1/*
  2 * Remote processor messaging - sample client driver
  3 *
  4 * Copyright (C) 2011 Texas Instruments, Inc.
  5 * Copyright (C) 2011 Google, Inc.
  6 *
  7 * Ohad Ben-Cohen <ohad@wizery.com>
  8 * Brian Swetland <swetland@google.com>
  9 *
 10 * This software is licensed under the terms of the GNU General Public
 11 * License version 2, as published by the Free Software Foundation, and
 12 * may be copied, distributed, and modified under those terms.
 13 *
 14 * This program is distributed in the hope that it will be useful,
 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 * GNU General Public License for more details.
 18 */
 19
 20#include <linux/kernel.h>
 21#include <linux/module.h>
 22#include <linux/rpmsg.h>
 23
 24#define MSG		"hello world!"
 25#define MSG_LIMIT	100
 26
 27static void rpmsg_sample_cb(struct rpmsg_channel *rpdev, void *data, int len,
 28						void *priv, u32 src)
 29{
 30	int ret;
 31	static int rx_count;
 32
 33	dev_info(&rpdev->dev, "incoming msg %d (src: 0x%x)\n", ++rx_count, src);
 34
 35	print_hex_dump(KERN_DEBUG, __func__, DUMP_PREFIX_NONE, 16, 1,
 36		       data, len,  true);
 37
 38	/* samples should not live forever */
 39	if (rx_count >= MSG_LIMIT) {
 40		dev_info(&rpdev->dev, "goodbye!\n");
 41		return;
 42	}
 43
 44	/* send a new message now */
 45	ret = rpmsg_send(rpdev, MSG, strlen(MSG));
 46	if (ret)
 47		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);
 48}
 49
 50static int rpmsg_sample_probe(struct rpmsg_channel *rpdev)
 51{
 52	int ret;
 53
 54	dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
 55					rpdev->src, rpdev->dst);
 56
 57	/* send a message to our remote processor */
 58	ret = rpmsg_send(rpdev, MSG, strlen(MSG));
 59	if (ret) {
 60		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);
 61		return ret;
 62	}
 63
 64	return 0;
 65}
 66
 67static void rpmsg_sample_remove(struct rpmsg_channel *rpdev)
 68{
 69	dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n");
 70}
 71
 72static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = {
 73	{ .name	= "rpmsg-client-sample" },
 74	{ },
 75};
 76MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table);
 77
 78static struct rpmsg_driver rpmsg_sample_client = {
 79	.drv.name	= KBUILD_MODNAME,
 80	.drv.owner	= THIS_MODULE,
 81	.id_table	= rpmsg_driver_sample_id_table,
 82	.probe		= rpmsg_sample_probe,
 83	.callback	= rpmsg_sample_cb,
 84	.remove		= rpmsg_sample_remove,
 85};
 86
 87static int __init rpmsg_client_sample_init(void)
 88{
 89	return register_rpmsg_driver(&rpmsg_sample_client);
 90}
 91module_init(rpmsg_client_sample_init);
 92
 93static void __exit rpmsg_client_sample_fini(void)
 94{
 95	unregister_rpmsg_driver(&rpmsg_sample_client);
 96}
 97module_exit(rpmsg_client_sample_fini);
 98
 99MODULE_DESCRIPTION("Remote processor messaging sample client driver");
100MODULE_LICENSE("GPL v2");