/* * Remote processor messaging * * Copyright (C) 2011 Texas Instruments, Inc. * Copyright (C) 2011 Google, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name Texas Instruments nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef _LINUX_RPMSG_H #define _LINUX_RPMSG_H #include #include #include #include #include /* The feature bitmap for virtio rpmsg */ #define VIRTIO_RPMSG_F_NS 0 /* RP supports name service notifications */ /** * struct rpmsg_hdr - common header for all rpmsg messages * @src: source address * @dst: destination address * @reserved: reserved for future use * @len: length of payload (in bytes) * @flags: message flags * @data: @len bytes of message payload data * * Every message sent(/received) on the rpmsg bus begins with this header. */ struct rpmsg_hdr { u32 src; u32 dst; u32 reserved; u16 len; u16 flags; u8 data[0]; } __packed; /** * struct rpmsg_ns_msg - dynamic name service announcement message * @name: name of remote service that is published * @addr: address of remote service that is published * @flags: indicates whether service is created or destroyed * * This message is sent across to publish a new service, or announce * about its removal. When we receive these messages, an appropriate * rpmsg channel (i.e device) is created/destroyed. In turn, the ->probe() * or ->remove() handler of the appropriate rpmsg driver will be invoked * (if/as-soon-as one is registered). */ struct rpmsg_ns_msg { char name[RPMSG_NAME_SIZE]; u32 addr; u32 flags; } __packed; /** * enum rpmsg_ns_flags - dynamic name service announcement flags * * @RPMSG_NS_CREATE: a new remote service was just created * @RPMSG_NS_DESTROY: a known remote service was just destroyed */ enum rpmsg_ns_flags { RPMSG_NS_CREATE = 0, RPMSG_NS_DESTROY = 1, }; #define RPMSG_ADDR_ANY 0xFFFFFFFF struct virtproc_info; 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 * @vrp: the remote processor this channel belongs to * @dev: the device struct * @id: device id (used to match between rpmsg drivers and devices) * @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 */ struct rpmsg_device { struct virtproc_info *vrp; struct device dev; struct rpmsg_device_id id; u32 src; u32 dst; struct rpmsg_endpoint *ept; bool announce; const struct rpmsg_device_ops *ops; }; typedef void (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32); /** * struct rpmsg_device_ops - indirection table for the rpmsg_device operations * @create_ept: create backend-specific endpoint, requried * @announce_create: announce presence of new channel, optional * @announce_destroy: announce destruction of channel, optional * * Indirection table for the operations that a rpmsg backend should implement. * @announce_create and @announce_destroy are optional as the backend might * advertise new channels implicitly by creating the endpoints. */ struct rpmsg_device_ops { struct rpmsg_endpoint *(*create_ept)(struct rpmsg_device *rpdev, rpmsg_rx_cb_t cb, void *priv, struct rpmsg_channel_info chinfo); int (*announce_create)(struct rpmsg_device *ept); int (*announce_destroy)(struct rpmsg_device *ept); }; /** * 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 * @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; struct mutex cb_lock; u32 addr; void *priv; const struct rpmsg_endpoint_ops *ops; }; /** * struct rpmsg_endpoint_ops - indirection table for rpmsg_endpoint operations * @destroy_ept: destroy the given endpoint, required * @send: see @rpmsg_send(), required * @sendto: see @rpmsg_sendto(), optional * @send_offchannel: see @rpmsg_send_offchannel(), optional * @trysend: see @rpmsg_trysend(), required * @trysendto: see @rpmsg_trysendto(), optional * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional * * Indirection table for the operations that a rpmsg backend should implement. * In addition to @destroy_ept, the backend must at least implement @send and * @trysend, while the variants sending data off-channel are optional. */ struct rpmsg_endpoint_ops { void (*destroy_ept)(struct rpmsg_endpoint *ept); int (*send)(struct rpmsg_endpoint *ept, void *data, int len); int (*sendto)(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); int (*send_offchannel)(struct rpmsg_endpoint *ept, u32 src, u32 dst, void *data, int len); int (*trysend)(struct rpmsg_endpoint *ept, void *data, int len); int (*trysendto)(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); int (*trysend_offchannel)(struct rpmsg_endpoint *ept, u32 src, u32 dst, void *data, int len); }; /** * 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 */ 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); void (*callback)(struct rpmsg_device *, void *, int, void *, u32); }; int register_rpmsg_device(struct rpmsg_device *dev); void unregister_rpmsg_device(struct rpmsg_device *dev); 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); /* 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) 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); #endif /* _LINUX_RPMSG_H */