GNU Linux-libre 4.19.211-gnu1
[releases.git] / 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_ALIAS("rpmsg:IPCRTR");
118 MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
119 MODULE_LICENSE("GPL v2");