int mei_txe_dma_setup(struct mei_device *dev)
{
	struct mei_txe_hw *hw = to_txe_hw(dev);
	int err;

	err = mei_reserver_dma_acpi(dev);
	if (err)
		err = mei_alloc_dma(dev);

	if (err)
		return err;

	err = mei_txe_setup_satt2(dev,
		dma_to_phys(&dev->pdev->dev, hw->pool_paddr), hw->pool_size);

	if (err) {
		if (hw->pool_release)
			hw->pool_release(hw);
		return err;
	}

	hw->mdev = mei_mm_init(&dev->pdev->dev,
		hw->pool_vaddr, hw->pool_paddr, hw->pool_size);

	if (IS_ERR_OR_NULL(hw->mdev))
		return PTR_ERR(hw->mdev);

	return 0;
}
/**
 * mei_probe - Device Initialization Routine
 *
 * @pdev: PCI device structure
 * @ent: entry in mei_txe_pci_tbl
 *
 * returns 0 on success, <0 on failure.
 */
static int mei_txe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
    struct mei_device *dev;
    struct mei_txe_hw *hw;
    int err;
    int i;

    /* enable pci dev */
    err = pci_enable_device(pdev);
    if (err) {
        dev_err(&pdev->dev, "failed to enable pci device.\n");
        goto end;
    }
    /* set PCI host mastering  */
    pci_set_master(pdev);
    /* pci request regions for mei driver */
    err = pci_request_regions(pdev, KBUILD_MODNAME);
    if (err) {
        dev_err(&pdev->dev, "failed to get pci regions.\n");
        goto disable_device;
    }

    err = pci_set_dma_mask(pdev, DMA_BIT_MASK(36));
    if (err) {
        err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
        if (err) {
            dev_err(&pdev->dev, "No suitable DMA available.\n");
            goto release_regions;
        }
    }

    /* allocates and initializes the mei dev structure */
    dev = mei_txe_dev_init(pdev);
    if (!dev) {
        err = -ENOMEM;
        goto release_regions;
    }
    hw = to_txe_hw(dev);


    err = mei_reserver_dma_acpi(dev);
    if (err)
        err = mei_alloc_dma(dev);
    if (err)
        goto free_device;

    /* mapping  IO device memory */
    for (i = SEC_BAR; i < NUM_OF_MEM_BARS; i++) {
        hw->mem_addr[i] = pci_iomap(pdev, i, 0);
        if (!hw->mem_addr[i]) {
            dev_err(&pdev->dev, "mapping I/O device memory failure.\n");
            err = -ENOMEM;
            goto free_device;
        }
    }


    pci_enable_msi(pdev);

    /* clear spurious interrupts */
    mei_clear_interrupts(dev);

    /* request and enable interrupt  */
    if (pci_dev_msi_enabled(pdev))
        err = request_threaded_irq(pdev->irq,
                                   NULL,
                                   mei_txe_irq_thread_handler,
                                   IRQF_ONESHOT, KBUILD_MODNAME, dev);
    else
        err = request_threaded_irq(pdev->irq,
                                   mei_txe_irq_quick_handler,
                                   mei_txe_irq_thread_handler,
                                   IRQF_SHARED, KBUILD_MODNAME, dev);
    if (err) {
        dev_err(&pdev->dev, "mei: request_threaded_irq failure. irq = %d\n",
                pdev->irq);
        goto free_device;
    }

    if (mei_start(dev)) {
        dev_err(&pdev->dev, "init hw failure.\n");
        err = -ENODEV;
        goto release_irq;
    }

    err = mei_txe_setup_satt2(dev,
                              dma_to_phys(&dev->pdev->dev, hw->pool_paddr), hw->pool_size);
    if (err)
        goto release_irq;


    err = mei_register(dev);
    if (err)
        goto release_irq;

    pci_set_drvdata(pdev, dev);

    hw->mdev = mei_mm_init(&dev->pdev->dev,
                           hw->pool_vaddr, hw->pool_paddr, hw->pool_size);

    if (IS_ERR_OR_NULL(hw->mdev))
        goto deregister_mei;

    pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT);
    pm_runtime_use_autosuspend(&pdev->dev);

    pm_runtime_mark_last_busy(&pdev->dev);

    /*
    * For not wake-able HW runtime pm framework
    * can't be used on pci device level.
    * Use domain runtime pm callbacks instead.
    */
    if (!pci_dev_run_wake(pdev))
        mei_txe_set_pm_domain(dev);

    pm_runtime_put_noidle(&pdev->dev);

    if (!nopg)
        pm_runtime_allow(&pdev->dev);

    return 0;

deregister_mei:
    mei_deregister(dev);
release_irq:

    mei_cancel_work(dev);

    /* disable interrupts */
    mei_disable_interrupts(dev);

    free_irq(pdev->irq, dev);
    pci_disable_msi(pdev);

free_device:
    if (hw->pool_release)
        hw->pool_release(hw);

    mei_txe_pci_iounmap(pdev, hw);

    kfree(dev);
release_regions:
    pci_release_regions(pdev);
disable_device:
    pci_disable_device(pdev);
end:
    dev_err(&pdev->dev, "initialization failed.\n");
    return err;
}