Introduce the VIRTIO_RPMSG_F_FC feature in charge of the end
point flow control management.
The virtio feature is negotiated. If the remote side supports it,
the rpmsg_fc device is probed.
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
---
drivers/rpmsg/Kconfig | 1 +
drivers/rpmsg/virtio_rpmsg_bus.c | 32 +++++++++++++++++++++++++++++++-
2 files changed, 32 insertions(+), 1 deletion(-)
diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig
index c6659f27c617..e39cf32483de 100644
--- a/drivers/rpmsg/Kconfig
+++ b/drivers/rpmsg/Kconfig
@@ -89,6 +89,7 @@ config RPMSG_VIRTIO
depends on HAS_DMA
select RPMSG
select RPMSG_NS
+ select RPMSG_FC
select VIRTIO
endmenu
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 785fda77984e..40d2ab86b395 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -19,6 +19,7 @@
#include <linux/mutex.h>
#include <linux/rpmsg.h>
#include <linux/rpmsg/byteorder.h>
+#include <linux/rpmsg/fc.h>
#include <linux/rpmsg/ns.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
@@ -70,6 +71,7 @@ struct virtproc_info {
/* The feature bitmap for virtio rpmsg */
#define VIRTIO_RPMSG_F_NS 0 /* RP supports name service notifications */
+#define VIRTIO_RPMSG_F_FC 1 /* RP supports endpoint flow control notifications */
/**
* struct rpmsg_hdr - common header for all rpmsg messages
@@ -909,7 +911,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
struct virtqueue *vqs[2];
struct virtproc_info *vrp;
struct virtio_rpmsg_channel *vch = NULL;
- struct rpmsg_device *rpdev_ns, *rpdev_ctrl;
+ struct rpmsg_device *rpdev_ns = NULL, *rpdev_ctrl, *rpdev_fc;
void *bufs_va;
int err = 0, i;
size_t total_buf_space;
@@ -1013,6 +1015,30 @@ static int rpmsg_probe(struct virtio_device *vdev)
goto free_ctrldev;
}
+ /* If supported by the remote processor, enable the flow control service */
+ if (virtio_has_feature(vdev, VIRTIO_RPMSG_F_FC)) {
+ vch = kzalloc(sizeof(*vch), GFP_KERNEL);
+ if (!vch) {
+ err = -ENOMEM;
+ goto free_ns;
+ }
+
+ /* Link the channel to our vrp */
+ vch->vrp = vrp;
+
+ /* Assign public information to the rpmsg_device */
+ rpdev_fc = &vch->rpdev;
+ rpdev_fc->ops = &virtio_rpmsg_ops;
+ rpdev_fc->little_endian = virtio_is_little_endian(vrp->vdev);
+
+ rpdev_fc->dev.parent = &vrp->vdev->dev;
+ rpdev_fc->dev.release = virtio_rpmsg_release_device;
+
+ err = rpmsg_fc_register_device(rpdev_fc);
+ if (err)
+ goto free_ns;
+ }
+
/*
* Prepare to kick but don't notify yet - we can't do this before
* device is ready.
@@ -1034,6 +1060,9 @@ static int rpmsg_probe(struct virtio_device *vdev)
return 0;
+free_ns:
+ if (rpdev_ns)
+ device_unregister(&rpdev_ns->dev);
free_ctrldev:
rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
free_coherent:
@@ -1082,6 +1111,7 @@ static struct virtio_device_id id_table[] = {
static unsigned int features[] = {
VIRTIO_RPMSG_F_NS,
+ VIRTIO_RPMSG_F_FC,
};
static struct virtio_driver virtio_ipc_driver = {
--
2.25.1
