net/qrtr/smd.c

   1 /*
   2  * Copyright (c) 2015, Sony Mobile Communications Inc.
   3  * Copyright (c) 2013, The Linux Foundation. All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 and
   7  * only version 2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/rpmsg.h>
  18
  19 #include "qrtr.h"
  20
  21 struct qrtr_smd_dev {
  22         struct qrtr_endpoint ep;
  23         struct rpmsg_endpoint *channel;
  24         struct device *dev;
  25 };
  26
  27 /* from smd to qrtr */
  28 static int qcom_smd_qrtr_callback(struct rpmsg_device *rpdev,
  29                                   void *data, int len, void *priv, u32 addr)
  30 {
  31         struct qrtr_smd_dev *qdev = dev_get_drvdata(&rpdev->dev);
  32         int rc;
  33
  34         if (!qdev)
  35                 return -EAGAIN;
  36
  37         rc = qrtr_endpoint_post(&qdev->ep, data, len);
  38         if (rc == -EINVAL) {
  39                 dev_err(qdev->dev, "invalid ipcrouter packet\n");
  40                 /* return 0 to let smd drop the packet */
  41                 rc = 0;
  42         }
  43
  44         return rc;
  45 }
  46
  47 /* from qrtr to smd */
  48 static int qcom_smd_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb)
  49 {
  50         struct qrtr_smd_dev *qdev = container_of(ep, struct qrtr_smd_dev, ep);
  51         int rc;
  52
  53         rc = skb_linearize(skb);
  54         if (rc)
  55                 goto out;
  56
  57         rc = rpmsg_send(qdev->channel, skb->data, skb->len);
  58
  59 out:
  60         if (rc)
  61                 kfree_skb(skb);
  62         else
  63                 consume_skb(skb);
  64         return rc;
  65 }
  66
  67 static int qcom_smd_qrtr_probe(struct rpmsg_device *rpdev)
  68 {
  69         struct qrtr_smd_dev *qdev;
  70         int rc;
  71
  72         qdev = devm_kzalloc(&rpdev->dev, sizeof(*qdev), GFP_KERNEL);
  73         if (!qdev)
  74                 return -ENOMEM;
  75
  76         qdev->channel = rpdev->ept;
  77         qdev->dev = &rpdev->dev;
  78         qdev->ep.xmit = qcom_smd_qrtr_send;
  79
  80         rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO);
  81         if (rc)
  82                 return rc;
  83
  84         dev_set_drvdata(&rpdev->dev, qdev);
  85
  86         dev_dbg(&rpdev->dev, "Qualcomm SMD QRTR driver probed\n");
  87
  88         return 0;
  89 }
  90
  91 static void qcom_smd_qrtr_remove(struct rpmsg_device *rpdev)
  92 {
  93         struct qrtr_smd_dev *qdev = dev_get_drvdata(&rpdev->dev);
  94
  95         qrtr_endpoint_unregister(&qdev->ep);
  96
  97         dev_set_drvdata(&rpdev->dev, NULL);
  98 }
  99
 100 static const struct rpmsg_device_id qcom_smd_qrtr_smd_match[] = {
 101         { "IPCRTR" },
 102         {}
 103 };
 104
 105 static struct rpmsg_driver qcom_smd_qrtr_driver = {
 106         .probe = qcom_smd_qrtr_probe,
 107         .remove = qcom_smd_qrtr_remove,
 108         .callback = qcom_smd_qrtr_callback,
 109         .id_table = qcom_smd_qrtr_smd_match,
 110         .drv = {
 111                 .name = "qcom_smd_qrtr",
 112         },
 113 };
 114
 115 module_rpmsg_driver(qcom_smd_qrtr_driver);
 116
 117 MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
 118 MODULE_LICENSE("GPL v2");