LXR linux/drivers/usb/usbip/vudc

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2015 Karol Kosik <karo9@interia.eu>
   4 * Copyright (C) 2015-2016 Samsung Electronics
   5 *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
   6 *               Krzysztof Opasiak <k.opasiak@samsung.com>
   7 */
   8
   9#include <linux/device.h>
  10#include <linux/list.h>
  11#include <linux/module.h>
  12
  13#include "vudc.h"
  14
  15static unsigned int vudc_number = 1;
  16
  17module_param_named(num, vudc_number, uint, S_IRUGO);
  18MODULE_PARM_DESC(num, "number of emulated controllers");
  19
  20static struct platform_driver vudc_driver = {
  21        .probe          = vudc_probe,
  22        .remove         = vudc_remove,
  23        .driver         = {
  24                .name   = GADGET_NAME,
  25                .dev_groups = vudc_groups,
  26        },
  27};
  28
  29static struct list_head vudc_devices = LIST_HEAD_INIT(vudc_devices);
  30
  31static int __init init(void)
  32{
  33        int retval = -ENOMEM;
  34        int i;
  35        struct vudc_device *udc_dev = NULL, *udc_dev2 = NULL;
  36
  37        if (usb_disabled())
  38                return -ENODEV;
  39
  40        if (vudc_number < 1) {
  41                pr_err("Number of emulated UDC must be no less than 1");
  42                return -EINVAL;
  43        }
  44
  45        retval = platform_driver_register(&vudc_driver);
  46        if (retval < 0)
  47                goto out;
  48
  49        for (i = 0; i < vudc_number; i++) {
  50                udc_dev = alloc_vudc_device(i);
  51                if (!udc_dev) {
  52                        retval = -ENOMEM;
  53                        goto cleanup;
  54                }
  55
  56                retval = platform_device_add(udc_dev->pdev);
  57                if (retval < 0) {
  58                        put_vudc_device(udc_dev);
  59                        goto cleanup;
  60                }
  61
  62                list_add_tail(&udc_dev->dev_entry, &vudc_devices);
  63                if (!platform_get_drvdata(udc_dev->pdev)) {
  64                        /*
  65                         * The udc was added successfully but its probe
  66                         * function failed for some reason.
  67                         */
  68                        retval = -EINVAL;
  69                        goto cleanup;
  70                }
  71        }
  72        goto out;
  73
  74cleanup:
  75        list_for_each_entry_safe(udc_dev, udc_dev2, &vudc_devices, dev_entry) {
  76                list_del(&udc_dev->dev_entry);
  77                /*
  78                 * Just do platform_device_del() here, put_vudc_device()
  79                 * calls the platform_device_put()
  80                 */
  81                platform_device_del(udc_dev->pdev);
  82                put_vudc_device(udc_dev);
  83        }
  84
  85        platform_driver_unregister(&vudc_driver);
  86out:
  87        return retval;
  88}
  89module_init(init);
  90
  91static void __exit cleanup(void)
  92{
  93        struct vudc_device *udc_dev = NULL, *udc_dev2 = NULL;
  94
  95        list_for_each_entry_safe(udc_dev, udc_dev2, &vudc_devices, dev_entry) {
  96                list_del(&udc_dev->dev_entry);
  97                /*
  98                 * Just do platform_device_del() here, put_vudc_device()
  99                 * calls the platform_device_put()
 100                 */
 101                platform_device_del(udc_dev->pdev);
 102                put_vudc_device(udc_dev);
 103        }
 104        platform_driver_unregister(&vudc_driver);
 105}
 106module_exit(cleanup);
 107
 108MODULE_DESCRIPTION("USB over IP Device Controller");
 109MODULE_AUTHOR("Krzysztof Opasiak, Karol Kosik, Igor Kotrasinski");
 110MODULE_LICENSE("GPL");
 111