From 8ce49c2a2aa53afde9a20a8ce02b069d3b262af0 Mon Sep 17 00:00:00 2001 From: Deepak Kumar Singh Date: Fri, 7 Jul 2023 03:11:36 +0530 Subject: rpmsg: core: Add signal API support Some transports like Glink support the state notifications between clients using flow control signals similar to serial protocol signals. Local glink client drivers can send and receive flow control status to glink clients running on remote processors. Add APIs to support sending and receiving of flow control status by rpmsg clients. Signed-off-by: Deepak Kumar Singh Signed-off-by: Sarannya S Acked-by: Arnaud Pouliquen Link: https://lore.kernel.org/r/1688679698-31274-2-git-send-email-quic_sarannya@quicinc.com Signed-off-by: Bjorn Andersson --- include/linux/rpmsg.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/linux') diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 523c98b96cb4..90d8e4475f80 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -64,12 +64,14 @@ struct rpmsg_device { }; 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 @@ -92,6 +94,7 @@ 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; @@ -106,6 +109,7 @@ struct rpmsg_endpoint { * @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; @@ -113,6 +117,7 @@ struct rpmsg_driver { 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) @@ -192,6 +197,8 @@ __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, 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, @@ -316,6 +323,14 @@ static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) 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 */ -- cgit v1.2.3