xref: /openbmc/linux/net/qrtr/smd.c (revision f3539c12)
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");
121