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/soc/qcom/smd.h>
  18
  19 #include "qrtr.h"
  20
  21 struct qrtr_smd_dev {
  22         struct qrtr_endpoint ep;
  23         struct qcom_smd_channel *channel;
  24 };
  25
  26 /* from smd to qrtr */
  27 static int qcom_smd_qrtr_callback(struct qcom_smd_device *sdev,
  28                                   const void *data, size_t len)
  29 {
  30         struct qrtr_smd_dev *qdev = dev_get_drvdata(&sdev->dev);
  31         int rc;
  32
  33         if (!qdev)
  34                 return -EAGAIN;
  35
  36         rc = qrtr_endpoint_post(&qdev->ep, data, len);
  37         if (rc == -EINVAL) {
  38                 dev_err(&sdev->dev, "invalid ipcrouter packet\n");
  39                 /* return 0 to let smd drop the packet */
  40                 rc = 0;
  41         }
  42
  43         return rc;
  44 }
  45
  46 /* from qrtr to smd */
  47 static int qcom_smd_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb)
  48 {
  49         struct qrtr_smd_dev *qdev = container_of(ep, struct qrtr_smd_dev, ep);
  50         int rc;
  51
  52         rc = skb_linearize(skb);
  53         if (rc)
  54                 goto out;
  55
  56         rc = qcom_smd_send(qdev->channel, skb->data, skb->len);
  57
  58 out:
  59         if (rc)
  60                 kfree_skb(skb);
  61         else
  62                 consume_skb(skb);
  63         return rc;
  64 }
  65
  66 static int qcom_smd_qrtr_probe(struct qcom_smd_device *sdev)
  67 {
  68         struct qrtr_smd_dev *qdev;
  69         int rc;
  70
  71         qdev = devm_kzalloc(&sdev->dev, sizeof(*qdev), GFP_KERNEL);
  72         if (!qdev)
  73                 return -ENOMEM;
  74
  75         qdev->channel = sdev->channel;
  76         qdev->ep.xmit = qcom_smd_qrtr_send;
  77
  78         rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO);
  79         if (rc)
  80                 return rc;
  81
  82         dev_set_drvdata(&sdev->dev, qdev);
  83
  84         dev_dbg(&sdev->dev, "Qualcomm SMD QRTR driver probed\n");
  85
  86         return 0;
  87 }
  88
  89 static void qcom_smd_qrtr_remove(struct qcom_smd_device *sdev)
  90 {
  91         struct qrtr_smd_dev *qdev = dev_get_drvdata(&sdev->dev);
  92
  93         qrtr_endpoint_unregister(&qdev->ep);
  94
  95         dev_set_drvdata(&sdev->dev, NULL);
  96 }
  97
  98 static const struct qcom_smd_id qcom_smd_qrtr_smd_match[] = {
  99         { "IPCRTR" },
 100         {}
 101 };
 102
 103 static struct qcom_smd_driver qcom_smd_qrtr_driver = {
 104         .probe = qcom_smd_qrtr_probe,
 105         .remove = qcom_smd_qrtr_remove,
 106         .callback = qcom_smd_qrtr_callback,
 107         .smd_match_table = qcom_smd_qrtr_smd_match,
 108         .driver = {
 109                 .name = "qcom_smd_qrtr",
 110                 .owner = THIS_MODULE,
 111         },
 112 };
 113
 114 module_qcom_smd_driver(qcom_smd_qrtr_driver);
 115
 116 MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
 117 MODULE_LICENSE("GPL v2");