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        },
  26};
  27
  28static struct list_head vudc_devices = LIST_HEAD_INIT(vudc_devices);
  29
  30static int __init init(void)
  31{
  32        int retval = -ENOMEM;
  33        int i;
  34        struct vudc_device *udc_dev = NULL, *udc_dev2 = NULL;
  35
  36        if (usb_disabled())
  37                return -ENODEV;
  38
  39        if (vudc_number < 1) {
  40                pr_err("Number of emulated UDC must be no less than 1");
  41                return -EINVAL;
  42        }
  43
  44        retval = platform_driver_register(&vudc_driver);
  45        if (retval < 0)
  46                goto out;
  47
  48        for (i = 0; i < vudc_number; i++) {
  49                udc_dev = alloc_vudc_device(i);
  50                if (!udc_dev) {
  51                        retval = -ENOMEM;
  52                        goto cleanup;
  53                }
  54
  55                retval = platform_device_add(udc_dev->pdev);
  56                if (retval < 0) {
  57                        put_vudc_device(udc_dev);
  58                        goto cleanup;
  59                }
  60
  61                list_add_tail(&udc_dev->dev_entry, &vudc_devices);
  62                if (!platform_get_drvdata(udc_dev->pdev)) {
  63                        /*
  64                         * The udc was added successfully but its probe
  65                         * function failed for some reason.
  66                         */
  67                        retval = -EINVAL;
  68                        goto cleanup;
  69                }
  70        }
  71        goto out;
  72
  73cleanup:
  74        list_for_each_entry_safe(udc_dev, udc_dev2, &vudc_devices, dev_entry) {
  75                list_del(&udc_dev->dev_entry);
  76                /*
  77                 * Just do platform_device_del() here, put_vudc_device()
  78                 * calls the platform_device_put()
  79                 */
  80                platform_device_del(udc_dev->pdev);
  81                put_vudc_device(udc_dev);
  82        }
  83
  84        platform_driver_unregister(&vudc_driver);
  85out:
  86        return retval;
  87}
  88module_init(init);
  89
  90static void __exit cleanup(void)
  91{
  92        struct vudc_device *udc_dev = NULL, *udc_dev2 = NULL;
  93
  94        list_for_each_entry_safe(udc_dev, udc_dev2, &vudc_devices, dev_entry) {
  95                list_del(&udc_dev->dev_entry);
  96                /*
  97                 * Just do platform_device_del() here, put_vudc_device()
  98                 * calls the platform_device_put()
  99                 */
 100                platform_device_del(udc_dev->pdev);
 101                put_vudc_device(udc_dev);
 102        }
 103        platform_driver_unregister(&vudc_driver);
 104}
 105module_exit(cleanup);
 106
 107MODULE_DESCRIPTION("USB over IP Device Controller");
 108MODULE_AUTHOR("Krzysztof Opasiak, Karol Kosik, Igor Kotrasinski");
 109MODULE_LICENSE("GPL");
 110