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/export.h>
  10#include <linux/slab.h>
  11#include <linux/uwb/umc.h>
  12
  13static 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 */
  28struct 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                dev_set_name(&umc->dev, "%s-%d", dev_name(parent), n);
  35                umc->dev.parent  = parent;
  36                umc->dev.bus     = &umc_bus_type;
  37                umc->dev.release = umc_device_release;
  38
  39                umc->dev.dma_mask = parent->dma_mask;
  40        }
  41        return umc;
  42}
  43EXPORT_SYMBOL_GPL(umc_device_create);
  44
  45/**
  46 * umc_device_register - register a UMC device
  47 * @umc: pointer to the UMC device
  48 *
  49 * The memory resource for the UMC device is acquired and the device
  50 * registered with the system.
  51 */
  52int umc_device_register(struct umc_dev *umc)
  53{
  54        int err;
  55
  56        err = request_resource(umc->resource.parent, &umc->resource);
  57        if (err < 0) {
  58                dev_err(&umc->dev, "can't allocate resource range %pR: %d\n",
  59                        &umc->resource, err);
  60                goto error_request_resource;
  61        }
  62
  63        err = device_register(&umc->dev);
  64        if (err < 0)
  65                goto error_device_register;
  66        return 0;
  67
  68error_device_register:
  69        release_resource(&umc->resource);
  70error_request_resource:
  71        return err;
  72}
  73EXPORT_SYMBOL_GPL(umc_device_register);
  74
  75/**
  76 * umc_device_unregister - unregister a UMC device
  77 * @umc: pointer to the UMC device
  78 *
  79 * First we unregister the device, make sure the driver can do it's
  80 * resource release thing and then we try to release any left over
  81 * resources. We take a ref to the device, to make sure it doesn't
  82 * disappear under our feet.
  83 */
  84void umc_device_unregister(struct umc_dev *umc)
  85{
  86        struct device *dev;
  87        if (!umc)
  88                return;
  89        dev = get_device(&umc->dev);
  90        device_unregister(&umc->dev);
  91        release_resource(&umc->resource);
  92        put_device(dev);
  93}
  94EXPORT_SYMBOL_GPL(umc_device_unregister);
  95