// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2015, Sony Mobile Communications Inc.
 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/rpmsg.h>

#include "qrtr.h"

struct qrtr_smd_dev {
        struct qrtr_endpoint ep;
        struct rpmsg_endpoint *channel;
        struct device *dev;
};

/* from smd to qrtr */
static int qcom_smd_qrtr_callback(struct rpmsg_device *rpdev,
                                  void *data, int len, void *priv, u32 addr)
{
        struct qrtr_smd_dev *qdev = dev_get_drvdata(&rpdev->dev);
        int rc;

        if (!qdev)
                return -EAGAIN;

        rc = qrtr_endpoint_post(&qdev->ep, data, len);
        if (rc == -EINVAL) {
                dev_err(qdev->dev, "invalid ipcrouter packet\n");
                /* return 0 to let smd drop the packet */
                rc = 0;
        }

        return rc;
}

/* from qrtr to smd */
static int qcom_smd_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb)
{
        struct qrtr_smd_dev *qdev = container_of(ep, struct qrtr_smd_dev, ep);
        int rc;

        rc = skb_linearize(skb);
        if (rc)
                goto out;

        rc = rpmsg_send(qdev->channel, skb->data, skb->len);

out:
        if (rc)
                kfree_skb(skb);
        else
                consume_skb(skb);
        return rc;
}

static int qcom_smd_qrtr_probe(struct rpmsg_device *rpdev)
{
        struct qrtr_smd_dev *qdev;
        int rc;

        qdev = devm_kzalloc(&rpdev->dev, sizeof(*qdev), GFP_KERNEL);
        if (!qdev)
                return -ENOMEM;

        qdev->channel = rpdev->ept;
        qdev->dev = &rpdev->dev;
        qdev->ep.xmit = qcom_smd_qrtr_send;

        rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO);
        if (rc)
                return rc;

        dev_set_drvdata(&rpdev->dev, qdev);

        dev_dbg(&rpdev->dev, "Qualcomm SMD QRTR driver probed\n");

        return 0;
}

static void qcom_smd_qrtr_remove(struct rpmsg_device *rpdev)
{
        struct qrtr_smd_dev *qdev = dev_get_drvdata(&rpdev->dev);

        qrtr_endpoint_unregister(&qdev->ep);

        dev_set_drvdata(&rpdev->dev, NULL);
}

static const struct rpmsg_device_id qcom_smd_qrtr_smd_match[] = {
        { "IPCRTR" },
        {}
};

static struct rpmsg_driver qcom_smd_qrtr_driver = {
        .probe = qcom_smd_qrtr_probe,
        .remove = qcom_smd_qrtr_remove,
        .callback = qcom_smd_qrtr_callback,
        .id_table = qcom_smd_qrtr_smd_match,
        .drv = {
                .name = "qcom_smd_qrtr",
        },
};

module_rpmsg_driver(qcom_smd_qrtr_driver);

MODULE_ALIAS("rpmsg:IPCRTR");
MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
MODULE_LICENSE("GPL v2");