Merge branch 'for-5.4' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie...
[platform/kernel/linux-rpi.git] / samples / rpmsg / rpmsg_client_sample.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Remote processor messaging - sample client driver
4  *
5  * Copyright (C) 2011 Texas Instruments, Inc.
6  * Copyright (C) 2011 Google, Inc.
7  *
8  * Ohad Ben-Cohen <ohad@wizery.com>
9  * Brian Swetland <swetland@google.com>
10  */
11
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/rpmsg.h>
15
16 #define MSG             "hello world!"
17
18 static int count = 100;
19 module_param(count, int, 0644);
20
21 struct instance_data {
22         int rx_count;
23 };
24
25 static int rpmsg_sample_cb(struct rpmsg_device *rpdev, void *data, int len,
26                                                 void *priv, u32 src)
27 {
28         int ret;
29         struct instance_data *idata = dev_get_drvdata(&rpdev->dev);
30
31         dev_info(&rpdev->dev, "incoming msg %d (src: 0x%x)\n",
32                  ++idata->rx_count, src);
33
34         print_hex_dump_debug(__func__, DUMP_PREFIX_NONE, 16, 1, data, len,
35                              true);
36
37         /* samples should not live forever */
38         if (idata->rx_count >= count) {
39                 dev_info(&rpdev->dev, "goodbye!\n");
40                 return 0;
41         }
42
43         /* send a new message now */
44         ret = rpmsg_send(rpdev->ept, MSG, strlen(MSG));
45         if (ret)
46                 dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);
47
48         return 0;
49 }
50
51 static int rpmsg_sample_probe(struct rpmsg_device *rpdev)
52 {
53         int ret;
54         struct instance_data *idata;
55
56         dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
57                                         rpdev->src, rpdev->dst);
58
59         idata = devm_kzalloc(&rpdev->dev, sizeof(*idata), GFP_KERNEL);
60         if (!idata)
61                 return -ENOMEM;
62
63         dev_set_drvdata(&rpdev->dev, idata);
64
65         /* send a message to our remote processor */
66         ret = rpmsg_send(rpdev->ept, MSG, strlen(MSG));
67         if (ret) {
68                 dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);
69                 return ret;
70         }
71
72         return 0;
73 }
74
75 static void rpmsg_sample_remove(struct rpmsg_device *rpdev)
76 {
77         dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n");
78 }
79
80 static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = {
81         { .name = "rpmsg-client-sample" },
82         { },
83 };
84 MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table);
85
86 static struct rpmsg_driver rpmsg_sample_client = {
87         .drv.name       = KBUILD_MODNAME,
88         .id_table       = rpmsg_driver_sample_id_table,
89         .probe          = rpmsg_sample_probe,
90         .callback       = rpmsg_sample_cb,
91         .remove         = rpmsg_sample_remove,
92 };
93 module_rpmsg_driver(rpmsg_sample_client);
94
95 MODULE_DESCRIPTION("Remote processor messaging sample client driver");
96 MODULE_LICENSE("GPL v2");