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