Commit c486682a authored by Arnaud Pouliquen's avatar Arnaud Pouliquen Committed by Bjorn Andersson
Browse files

rpmsg: virtio: Register the rpmsg_char device 



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.

Reviewed-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: default avatarArnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20210311140413.31725-6-arnaud.pouliquen@foss.st.com


Signed-off-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
parent b4ce7e2e

drivers/rpmsg/virtio_rpmsg_bus.c

+57 −5
Original line number Diff line number Diff line
@@ -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: