Add the capability for a rpmsg local endpoint to receive information
of a remote endpoint state using the flow control channel.
The virtio_rpmsg_remote_flowctrl function calls the endpoint which
matches with the chinfo.
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
---
drivers/rpmsg/virtio_rpmsg_bus.c | 38 ++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 0db8043e6c49..785fda77984e 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -305,6 +305,7 @@ __rpmsg_destroy_ept(struct virtproc_info *vrp, struct rpmsg_endpoint *ept)
/* make sure in-flight inbound messages won't invoke cb anymore */
mutex_lock(&ept->cb_lock);
ept->cb = NULL;
+ ept->sig_cb = NULL;
mutex_unlock(&ept->cb_lock);
kref_put(&ept->refcount, __ept_release);
@@ -365,12 +366,49 @@ static int virtio_rpmsg_announce_destroy(struct rpmsg_device *rpdev)
return err;
}
+static int virtio_rpmsg_remote_flowctrl(struct rpmsg_device *rpdev,
+ struct rpmsg_channel_info *chinfo,
+ bool enable)
+{
+ struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
+ struct virtproc_info *vrp = vch->vrp;
+ struct rpmsg_endpoint *ept;
+
+ /* Use the dst addr to fetch the callback of the appropriate user */
+ mutex_lock(&vrp->endpoints_lock);
+
+ ept = idr_find(&vrp->endpoints, chinfo->dst);
+
+ /* Let's make sure no one deallocates ept while we use it */
+ if (ept)
+ kref_get(&ept->refcount);
+
+ mutex_unlock(&vrp->endpoints_lock);
+
+ if (!ept)
+ return -EINVAL;
+
+ /* Make sure ept->sig_cb doesn't go away while we use it */
+ mutex_lock(&ept->cb_lock);
+
+ if (ept->sig_cb)
+ ept->sig_cb(ept->rpdev, ept->priv, enable);
+
+ mutex_unlock(&ept->cb_lock);
+
+ /* Farewell, ept, we don't need you anymore */
+ kref_put(&ept->refcount, __ept_release);
+
+ return 0;
+}
+
static const struct rpmsg_device_ops virtio_rpmsg_ops = {
.create_channel = virtio_rpmsg_create_channel,
.release_channel = virtio_rpmsg_release_channel,
.create_ept = virtio_rpmsg_create_ept,
.announce_create = virtio_rpmsg_announce_create,
.announce_destroy = virtio_rpmsg_announce_destroy,
+ .announce_remote_fc = virtio_rpmsg_remote_flowctrl,
};
static void virtio_rpmsg_release_device(struct device *dev)
--
2.25.1
