samples/rpmsg: add an rpmsg driver sample

	  Build an example of how to dynamically add the hello

	  command to the kdb shell.

config SAMPLE_RPMSG_CLIENT

	tristate "Build rpmsg client sample -- loadable modules only"

	depends on RPMSG && m

	help

	  Build an rpmsg client sample driver, which demonstrates how

	  to communicate with an AMP-configured remote processor over

	  the rpmsg bus.

endif # SAMPLES

# Makefile for Linux samples code

obj-$(CONFIG_SAMPLES)	+= kobject/ kprobes/ tracepoints/ trace_events/ \

			   hw_breakpoint/ kfifo/ kdb/ hidraw/

			   hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/

obj-$(CONFIG_SAMPLE_RPMSG_CLIENT) += rpmsg_client_sample.o

/*

 * Remote processor messaging - sample client driver

 *

 * Copyright (C) 2011 Texas Instruments, Inc.

 * Copyright (C) 2011 Google, Inc.

 *

 * Ohad Ben-Cohen <ohad@wizery.com>

 * Brian Swetland <swetland@google.com>

 *

 * This software is licensed under the terms of the GNU General Public

 * License version 2, as published by the Free Software Foundation, and

 * may be copied, distributed, and modified under those terms.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/rpmsg.h>

#define MSG		"hello world!"

#define MSG_LIMIT	100

static void rpmsg_sample_cb(struct rpmsg_channel *rpdev, void *data, int len,

						void *priv, u32 src)

{

	int ret;

	static int rx_count;

	dev_info(&rpdev->dev, "incoming msg %d (src: 0x%x)\n", ++rx_count, src);

	print_hex_dump(KERN_DEBUG, __func__, DUMP_PREFIX_NONE, 16, 1,

		       data, len,  true);

	/* samples should not live forever */

	if (rx_count >= MSG_LIMIT) {

		dev_info(&rpdev->dev, "goodbye!\n");

		return;

	}

	/* send a new message now */

	ret = rpmsg_send(rpdev, MSG, strlen(MSG));

	if (ret)

		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);

}

static int rpmsg_sample_probe(struct rpmsg_channel *rpdev)

{

	int ret;

	dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",

					rpdev->src, rpdev->dst);

	/* send a message to our remote processor */

	ret = rpmsg_send(rpdev, MSG, strlen(MSG));

	if (ret) {

		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);

		return ret;

	}

	return 0;

}

static void __devexit rpmsg_sample_remove(struct rpmsg_channel *rpdev)

{

	dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n");

}

static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = {

	{ .name	= "rpmsg-client-sample" },

	{ },

};

MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table);

static struct rpmsg_driver rpmsg_sample_client = {

	.drv.name	= KBUILD_MODNAME,

	.drv.owner	= THIS_MODULE,

	.id_table	= rpmsg_driver_sample_id_table,

	.probe		= rpmsg_sample_probe,

	.callback	= rpmsg_sample_cb,

	.remove		= __devexit_p(rpmsg_sample_remove),

};

static int __init rpmsg_client_sample_init(void)

{

	return register_rpmsg_driver(&rpmsg_sample_client);

}

module_init(rpmsg_client_sample_init);

static void __exit rpmsg_client_sample_fini(void)

{

	unregister_rpmsg_driver(&rpmsg_sample_client);

}

module_exit(rpmsg_client_sample_fini);

MODULE_DESCRIPTION("Remote processor messaging sample client driver");

MODULE_LICENSE("GPL v2");