks
5) Fixes style errors according to checkpatch.pl

Change-Id: If64296a22ce958e5326c7509cb69f8f7154f598e
Signed-off-by: Frank Chen <frankc@nvidia.com>
Signed-off-by: Matti Ryttylainen <mryttylainen@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/2783040
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Ankur Pawar <ankurp@nvidia.com>
Reviewed-by: Semi Malinen <smalinen@nvidia.com>
Reviewed-by: Pekka Pessi <ppessi@nvidia.com>
GVS: Gerrit_Virtual_Submit <buildbot_gerritrpt@nvidia.com>

include/linux/tegra-ivc-bus.h

@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ */
+
+#ifndef _LINUX_TEGRA_IVC_BUS_H
+#define _LINUX_TEGRA_IVC_BUS_H
+
+#include <linux/tegra-ivc-instance.h>
+#include <linux/types.h>
+
+extern struct bus_type tegra_ivc_bus_type;
+extern struct device_type tegra_ivc_bus_dev_type;
+struct tegra_ivc_bus;
+struct tegra_ivc_rpc_data;
+
+struct tegra_ivc_bus *tegra_ivc_bus_create(struct device *);
+
+void tegra_ivc_bus_ready(struct tegra_ivc_bus *bus, bool online);
+void tegra_ivc_bus_destroy(struct tegra_ivc_bus *bus);
+int tegra_ivc_bus_boot_sync(struct tegra_ivc_bus *bus);
+void tegra_ivc_bus_notify(struct tegra_ivc_bus *bus, u16 group);
+
+struct tegra_ivc_driver {
+	struct device_driver driver;
+	struct device_type *dev_type;
+	union {
+		const struct tegra_ivc_channel_ops *channel;
+	} ops;
+};
+
+static inline struct tegra_ivc_driver *to_tegra_ivc_driver(
+						struct device_driver *drv)
+{
+	if (drv == NULL)
+		return NULL;
+	return container_of(drv, struct tegra_ivc_driver, driver);
+}
+
+int tegra_ivc_driver_register(struct tegra_ivc_driver *drv);
+void tegra_ivc_driver_unregister(struct tegra_ivc_driver *drv);
+#define tegra_ivc_module_driver(drv) \
+	module_driver(drv, tegra_ivc_driver_register, \
+			tegra_ivc_driver_unregister)
+
+#define tegra_ivc_subsys_driver(__driver, __register, __unregister, ...) \
+static int __init __driver##_init(void) \
+{ \
+	return __register(&(__driver), ##__VA_ARGS__); \
+} \
+subsys_initcall_sync(__driver##_init);
+
+#define tegra_ivc_subsys_driver_default(__driver) \
+tegra_ivc_subsys_driver(__driver, \
+						tegra_ivc_driver_register, \
+						tegra_ivc_driver_unregister)
+
+/* IVC channel driver support */
+extern struct device_type tegra_ivc_channel_type;
+
+struct tegra_ivc_channel {
+	struct ivc ivc;
+	struct device dev;
+	const struct tegra_ivc_channel_ops __rcu *ops;
+	struct tegra_ivc_channel *next;
+	struct mutex ivc_wr_lock;
+	struct tegra_ivc_rpc_data *rpc_priv;
+	atomic_t bus_resets;
+	u16 group;
+	bool is_ready;
+};
+
+static inline bool tegra_ivc_channel_online_check(
+		struct tegra_ivc_channel *chan)
+{
+	atomic_set(&chan->bus_resets, 0);
+
+	smp_wmb();
+	smp_rmb();
+
+	return chan->is_ready;
+}
+
+static inline bool tegra_ivc_channel_has_been_reset(
+		struct tegra_ivc_channel *chan)
+{
+	smp_rmb();
+	return atomic_read(&chan->bus_resets) != 0;
+}
+
+static inline void *tegra_ivc_channel_get_drvdata(
+		struct tegra_ivc_channel *chan)
+{
+	return dev_get_drvdata(&chan->dev);
+}
+
+static inline void tegra_ivc_channel_set_drvdata(
+		struct tegra_ivc_channel *chan, void *data)
+{
+	dev_set_drvdata(&chan->dev, data);
+}
+
+static inline struct tegra_ivc_channel *to_tegra_ivc_channel(
+		struct device *dev)
+{
+	return container_of(dev, struct tegra_ivc_channel, dev);
+}
+
+static inline struct device *tegra_ivc_channel_to_camrtc_dev(
+	struct tegra_ivc_channel *ch)
+{
+	if (unlikely(ch == NULL))
+		return NULL;
+
+	BUG_ON(ch->dev.parent == NULL);
+	BUG_ON(ch->dev.parent->parent == NULL);
+
+	return ch->dev.parent->parent;
+}
+
+int tegra_ivc_channel_runtime_get(struct tegra_ivc_channel *chan);
+void tegra_ivc_channel_runtime_put(struct tegra_ivc_channel *chan);
+
+struct tegra_ivc_channel_ops {
+	int (*probe)(struct tegra_ivc_channel *);
+	void (*ready)(struct tegra_ivc_channel *, bool online);
+	void (*remove)(struct tegra_ivc_channel *);
+	void (*notify)(struct tegra_ivc_channel *);
+};
+
+/* Legacy mailbox support */
+struct tegra_ivc_mbox_msg {
+	int length;
+	void *data;
+};
+
+#endif