[PATCH v3 07/15] rpmsg: virtio: probe the rpmsg_ctrl device

From: Arnaud Pouliquen
Date: Thu Feb 04 2021 - 03:47:19 EST


Instantiate the rpmsg_ioctl device on virtio RPMsg bus creation.
This provides the possibility to expose the RPMSG_CREATE_EPT_IOCTL
to create RPMsg chdev endpoint.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>

---
V3:
Fix compilation issue
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

warnings:
drivers/rpmsg/virtio_rpmsg_bus.c:978 rpmsg_probe() error: uninitialized symbol 'vch'.
drivers/rpmsg/virtio_rpmsg_bus.c:979 rpmsg_probe() error: uninitialized symbol 'rpdev_ctrl'.
---
drivers/rpmsg/virtio_rpmsg_bus.c | 37 +++++++++++++++++++++++++++++++-
1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index e87d4cf926eb..5143fdeca306 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -813,6 +813,35 @@ static void rpmsg_xmit_done(struct virtqueue *svq)
wake_up_interruptible(&vrp->sendq);
}

+static struct rpmsg_device *rpmsg_virtio_add_char_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_ctrl_register_device(rpdev_ctrl);
+ if (err)
+ return ERR_PTR(err);
+
+ return rpdev_ctrl;
+}
+
static int rpmsg_probe(struct virtio_device *vdev)
{
vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
@@ -820,7 +849,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
struct virtqueue *vqs[2];
struct virtproc_info *vrp;
struct virtio_rpmsg_channel *vch;
- struct rpmsg_device *rpdev_ns;
+ struct rpmsg_device *rpdev_ns = NULL, *rpdev_ctrl = NULL;
void *bufs_va;
int err = 0, i;
size_t total_buf_space;
@@ -918,6 +947,11 @@ static int rpmsg_probe(struct virtio_device *vdev)
goto free_coherent;
}

+ rpdev_ctrl = rpmsg_virtio_add_char_dev(vdev);
+ if (IS_ERR(rpdev_ctrl)) {
+ err = PTR_ERR(rpdev_ctrl);
+ goto free_coherent;
+ }
/*
* Prepare to kick but don't notify yet - we can't do this before
* device is ready.
@@ -941,6 +975,7 @@ static int rpmsg_probe(struct virtio_device *vdev)

free_coherent:
kfree(vch);
+ kfree(to_virtio_rpmsg_channel(rpdev_ctrl));
dma_free_coherent(vdev->dev.parent, total_buf_space,
bufs_va, vrp->bufs_dma);
vqs_del:
--
2.17.1