[PATCH V6 3/5] rpmsg: glink: Add support for rpmsg glink chrdev

From: Arun Kumar Neelakantam
Date: Wed May 20 2020 - 05:40:25 EST


From: Chris Lew <clew@xxxxxxxxxxxxxx>

RPMSG provides a char device interface to userspace. Probe the rpmsg
chrdev channel to enable the rpmsg_ctrl device creation on glink
transports.

Signed-off-by: Chris Lew <clew@xxxxxxxxxxxxxx>
Signed-off-by: Arun Kumar Neelakantam <aneela@xxxxxxxxxxxxxx>
---
drivers/rpmsg/qcom_glink_native.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index ea2f33f..b85433c 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -1574,6 +1574,40 @@ static void qcom_glink_cancel_rx_work(struct qcom_glink *glink)
kfree(dcmd);
}

+static void qcom_glink_device_release(struct device *dev)
+{
+ struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+ struct glink_channel *channel = to_glink_channel(rpdev->ept);
+
+ /* Release qcom_glink_alloc_channel() reference */
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+ kfree(rpdev);
+}
+
+static int qcom_glink_create_chrdev(struct qcom_glink *glink)
+{
+ struct rpmsg_device *rpdev;
+ struct glink_channel *channel;
+
+ rpdev = kzalloc(sizeof(*rpdev), GFP_KERNEL);
+ if (!rpdev)
+ return -ENOMEM;
+
+ channel = qcom_glink_alloc_channel(glink, "rpmsg_chrdev");
+ if (IS_ERR(channel)) {
+ kfree(rpdev);
+ return PTR_ERR(channel);
+ }
+ channel->rpdev = rpdev;
+
+ rpdev->ept = &channel->ept;
+ rpdev->ops = &glink_device_ops;
+ rpdev->dev.parent = glink->dev;
+ rpdev->dev.release = qcom_glink_device_release;
+
+ return rpmsg_chrdev_register_device(rpdev);
+}
+
struct qcom_glink *qcom_glink_native_probe(struct device *dev,
unsigned long features,
struct qcom_glink_pipe *rx,
@@ -1633,6 +1667,10 @@ struct qcom_glink *qcom_glink_native_probe(struct device *dev,
if (ret)
return ERR_PTR(ret);

+ ret = qcom_glink_create_chrdev(glink);
+ if (ret)
+ dev_err(glink->dev, "failed to register chrdev\n");
+
return glink;
}
EXPORT_SYMBOL_GPL(qcom_glink_native_probe);
--
2.7.4