drivers/usb/usbip/vudc_main.c

   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
  15 static unsigned int vudc_number = 1;
  16
  17 module_param_named(num, vudc_number, uint, S_IRUGO);
  18 MODULE_PARM_DESC(num, "number of emulated controllers");
  19
  20 static struct platform_driver vudc_driver = {
  21         .probe          = vudc_probe,
  22         .remove         = vudc_remove,
  23         .driver         = {
  24                 .name   = GADGET_NAME,
  25         },
  26 };
  27
  28 static struct list_head vudc_devices = LIST_HEAD_INIT(vudc_devices);
  29
  30 static 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
  73 cleanup:
  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);
  85 out:
  86         return retval;
  87 }
  88 module_init(init);
  89
  90 static 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 }
 105 module_exit(cleanup);
 106
 107 MODULE_DESCRIPTION("USB over IP Device Controller");
 108 MODULE_AUTHOR("Krzysztof Opasiak, Karol Kosik, Igor Kotrasinski");
 109 MODULE_LICENSE("GPL");