1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (C) STMicroelectronics 2020 - All Rights Reserved |
4 | */ |
5 | #include <linux/device.h> |
6 | #include <linux/kernel.h> |
7 | #include <linux/module.h> |
8 | #include <linux/rpmsg.h> |
9 | #include <linux/rpmsg/ns.h> |
10 | #include <linux/slab.h> |
11 | |
12 | #include "rpmsg_internal.h" |
13 | |
14 | /** |
15 | * rpmsg_ns_register_device() - register name service device based on rpdev |
16 | * @rpdev: prepared rpdev to be used for creating endpoints |
17 | * |
18 | * This function wraps rpmsg_register_device() preparing the rpdev for use as |
19 | * basis for the rpmsg name service device. |
20 | */ |
21 | int rpmsg_ns_register_device(struct rpmsg_device *rpdev) |
22 | { |
23 | rpdev->src = RPMSG_NS_ADDR; |
24 | rpdev->dst = RPMSG_NS_ADDR; |
25 | |
26 | return rpmsg_register_device_override(rpdev, driver_override: "rpmsg_ns" ); |
27 | } |
28 | EXPORT_SYMBOL(rpmsg_ns_register_device); |
29 | |
30 | /* invoked when a name service announcement arrives */ |
31 | static int rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len, |
32 | void *priv, u32 src) |
33 | { |
34 | struct rpmsg_ns_msg *msg = data; |
35 | struct rpmsg_device *newch; |
36 | struct rpmsg_channel_info chinfo; |
37 | struct device *dev = rpdev->dev.parent; |
38 | int ret; |
39 | |
40 | #if defined(CONFIG_DYNAMIC_DEBUG) |
41 | dynamic_hex_dump("NS announcement: " , DUMP_PREFIX_NONE, 16, 1, |
42 | data, len, true); |
43 | #endif |
44 | |
45 | if (len != sizeof(*msg)) { |
46 | dev_err(dev, "malformed ns msg (%d)\n" , len); |
47 | return -EINVAL; |
48 | } |
49 | |
50 | /* don't trust the remote processor for null terminating the name */ |
51 | msg->name[RPMSG_NAME_SIZE - 1] = '\0'; |
52 | |
53 | strscpy_pad(dest: chinfo.name, src: msg->name, count: sizeof(chinfo.name)); |
54 | chinfo.src = RPMSG_ADDR_ANY; |
55 | chinfo.dst = rpmsg32_to_cpu(rpdev, val: msg->addr); |
56 | |
57 | dev_info(dev, "%sing channel %s addr 0x%x\n" , |
58 | rpmsg32_to_cpu(rpdev, msg->flags) & RPMSG_NS_DESTROY ? |
59 | "destroy" : "creat" , msg->name, chinfo.dst); |
60 | |
61 | if (rpmsg32_to_cpu(rpdev, val: msg->flags) & RPMSG_NS_DESTROY) { |
62 | ret = rpmsg_release_channel(rpdev, chinfo: &chinfo); |
63 | if (ret) |
64 | dev_err(dev, "rpmsg_destroy_channel failed: %d\n" , ret); |
65 | } else { |
66 | newch = rpmsg_create_channel(rpdev, chinfo: &chinfo); |
67 | if (!newch) |
68 | dev_err(dev, "rpmsg_create_channel failed\n" ); |
69 | } |
70 | |
71 | return 0; |
72 | } |
73 | |
74 | static int rpmsg_ns_probe(struct rpmsg_device *rpdev) |
75 | { |
76 | struct rpmsg_endpoint *ns_ept; |
77 | struct rpmsg_channel_info ns_chinfo = { |
78 | .src = RPMSG_NS_ADDR, |
79 | .dst = RPMSG_NS_ADDR, |
80 | .name = "name_service" , |
81 | }; |
82 | |
83 | /* |
84 | * Create the NS announcement service endpoint associated to the RPMsg |
85 | * device. The endpoint will be automatically destroyed when the RPMsg |
86 | * device will be deleted. |
87 | */ |
88 | ns_ept = rpmsg_create_ept(rpdev, cb: rpmsg_ns_cb, NULL, chinfo: ns_chinfo); |
89 | if (!ns_ept) { |
90 | dev_err(&rpdev->dev, "failed to create the ns ept\n" ); |
91 | return -ENOMEM; |
92 | } |
93 | rpdev->ept = ns_ept; |
94 | |
95 | return 0; |
96 | } |
97 | |
98 | static struct rpmsg_driver rpmsg_ns_driver = { |
99 | .drv.name = KBUILD_MODNAME, |
100 | .probe = rpmsg_ns_probe, |
101 | }; |
102 | |
103 | static int rpmsg_ns_init(void) |
104 | { |
105 | int ret; |
106 | |
107 | ret = register_rpmsg_driver(&rpmsg_ns_driver); |
108 | if (ret < 0) |
109 | pr_err("%s: Failed to register rpmsg driver\n" , __func__); |
110 | |
111 | return ret; |
112 | } |
113 | postcore_initcall(rpmsg_ns_init); |
114 | |
115 | static void rpmsg_ns_exit(void) |
116 | { |
117 | unregister_rpmsg_driver(drv: &rpmsg_ns_driver); |
118 | } |
119 | module_exit(rpmsg_ns_exit); |
120 | |
121 | MODULE_DESCRIPTION("Name service announcement rpmsg driver" ); |
122 | MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>" ); |
123 | MODULE_ALIAS("rpmsg:" KBUILD_MODNAME); |
124 | MODULE_LICENSE("GPL v2" ); |
125 | |