| /* |
| * 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 <linux/types.h> |
| #include <linux/device.h> |
| #include <linux/mod_devicetable.h> |
| #include <linux/kref.h> |
| #include <linux/mutex.h> |
| |
| /* 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; |
| |
| /** |
| * rpmsg_channel - devices that belong to the rpmsg bus are called channels |
| * @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_channel { |
| struct virtproc_info *vrp; |
| struct device dev; |
| struct rpmsg_device_id id; |
| u32 src; |
| u32 dst; |
| struct rpmsg_endpoint *ept; |
| bool announce; |
| }; |
| |
| typedef void (*rpmsg_rx_cb_t)(struct rpmsg_channel *, 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_channel *rpdev; |
| struct kref refcount; |
| rpmsg_rx_cb_t cb; |
| struct mutex cb_lock; |
| u32 addr; |
| void *priv; |
| }; |
| |
| /** |
| * 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_channel *dev); |
| void (*remove)(struct rpmsg_channel *dev); |
| void (*callback)(struct rpmsg_channel *, void *, int, void *, u32); |
| }; |
| |
| int register_rpmsg_device(struct rpmsg_channel *dev); |
| void unregister_rpmsg_device(struct rpmsg_channel *dev); |
| int register_rpmsg_driver(struct rpmsg_driver *drv); |
| void unregister_rpmsg_driver(struct rpmsg_driver *drv); |
| void rpmsg_destroy_ept(struct rpmsg_endpoint *); |
| struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_channel *, |
| rpmsg_rx_cb_t cb, void *priv, u32 addr); |
| int |
| rpmsg_send_offchannel_raw(struct rpmsg_channel *, u32, u32, void *, int, bool); |
| |
| /** |
| * rpmsg_send() - send a message across to the remote processor |
| * @rpdev: the rpmsg channel |
| * @data: payload of message |
| * @len: length of payload |
| * |
| * This function sends @data of length @len on the @rpdev channel. |
| * The message will be sent to the remote processor which the @rpdev |
| * channel belongs to, using @rpdev's source and destination addresses. |
| * In case there are no TX buffers available, the function will block until |
| * one becomes available, or a timeout of 15 seconds elapses. When the latter |
| * happens, -ERESTARTSYS is returned. |
| * |
| * Can only be called from process context (for now). |
| * |
| * Returns 0 on success and an appropriate error value on failure. |
| */ |
| static inline int rpmsg_send(struct rpmsg_channel *rpdev, void *data, int len) |
| { |
| u32 src = rpdev->src, dst = rpdev->dst; |
| |
| return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); |
| } |
| |
| /** |
| * rpmsg_sendto() - send a message across to the remote processor, specify dst |
| * @rpdev: the rpmsg channel |
| * @data: payload of message |
| * @len: length of payload |
| * @dst: destination address |
| * |
| * This function sends @data of length @len to the remote @dst address. |
| * The message will be sent to the remote processor which the @rpdev |
| * channel belongs to, using @rpdev's source address. |
| * In case there are no TX buffers available, the function will block until |
| * one becomes available, or a timeout of 15 seconds elapses. When the latter |
| * happens, -ERESTARTSYS is returned. |
| * |
| * Can only be called from process context (for now). |
| * |
| * Returns 0 on success and an appropriate error value on failure. |
| */ |
| static inline |
| int rpmsg_sendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst) |
| { |
| u32 src = rpdev->src; |
| |
| return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); |
| } |
| |
| /** |
| * rpmsg_send_offchannel() - send a message using explicit src/dst addresses |
| * @rpdev: the rpmsg channel |
| * @src: source address |
| * @dst: destination address |
| * @data: payload of message |
| * @len: length of payload |
| * |
| * This function sends @data of length @len to the remote @dst address, |
| * and uses @src as the source address. |
| * The message will be sent to the remote processor which the @rpdev |
| * channel belongs to. |
| * In case there are no TX buffers available, the function will block until |
| * one becomes available, or a timeout of 15 seconds elapses. When the latter |
| * happens, -ERESTARTSYS is returned. |
| * |
| * Can only be called from process context (for now). |
| * |
| * Returns 0 on success and an appropriate error value on failure. |
| */ |
| static inline |
| int rpmsg_send_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, |
| void *data, int len) |
| { |
| return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); |
| } |
| |
| /** |
| * rpmsg_send() - send a message across to the remote processor |
| * @rpdev: the rpmsg channel |
| * @data: payload of message |
| * @len: length of payload |
| * |
| * This function sends @data of length @len on the @rpdev channel. |
| * The message will be sent to the remote processor which the @rpdev |
| * channel belongs to, using @rpdev's source and destination addresses. |
| * In case there are no TX buffers available, the function will immediately |
| * return -ENOMEM without waiting until one becomes available. |
| * |
| * Can only be called from process context (for now). |
| * |
| * Returns 0 on success and an appropriate error value on failure. |
| */ |
| static inline |
| int rpmsg_trysend(struct rpmsg_channel *rpdev, void *data, int len) |
| { |
| u32 src = rpdev->src, dst = rpdev->dst; |
| |
| return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); |
| } |
| |
| /** |
| * rpmsg_sendto() - send a message across to the remote processor, specify dst |
| * @rpdev: the rpmsg channel |
| * @data: payload of message |
| * @len: length of payload |
| * @dst: destination address |
| * |
| * This function sends @data of length @len to the remote @dst address. |
| * The message will be sent to the remote processor which the @rpdev |
| * channel belongs to, using @rpdev's source address. |
| * In case there are no TX buffers available, the function will immediately |
| * return -ENOMEM without waiting until one becomes available. |
| * |
| * Can only be called from process context (for now). |
| * |
| * Returns 0 on success and an appropriate error value on failure. |
| */ |
| static inline |
| int rpmsg_trysendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst) |
| { |
| u32 src = rpdev->src; |
| |
| return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); |
| } |
| |
| /** |
| * rpmsg_send_offchannel() - send a message using explicit src/dst addresses |
| * @rpdev: the rpmsg channel |
| * @src: source address |
| * @dst: destination address |
| * @data: payload of message |
| * @len: length of payload |
| * |
| * This function sends @data of length @len to the remote @dst address, |
| * and uses @src as the source address. |
| * The message will be sent to the remote processor which the @rpdev |
| * channel belongs to. |
| * In case there are no TX buffers available, the function will immediately |
| * return -ENOMEM without waiting until one becomes available. |
| * |
| * Can only be called from process context (for now). |
| * |
| * Returns 0 on success and an appropriate error value on failure. |
| */ |
| static inline |
| int rpmsg_trysend_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, |
| void *data, int len) |
| { |
| return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); |
| } |
| |
| #endif /* _LINUX_RPMSG_H */ |