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Diffstat (limited to 'include/linux/rpmsg.h')
-rw-r--r-- | include/linux/rpmsg.h | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h new file mode 100644 index 000000000..523c98b96 --- /dev/null +++ b/include/linux/rpmsg.h @@ -0,0 +1,337 @@ +/* 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); + +/** + * 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_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); + int (*callback)(struct rpmsg_device *, void *, int, void *, u32); +}; + +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); + +#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; +} + +#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 */ |