Instantiate the rpmsg_char device on virtio RPMsg bus creation. This provides the capability, with the RPMSG_CREATE_EPT_IOCTL ioctl, to create RPMsg char device endpoints relying on the rpmsg_chrdev_create_eptdev API. Notice that the created endpoints are attached to the rpmsg_ctldev device, but not associated to a channel. As consequence, the endpoint source and destination addresses have to been specified and there is no channel creation and no name service announcement to inform the remote side. Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx> --- update vs [1] - rework the changelog - remove useless rpdev_ns pointer initialisation. [1]: https://patchwork.kernel.org/project/linux-remoteproc/patch/20210219111501.14261-12-arnaud.pouliquen@xxxxxxxxxxx/ --- drivers/rpmsg/virtio_rpmsg_bus.c | 62 +++++++++++++++++++++++++++++--- 1 file changed, 57 insertions(+), 5 deletions(-) diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index e87d4cf926eb..8e49a3bacfc7 100644 --- a/drivers/rpmsg/virtio_rpmsg_bus.c +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -813,14 +813,57 @@ static void rpmsg_xmit_done(struct virtqueue *svq) wake_up_interruptible(&vrp->sendq); } +/* + * Called to expose to user a /dev/rpmsg_ctrlX interface allowing to + * create endpoint-to-endpoint communication without associated RPMsg channel. + * The endpoints are rattached to the ctrldev RPMsg device. + */ +static struct rpmsg_device *rpmsg_virtio_add_ctrl_dev(struct virtio_device *vdev) +{ + struct virtproc_info *vrp = vdev->priv; + struct virtio_rpmsg_channel *vch; + struct rpmsg_device *rpdev_ctrl; + int err = 0; + + vch = kzalloc(sizeof(*vch), GFP_KERNEL); + if (!vch) + return ERR_PTR(-ENOMEM); + + /* Link the channel to the vrp */ + vch->vrp = vrp; + + /* Assign public information to the rpmsg_device */ + rpdev_ctrl = &vch->rpdev; + rpdev_ctrl->ops = &virtio_rpmsg_ops; + + rpdev_ctrl->dev.parent = &vrp->vdev->dev; + rpdev_ctrl->dev.release = virtio_rpmsg_release_device; + rpdev_ctrl->little_endian = virtio_is_little_endian(vrp->vdev); + + err = rpmsg_chrdev_register_device(rpdev_ctrl); + if (err) { + kfree(vch); + return ERR_PTR(err); + } + + return rpdev_ctrl; +} + +static void rpmsg_virtio_del_ctrl_dev(struct rpmsg_device *rpdev_ctrl) +{ + if (!rpdev_ctrl) + return; + kfree(to_virtio_rpmsg_channel(rpdev_ctrl)); +} + static int rpmsg_probe(struct virtio_device *vdev) { vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done }; static const char * const names[] = { "input", "output" }; struct virtqueue *vqs[2]; struct virtproc_info *vrp; - struct virtio_rpmsg_channel *vch; - struct rpmsg_device *rpdev_ns; + struct virtio_rpmsg_channel *vch = NULL; + struct rpmsg_device *rpdev_ns, *rpdev_ctrl; void *bufs_va; int err = 0, i; size_t total_buf_space; @@ -894,12 +937,18 @@ static int rpmsg_probe(struct virtio_device *vdev) vdev->priv = vrp; + rpdev_ctrl = rpmsg_virtio_add_ctrl_dev(vdev); + if (IS_ERR(rpdev_ctrl)) { + err = PTR_ERR(rpdev_ctrl); + goto free_coherent; + } + /* if supported by the remote processor, enable the name service */ if (virtio_has_feature(vdev, VIRTIO_RPMSG_F_NS)) { vch = kzalloc(sizeof(*vch), GFP_KERNEL); if (!vch) { err = -ENOMEM; - goto free_coherent; + goto free_ctrldev; } /* Link the channel to our vrp */ @@ -915,7 +964,7 @@ static int rpmsg_probe(struct virtio_device *vdev) err = rpmsg_ns_register_device(rpdev_ns); if (err) - goto free_coherent; + goto free_vch; } /* @@ -939,8 +988,11 @@ static int rpmsg_probe(struct virtio_device *vdev) return 0; -free_coherent: +free_vch: kfree(vch); +free_ctrldev: + rpmsg_virtio_del_ctrl_dev(rpdev_ctrl); +free_coherent: dma_free_coherent(vdev->dev.parent, total_buf_space, bufs_va, vrp->bufs_dma); vqs_del: -- 2.17.1
