LXR linux/samples/rpmsg/rpmsg_client

   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
  27struct instance_data {
  28        int rx_count;
  29};
  30
  31static int rpmsg_sample_cb(struct rpmsg_device *rpdev, void *data, int len,
  32                                                void *priv, u32 src)
  33{
  34        int ret;
  35        struct instance_data *idata = dev_get_drvdata(&rpdev->dev);
  36
  37        dev_info(&rpdev->dev, "incoming msg %d (src: 0x%x)\n",
  38                 ++idata->rx_count, src);
  39
  40        print_hex_dump(KERN_DEBUG, __func__, DUMP_PREFIX_NONE, 16, 1,
  41                       data, len,  true);
  42
  43        /* samples should not live forever */
  44        if (idata->rx_count >= MSG_LIMIT) {
  45                dev_info(&rpdev->dev, "goodbye!\n");
  46                return 0;
  47        }
  48
  49        /* send a new message now */
  50        ret = rpmsg_send(rpdev->ept, MSG, strlen(MSG));
  51        if (ret)
  52                dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);
  53
  54        return 0;
  55}
  56
  57static int rpmsg_sample_probe(struct rpmsg_device *rpdev)
  58{
  59        int ret;
  60        struct instance_data *idata;
  61
  62        dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
  63                                        rpdev->src, rpdev->dst);
  64
  65        idata = devm_kzalloc(&rpdev->dev, sizeof(*idata), GFP_KERNEL);
  66        if (!idata)
  67                return -ENOMEM;
  68
  69        dev_set_drvdata(&rpdev->dev, idata);
  70
  71        /* send a message to our remote processor */
  72        ret = rpmsg_send(rpdev->ept, MSG, strlen(MSG));
  73        if (ret) {
  74                dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", ret);
  75                return ret;
  76        }
  77
  78        return 0;
  79}
  80
  81static void rpmsg_sample_remove(struct rpmsg_device *rpdev)
  82{
  83        dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n");
  84}
  85
  86static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = {
  87        { .name = "rpmsg-client-sample" },
  88        { },
  89};
  90MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table);
  91
  92static struct rpmsg_driver rpmsg_sample_client = {
  93        .drv.name       = KBUILD_MODNAME,
  94        .id_table       = rpmsg_driver_sample_id_table,
  95        .probe          = rpmsg_sample_probe,
  96        .callback       = rpmsg_sample_cb,
  97        .remove         = rpmsg_sample_remove,
  98};
  99module_rpmsg_driver(rpmsg_sample_client);
 100
 101MODULE_DESCRIPTION("Remote processor messaging sample client driver");
 102MODULE_LICENSE("GPL v2");
 103