drivers/uwb/umc-dev.c

   1 /*
   2  * UWB Multi-interface Controller device management.
   3  *
   4  * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
   5  *
   6  * This file is released under the GNU GPL v2.
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/uwb/umc.h>
  10 #define D_LOCAL 0
  11 #include <linux/uwb/debug.h>
  12
  13 static void umc_device_release(struct device *dev)
  14 {
  15         struct umc_dev *umc = to_umc_dev(dev);
  16
  17         kfree(umc);
  18 }
  19
  20 /**
  21  * umc_device_create - allocate a child UMC device
  22  * @parent: parent of the new UMC device.
  23  * @n:      index of the new device.
  24  *
  25  * The new UMC device will have a bus ID of the parent with '-n'
  26  * appended.
  27  */
  28 struct umc_dev *umc_device_create(struct device *parent, int n)
  29 {
  30         struct umc_dev *umc;
  31
  32         umc = kzalloc(sizeof(struct umc_dev), GFP_KERNEL);
  33         if (umc) {
  34                 snprintf(umc->dev.bus_id, sizeof(umc->dev.bus_id), "%s-%d",
  35                          parent->bus_id, n);
  36                 umc->dev.parent  = parent;
  37                 umc->dev.bus     = &umc_bus_type;
  38                 umc->dev.release = umc_device_release;
  39
  40                 umc->dev.dma_mask = parent->dma_mask;
  41         }
  42         return umc;
  43 }
  44 EXPORT_SYMBOL_GPL(umc_device_create);
  45
  46 /**
  47  * umc_device_register - register a UMC device
  48  * @umc: pointer to the UMC device
  49  *
  50  * The memory resource for the UMC device is acquired and the device
  51  * registered with the system.
  52  */
  53 int umc_device_register(struct umc_dev *umc)
  54 {
  55         int err;
  56
  57         d_fnstart(3, &umc->dev, "(umc_dev %p)\n", umc);
  58
  59         err = request_resource(umc->resource.parent, &umc->resource);
  60         if (err < 0) {
  61                 dev_err(&umc->dev, "can't allocate resource range "
  62                         "%016Lx to %016Lx: %d\n",
  63                         (unsigned long long)umc->resource.start,
  64                         (unsigned long long)umc->resource.end,
  65                         err);
  66                 goto error_request_resource;
  67         }
  68
  69         err = device_register(&umc->dev);
  70         if (err < 0)
  71                 goto error_device_register;
  72         d_fnend(3, &umc->dev, "(umc_dev %p) = 0\n", umc);
  73         return 0;
  74
  75 error_device_register:
  76         release_resource(&umc->resource);
  77 error_request_resource:
  78         d_fnend(3, &umc->dev, "(umc_dev %p) = %d\n", umc, err);
  79         return err;
  80 }
  81 EXPORT_SYMBOL_GPL(umc_device_register);
  82
  83 /**
  84  * umc_device_unregister - unregister a UMC device
  85  * @umc: pointer to the UMC device
  86  *
  87  * First we unregister the device, make sure the driver can do it's
  88  * resource release thing and then we try to release any left over
  89  * resources. We take a ref to the device, to make sure it doesn't
  90  * dissapear under our feet.
  91  */
  92 void umc_device_unregister(struct umc_dev *umc)
  93 {
  94         struct device *dev;
  95         if (!umc)
  96                 return;
  97         dev = get_device(&umc->dev);
  98         d_fnstart(3, dev, "(umc_dev %p)\n", umc);
  99         device_unregister(&umc->dev);
 100         release_resource(&umc->resource);
 101         d_fnend(3, dev, "(umc_dev %p) = void\n", umc);
 102         put_device(dev);
 103 }
 104 EXPORT_SYMBOL_GPL(umc_device_unregister);