1 files changed, 352 insertions, 0 deletions
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
new file mode 100644
index 000000000..90d8e4475
--- /dev/null
+++ b/include/linux/rpmsg.h
@@ -0,0 +1,352 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * Remote processor messaging
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ * All rights reserved.
+ */
+
+#ifndef _LINUX_RPMSG_H
+#define _LINUX_RPMSG_H
+
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/mod_devicetable.h>
+#include <linux/kref.h>
+#include <linux/mutex.h>
+#include <linux/poll.h>
+#include <linux/rpmsg/byteorder.h>
+#include <uapi/linux/rpmsg.h>
+
+struct rpmsg_device;
+struct rpmsg_endpoint;
+struct rpmsg_device_ops;
+struct rpmsg_endpoint_ops;
+
+/**
+ * struct rpmsg_channel_info - channel info representation
+ * @name: name of service
+ * @src: local address
+ * @dst: destination address
+ */
+struct rpmsg_channel_info {
+	char name[RPMSG_NAME_SIZE];
+	u32 src;
+	u32 dst;
+};
+
+/**
+ * rpmsg_device - device that belong to the rpmsg bus
+ * @dev: the device struct
+ * @id: device id (used to match between rpmsg drivers and devices)
+ * @driver_override: driver name to force a match; do not set directly,
+ *                   because core frees it; use driver_set_override() to
+ *                   set or clear it.
+ * @src: local address
+ * @dst: destination address
+ * @ept: the rpmsg endpoint of this channel
+ * @announce: if set, rpmsg will announce the creation/removal of this channel
+ * @little_endian: True if transport is using little endian byte representation
+ */
+struct rpmsg_device {
+	struct device dev;
+	struct rpmsg_device_id id;
+	const char *driver_override;
+	u32 src;
+	u32 dst;
+	struct rpmsg_endpoint *ept;
+	bool announce;
+	bool little_endian;
+
+	const struct rpmsg_device_ops *ops;
+};
+
+typedef int (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32);
+typedef int (*rpmsg_flowcontrol_cb_t)(struct rpmsg_device *, void *, bool);
+
+/**
+ * struct rpmsg_endpoint - binds a local rpmsg address to its user
+ * @rpdev: rpmsg channel device
+ * @refcount: when this drops to zero, the ept is deallocated
+ * @cb: rx callback handler
+ * @flow_cb: remote flow control callback handler
+ * @cb_lock: must be taken before accessing/changing @cb
+ * @addr: local rpmsg address
+ * @priv: private data for the driver's use
+ *
+ * In essence, an rpmsg endpoint represents a listener on the rpmsg bus, as
+ * it binds an rpmsg address with an rx callback handler.
+ *
+ * Simple rpmsg drivers shouldn't use this struct directly, because
+ * things just work: every rpmsg driver provides an rx callback upon
+ * registering to the bus, and that callback is then bound to its rpmsg
+ * address when the driver is probed. When relevant inbound messages arrive
+ * (i.e. messages which their dst address equals to the src address of
+ * the rpmsg channel), the driver's handler is invoked to process it.
+ *
+ * More complicated drivers though, that do need to allocate additional rpmsg
+ * addresses, and bind them to different rx callbacks, must explicitly
+ * create additional endpoints by themselves (see rpmsg_create_ept()).
+ */
+struct rpmsg_endpoint {
+	struct rpmsg_device *rpdev;
+	struct kref refcount;
+	rpmsg_rx_cb_t cb;
+	rpmsg_flowcontrol_cb_t flow_cb;
+	struct mutex cb_lock;
+	u32 addr;
+	void *priv;
+
+	const struct rpmsg_endpoint_ops *ops;
+};
+
+/**
+ * struct rpmsg_driver - rpmsg driver struct
+ * @drv: underlying device driver
+ * @id_table: rpmsg ids serviced by this driver
+ * @probe: invoked when a matching rpmsg channel (i.e. device) is found
+ * @remove: invoked when the rpmsg channel is removed
+ * @callback: invoked when an inbound message is received on the channel
+ * @flowcontrol: invoked when remote side flow control request is received
+ */
+struct rpmsg_driver {
+	struct device_driver drv;
+	const struct rpmsg_device_id *id_table;
+	int (*probe)(struct rpmsg_device *dev);
+	void (*remove)(struct rpmsg_device *dev);
+	int (*callback)(struct rpmsg_device *, void *, int, void *, u32);
+	int (*flowcontrol)(struct rpmsg_device *, void *, bool);
+};
+
+static inline u16 rpmsg16_to_cpu(struct rpmsg_device *rpdev, __rpmsg16 val)
+{
+	if (!rpdev)
+		return __rpmsg16_to_cpu(rpmsg_is_little_endian(), val);
+	else
+		return __rpmsg16_to_cpu(rpdev->little_endian, val);
+}
+
+static inline __rpmsg16 cpu_to_rpmsg16(struct rpmsg_device *rpdev, u16 val)
+{
+	if (!rpdev)
+		return __cpu_to_rpmsg16(rpmsg_is_little_endian(), val);
+	else
+		return __cpu_to_rpmsg16(rpdev->little_endian, val);
+}
+
+static inline u32 rpmsg32_to_cpu(struct rpmsg_device *rpdev, __rpmsg32 val)
+{
+	if (!rpdev)
+		return __rpmsg32_to_cpu(rpmsg_is_little_endian(), val);
+	else
+		return __rpmsg32_to_cpu(rpdev->little_endian, val);
+}
+
+static inline __rpmsg32 cpu_to_rpmsg32(struct rpmsg_device *rpdev, u32 val)
+{
+	if (!rpdev)
+		return __cpu_to_rpmsg32(rpmsg_is_little_endian(), val);
+	else
+		return __cpu_to_rpmsg32(rpdev->little_endian, val);
+}
+
+static inline u64 rpmsg64_to_cpu(struct rpmsg_device *rpdev, __rpmsg64 val)
+{
+	if (!rpdev)
+		return __rpmsg64_to_cpu(rpmsg_is_little_endian(), val);
+	else
+		return __rpmsg64_to_cpu(rpdev->little_endian, val);
+}
+
+static inline __rpmsg64 cpu_to_rpmsg64(struct rpmsg_device *rpdev, u64 val)
+{
+	if (!rpdev)
+		return __cpu_to_rpmsg64(rpmsg_is_little_endian(), val);
+	else
+		return __cpu_to_rpmsg64(rpdev->little_endian, val);
+}
+
+#if IS_ENABLED(CONFIG_RPMSG)
+
+int rpmsg_register_device_override(struct rpmsg_device *rpdev,
+				   const char *driver_override);
+int rpmsg_register_device(struct rpmsg_device *rpdev);
+int rpmsg_unregister_device(struct device *parent,
+			    struct rpmsg_channel_info *chinfo);
+int __register_rpmsg_driver(struct rpmsg_driver *drv, struct module *owner);
+void unregister_rpmsg_driver(struct rpmsg_driver *drv);
+void rpmsg_destroy_ept(struct rpmsg_endpoint *);
+struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *,
+					rpmsg_rx_cb_t cb, void *priv,
+					struct rpmsg_channel_info chinfo);
+
+int rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len);
+int rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst);
+int rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
+			  void *data, int len);
+
+int rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len);
+int rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst);
+int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
+			     void *data, int len);
+
+__poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
+			poll_table *wait);
+
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
+
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst);
+
+#else
+
+static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev,
+						 const char *driver_override)
+{
+	return -ENXIO;
+}
+
+static inline int rpmsg_register_device(struct rpmsg_device *rpdev)
+{
+	return -ENXIO;
+}
+
+static inline int rpmsg_unregister_device(struct device *parent,
+					  struct rpmsg_channel_info *chinfo)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline int __register_rpmsg_driver(struct rpmsg_driver *drv,
+					  struct module *owner)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline void unregister_rpmsg_driver(struct rpmsg_driver *drv)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+}
+
+static inline void rpmsg_destroy_ept(struct rpmsg_endpoint *ept)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+}
+
+static inline struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *rpdev,
+						      rpmsg_rx_cb_t cb,
+						      void *priv,
+						      struct rpmsg_channel_info chinfo)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return NULL;
+}
+
+static inline int rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline int rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len,
+			       u32 dst)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+
+}
+
+static inline int rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src,
+					u32 dst, void *data, int len)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline int rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline int rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
+				  int len, u32 dst)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
+					   u32 dst, void *data, int len)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
+				      struct file *filp, poll_table *wait)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return 0;
+}
+
+static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+#endif /* IS_ENABLED(CONFIG_RPMSG) */
+
+/* use a macro to avoid include chaining to get THIS_MODULE */
+#define register_rpmsg_driver(drv) \
+	__register_rpmsg_driver(drv, THIS_MODULE)
+
+/**
+ * module_rpmsg_driver() - Helper macro for registering an rpmsg driver
+ * @__rpmsg_driver: rpmsg_driver struct
+ *
+ * Helper macro for rpmsg drivers which do not do anything special in module
+ * init/exit. This eliminates a lot of boilerplate.  Each module may only
+ * use this macro once, and calling it replaces module_init() and module_exit()
+ */
+#define module_rpmsg_driver(__rpmsg_driver) \
+	module_driver(__rpmsg_driver, register_rpmsg_driver, \
+			unregister_rpmsg_driver)
+
+#endif /* _LINUX_RPMSG_H */