static void brcmf_fw_request_code_done(const struct firmware *fw, void *ctx)
{
	struct brcmf_fw *fwctx = ctx;
	int ret;

	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
	if (!fw)
		goto fail;

	/* only requested code so done here */
	if (!(fwctx->flags & BRCMF_FW_REQUEST_NVRAM)) {
		fwctx->done(fwctx->dev, fw, NULL, 0);
		kfree(fwctx);
		return;
	}
	fwctx->code = fw;
	ret = request_firmware_nowait(THIS_MODULE, true, fwctx->nvram_name,
				      fwctx->dev, GFP_KERNEL, fwctx,
				      brcmf_fw_request_nvram_done);

	if (!ret)
		return;

	brcmf_fw_request_nvram_done(NULL, fwctx);
	return;

fail:
	brcmf_dbg(TRACE, "failed: dev=%s\n", dev_name(fwctx->dev));
	device_release_driver(fwctx->dev);
	kfree(fwctx);
}

static void ar9170_usb_firmware_failed(struct ar9170_usb *aru)
{
	struct device *parent = aru->udev->dev.parent;
	struct usb_device *udev;

	/*
	 * Store a copy of the usb_device pointer locally.
	 * This is because device_release_driver initiates
	 * ar9170_usb_disconnect, which in turn frees our
	 * driver context (aru).
	 */
	udev = aru->udev;

	complete(&aru->firmware_loading_complete);

	/* unbind anything failed */
	if (parent)
		down(&parent->sem);

	device_release_driver(&udev->dev);
	if (parent)
		up(&parent->sem);

	usb_put_dev(udev);
}

/**
 * bus_remove_device - remove device from bus
 * @dev: device to be removed
 *
 * - Remove device from all interfaces.
 * - Remove symlink from bus' directory.
 * - Delete device from bus's list.
 * - Detach from its driver.
 * - Drop reference taken in bus_add_device().
 */
void bus_remove_device(struct device *dev)
{
    struct bus_type *bus = dev->bus;
    struct subsys_interface *sif;

    if (!bus)
        return;

    mutex_lock(&bus->p->mutex);
    list_for_each_entry(sif, &bus->p->interfaces, node)
    if (sif->remove_dev)
        sif->remove_dev(dev, sif);
    mutex_unlock(&bus->p->mutex);

    sysfs_remove_link(&dev->kobj, "subsystem");
    sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
                      dev_name(dev));
    device_remove_attrs(dev->bus, dev);
    if (klist_node_attached(&dev->p->knode_bus))
        klist_del(&dev->p->knode_bus);

    pr_debug("bus: '%s': remove device %s\n",
             dev->bus->name, dev_name(dev));
    device_release_driver(dev);
    bus_put(dev->bus);
}

static void brcmf_pcie_setup(struct device *dev, const struct firmware *fw,
			     void *nvram, u32 nvram_len)
{
	struct brcmf_bus *bus = dev_get_drvdata(dev);
	struct brcmf_pciedev *pcie_bus_dev = bus->bus_priv.pcie;
	struct brcmf_pciedev_info *devinfo = pcie_bus_dev->devinfo;
	struct brcmf_commonring **flowrings;
	int ret;
	u32 i;

	brcmf_pcie_attach(devinfo);

	ret = brcmf_pcie_download_fw_nvram(devinfo, fw, nvram, nvram_len);
	if (ret)
		goto fail;

	devinfo->state = BRCMFMAC_PCIE_STATE_UP;

	ret = brcmf_pcie_init_ringbuffers(devinfo);
	if (ret)
		goto fail;

	ret = brcmf_pcie_init_scratchbuffers(devinfo);
	if (ret)
		goto fail;

	brcmf_pcie_select_core(devinfo, BCMA_CORE_PCIE2);
	ret = brcmf_pcie_request_irq(devinfo);
	if (ret)
		goto fail;

	/* hook the commonrings in the bus structure. */
	for (i = 0; i < BRCMF_NROF_COMMON_MSGRINGS; i++)
		bus->msgbuf->commonrings[i] =
				&devinfo->shared.commonrings[i]->commonring;

	flowrings = kcalloc(devinfo->shared.nrof_flowrings, sizeof(flowrings),
			    GFP_KERNEL);
	if (!flowrings)
		goto fail;

	for (i = 0; i < devinfo->shared.nrof_flowrings; i++)
		flowrings[i] = &devinfo->shared.flowrings[i].commonring;
	bus->msgbuf->flowrings = flowrings;

	bus->msgbuf->rx_dataoffset = devinfo->shared.rx_dataoffset;
	bus->msgbuf->max_rxbufpost = devinfo->shared.max_rxbufpost;
	bus->msgbuf->nrof_flowrings = devinfo->shared.nrof_flowrings;

	init_waitqueue_head(&devinfo->mbdata_resp_wait);

	brcmf_pcie_intr_enable(devinfo);
	if (brcmf_pcie_attach_bus(bus->dev) == 0)
		return;

	brcmf_pcie_bus_console_read(devinfo);

fail:
	device_release_driver(dev);
}

static void carl9170_usb_firmware_failed(struct ar9170 *ar)
{
	struct device *parent = ar->udev->dev.parent;
	struct usb_device *udev;

	/*
	 * Store a copy of the usb_device pointer locally.
	 * This is because device_release_driver initiates
	 * carl9170_usb_disconnect, which in turn frees our
	 * driver context (ar).
	 */
	udev = ar->udev;

	complete(&ar->fw_load_wait);

	/* unbind anything failed */
	if (parent)
		device_lock(parent);

	device_release_driver(&udev->dev);
	if (parent)
		device_unlock(parent);

	usb_put_dev(udev);
}

/**
 * device_reprobe - remove driver for a device and probe for a new driver
 * @dev: the device to reprobe
 *
 * This function detaches the attached driver (if any) for the given
 * device and restarts the driver probing process.  It is intended
 * to use if probing criteria changed during a devices lifetime and
 * driver attachment should change accordingly.
 */
int device_reprobe(struct device *dev)
{
	if (dev->driver) {
		if (dev->parent)        /* Needed for USB */
			down(&dev->parent->sem);
		device_release_driver(dev);
		if (dev->parent)
			up(&dev->parent->sem);
	}
	return bus_rescan_devices_helper(dev, NULL);
}

/**
 * phy_detach - detach a PHY device from its network device
 * @phydev: target phy_device struct
 */
void phy_detach(struct phy_device *phydev)
{
	phydev->attached_dev = NULL;

	/* If the device had no specific driver before (i.e. - it
	 * was using the generic driver), we unbind the device
	 * from the generic driver so that there's a chance a
	 * real driver could be loaded */
	if (phydev->dev.driver == &genphy_driver.driver)
		device_release_driver(&phydev->dev);
}

/**
 *	bus_remove_device - remove device from bus
 *	@dev:	device to be removed
 *
 *	- Remove symlink from bus's directory.
 *	- Delete device from bus's list.
 *	- Detach from its driver.
 *	- Drop reference taken in bus_add_device().
 */
void bus_remove_device(struct device * dev)
{
	if (dev->bus) {
		sysfs_remove_link(&dev->kobj, "bus");
		sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id);
		device_remove_attrs(dev->bus, dev);
		klist_remove(&dev->knode_bus);
		pr_debug("bus %s: remove device %s\n", dev->bus->name, dev->bus_id);
		device_release_driver(dev);
		put_bus(dev->bus);
	}
}

static void p54p_firmware_step2(const struct firmware *fw,
				void *context)
{
	struct p54p_priv *priv = context;
	struct ieee80211_hw *dev = priv->common.hw;
	struct pci_dev *pdev = priv->pdev;
	int err;

	if (!fw) {
		dev_err(&pdev->dev, "Cannot find firmware (isl3886pci)\n");
		err = -ENOENT;
		goto out;
	}

	priv->firmware = fw;

	err = p54p_open(dev);
	if (err)
		goto out;
	err = p54_read_eeprom(dev);
	p54p_stop(dev);
	if (err)
		goto out;

	err = p54_register_common(dev, &pdev->dev);
	if (err)
		goto out;

out:

	complete(&priv->fw_loaded);

	if (err) {
		struct device *parent = pdev->dev.parent;

		if (parent)
			device_lock(parent);

		/*
		 * This will indirectly result in a call to p54p_remove.
		 * Hence, we don't need to bother with freeing any
		 * allocated ressources at all.
		 */
		device_release_driver(&pdev->dev);

		if (parent)
			device_unlock(parent);
	}

	pci_dev_put(pdev);
}

static void pci_stop_dev(struct pci_dev *dev)
{
	pci_pme_active(dev, false);

	if (dev->is_added) {
		pci_proc_detach_device(dev);
		pci_remove_sysfs_dev_files(dev);
		device_release_driver(&dev->dev);
		dev->is_added = 0;
	}

	if (dev->bus->self)
		pcie_aspm_exit_link_state(dev);
}

static int umc_bus_pre_reset_helper(struct device *dev, void *data)
{
	int ret = 0;

	if (dev->driver) {
		struct umc_dev *umc = to_umc_dev(dev);
		struct umc_driver *umc_drv = to_umc_driver(dev->driver);

		if (umc_drv->pre_reset)
			ret = umc_drv->pre_reset(umc);
		else
			device_release_driver(dev);
	}
	return ret;
}

static void ar9170_usb_firmware_failed(struct ar9170_usb *aru)
{
	struct device *parent = aru->udev->dev.parent;

	complete(&aru->firmware_loading_complete);

	/* unbind anything failed */
	if (parent)
		device_lock(parent);
	device_release_driver(&aru->udev->dev);
	if (parent)
		device_unlock(parent);

	usb_put_dev(aru->udev);
}

void pci_stop_root_bus(struct pci_bus *bus)
{
	struct pci_dev *child, *tmp;
	struct pci_host_bridge *host_bridge;

	if (!pci_is_root_bus(bus))
		return;

	host_bridge = to_pci_host_bridge(bus->bridge);
	list_for_each_entry_safe_reverse(child, tmp,
					 &bus->devices, bus_list)
		pci_stop_bus_device(child);

	/* stop the host bridge */
	device_release_driver(&host_bridge->dev);
}

/**
 *	bus_remove_device - remove device from bus
 *	@dev:	device to be removed
 *
 *	- Remove symlink from bus's directory.
 *	- Delete device from bus's list.
 *	- Detach from its driver.
 *	- Drop reference taken in bus_add_device().
 */
void bus_remove_device(struct device * dev)
{
	if (dev->bus) {
		sysfs_remove_link(&dev->kobj, "subsystem");
		remove_deprecated_bus_links(dev);
		sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id);
		device_remove_attrs(dev->bus, dev);
		if (dev->is_registered) {
			dev->is_registered = 0;
			klist_del(&dev->knode_bus);
		}
		pr_debug("bus %s: remove device %s\n", dev->bus->name, dev->bus_id);
		device_release_driver(dev);
		put_bus(dev->bus);
	}
}

/**
 * bus_remove_device - remove device from bus
 * @dev: device to be removed
 *
 * - Remove symlink from bus's directory.
 * - Delete device from bus's list.
 * - Detach from its driver.
 * - Drop reference taken in bus_add_device().
 */
void bus_remove_device(struct device *dev)
{
	if (dev->bus) {
		sysfs_remove_link(&dev->kobj, "subsystem");
		sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
				  dev_name(dev));
		device_remove_attrs(dev->bus, dev);
		if (klist_node_attached(&dev->p->knode_bus))
			klist_del(&dev->p->knode_bus);

		pr_debug("bus: '%s': remove device %s\n",
			 dev->bus->name, dev_name(dev));
		device_release_driver(dev);
		bus_put(dev->bus);
	}
}

static ssize_t driver_unbind(struct device_driver *drv,
			     const char *buf, size_t count)
{
	struct bus_type *bus = get_bus(drv->bus);
	struct device *dev;
	int err = -ENODEV;

	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
	if (dev && dev->driver == drv) {
		device_release_driver(dev);
		err = count;
	}
	put_device(dev);
	put_bus(bus);
	return err;
}

static int ide_replace_subdriver(ide_drive_t *drive, const char *driver)
{
	struct device *dev = &drive->gendev;
	int ret = 1;

	down_write(&dev->bus->subsys.rwsem);
	device_release_driver(dev);
	/* FIXME: device can still be in use by previous driver */
	strlcpy(drive->driver_req, driver, sizeof(drive->driver_req));
	device_attach(dev);
	drive->driver_req[0] = 0;
	if (dev->driver == NULL)
		device_attach(dev);
	if (dev->driver && !strcmp(dev->driver->name, driver))
		ret = 0;
	up_write(&dev->bus->subsys.rwsem);

	return ret;
}

static void brcmf_usb_probe_phase2(struct device *dev, int ret,
				   struct brcmf_fw_request *fwreq)
{
	struct brcmf_bus *bus = dev_get_drvdata(dev);
	struct brcmf_usbdev_info *devinfo = bus->bus_priv.usb->devinfo;
	const struct firmware *fw;

	if (ret)
		goto error;

	brcmf_dbg(USB, "Start fw downloading\n");

	fw = fwreq->items[BRCMF_USB_FW_CODE].binary;
	kfree(fwreq);

	ret = check_file(fw->data);
	if (ret < 0) {
		brcmf_err("invalid firmware\n");
		release_firmware(fw);
		goto error;
	}

	devinfo->image = fw->data;
	devinfo->image_len = fw->size;

	ret = brcmf_usb_fw_download(devinfo);
	release_firmware(fw);
	if (ret)
		goto error;

	/* Attach to the common driver interface */
	ret = brcmf_attach(devinfo->dev, devinfo->settings);
	if (ret)
		goto error;

	complete(&devinfo->dev_init_done);
	return;
error:
	brcmf_dbg(TRACE, "failed: dev=%s, err=%d\n", dev_name(dev), ret);
	complete(&devinfo->dev_init_done);
	device_release_driver(dev);
}

static void acpi_processor_remove(struct acpi_device *device)
{
	struct acpi_processor *pr;

	if (!device || !acpi_driver_data(device))
		return;

	pr = acpi_driver_data(device);
	if (pr->id >= nr_cpu_ids)
		goto out;

	/*
	 * The only reason why we ever get here is CPU hot-removal.  The CPU is
	 * already offline and the ACPI device removal locking prevents it from
	 * being put back online at this point.
	 *
	 * Unbind the driver from the processor device and detach it from the
	 * ACPI companion object.
	 */
	device_release_driver(pr->dev);
	acpi_unbind_one(pr->dev);

	/* Clean up. */
	per_cpu(processor_device_array, pr->id) = NULL;
	per_cpu(processors, pr->id) = NULL;

	cpu_maps_update_begin();
	cpu_hotplug_begin();

	/* Remove the CPU. */
	arch_unregister_cpu(pr->id);
	acpi_unmap_lsapic(pr->id);

	cpu_hotplug_done();
	cpu_maps_update_done();

	try_offline_node(cpu_to_node(pr->id));

 out:
	free_cpumask_var(pr->throttling.shared_cpu_map);
	kfree(pr);
}

static void brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
{
	struct brcmf_fw *fwctx = ctx;
	u32 nvram_length = 0;
	void *nvram = NULL;
	u8 *data = NULL;
	size_t data_len;
	bool raw_nvram;

	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
	if (fw && fw->data) {
		data = (u8 *)fw->data;
		data_len = fw->size;
		raw_nvram = false;
	} else {
		data = bcm47xx_nvram_get_contents(&data_len);
		if (!data && !(fwctx->flags & BRCMF_FW_REQ_NV_OPTIONAL))
			goto fail;
		raw_nvram = true;
	}

	if (data)
		nvram = brcmf_fw_nvram_strip(data, data_len, &nvram_length,
					     fwctx->domain_nr, fwctx->bus_nr);

	if (raw_nvram)
		bcm47xx_nvram_release_contents(data);
	if (fw)
		release_firmware(fw);
	if (!nvram && !(fwctx->flags & BRCMF_FW_REQ_NV_OPTIONAL))
		goto fail;

	fwctx->done(fwctx->dev, fwctx->code, nvram, nvram_length);
	kfree(fwctx);
	return;

fail:
	brcmf_dbg(TRACE, "failed: dev=%s\n", dev_name(fwctx->dev));
	release_firmware(fwctx->code);
	device_release_driver(fwctx->dev);
	kfree(fwctx);
}