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         struct device *dev;
  25 };
  26
  27 /* from smd to qrtr */
  28 static int qcom_smd_qrtr_callback(struct qcom_smd_channel *channel,
  29                                   const void *data, size_t len)
  30 {
  31         struct qrtr_smd_dev *qdev = qcom_smd_get_drvdata(channel);
  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 = qcom_smd_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 qcom_smd_device *sdev)
  68 {
  69         struct qrtr_smd_dev *qdev;
  70         int rc;
  71
  72         qdev = devm_kzalloc(&sdev->dev, sizeof(*qdev), GFP_KERNEL);
  73         if (!qdev)
  74                 return -ENOMEM;
  75
  76         qdev->channel = sdev->channel;
  77         qdev->dev = &sdev->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         qcom_smd_set_drvdata(sdev->channel, qdev);
  85         dev_set_drvdata(&sdev->dev, qdev);
  86
  87         dev_dbg(&sdev->dev, "Qualcomm SMD QRTR driver probed\n");
  88
  89         return 0;
  90 }
  91
  92 static void qcom_smd_qrtr_remove(struct qcom_smd_device *sdev)
  93 {
  94         struct qrtr_smd_dev *qdev = dev_get_drvdata(&sdev->dev);
  95
  96         qrtr_endpoint_unregister(&qdev->ep);
  97
  98         dev_set_drvdata(&sdev->dev, NULL);
  99 }
 100
 101 static const struct qcom_smd_id qcom_smd_qrtr_smd_match[] = {
 102         { "IPCRTR" },
 103         {}
 104 };
 105
 106 static struct qcom_smd_driver qcom_smd_qrtr_driver = {
 107         .probe = qcom_smd_qrtr_probe,
 108         .remove = qcom_smd_qrtr_remove,
 109         .callback = qcom_smd_qrtr_callback,
 110         .smd_match_table = qcom_smd_qrtr_smd_match,
 111         .driver = {
 112                 .name = "qcom_smd_qrtr",
 113                 .owner = THIS_MODULE,
 114         },
 115 };
 116
 117 module_qcom_smd_driver(qcom_smd_qrtr_driver);
 118
 119 MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
 120 MODULE_LICENSE("GPL v2");