@@ -331,6 +331,25 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
EXPORT_SYMBOL(rpmsg_trysend_offchannel);
/**
+ * rpmsg_set_flow_control() - sets/clears serial flow control signals
+ * @ept: the rpmsg endpoint
+ * @enable: pause/resume incoming data flow
+ * @dst: destination address of the endpoint
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable, u32 dst)
+{
+ if (WARN_ON(!ept))
+ return -EINVAL;
+ if (!ept->ops->set_flow_control)
+ return -ENXIO;
+
+ return ept->ops->set_flow_control(ept, enable, dst);
+}
+EXPORT_SYMBOL(rpmsg_set_flow_control);
+
+/**
* rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
* @ept: the rpmsg endpoint
*
@@ -539,6 +558,8 @@ static int rpmsg_dev_probe(struct device *dev)
rpdev->ept = ept;
rpdev->src = ept->addr;
+
+ ept->flow_cb = rpdrv->flowcontrol;
}
err = rpdrv->probe(rpdev);
@@ -55,6 +55,7 @@ struct rpmsg_device_ops {
* @trysendto: see @rpmsg_trysendto(), optional
* @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional
* @poll: see @rpmsg_poll(), optional
+ * @set_flow_control: see @rpmsg_set_flow_control(), optional
* @get_mtu: see @rpmsg_get_mtu(), optional
*
* Indirection table for the operations that a rpmsg backend should implement.
@@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops {
void *data, int len);
__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
poll_table *wait);
+ int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable, u32 dst);
ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
};
@@ -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 status 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 enable, 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 enable, 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 */