v4.19.13 snapshot.
diff --git a/drivers/misc/mei/pci-txe.c b/drivers/misc/mei/pci-txe.c
new file mode 100644
index 0000000..e1b9091
--- /dev/null
+++ b/drivers/misc/mei/pci-txe.c
@@ -0,0 +1,422 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2013-2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/uuid.h>
+#include <linux/jiffies.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+
+#include "mei_dev.h"
+#include "hw-txe.h"
+
+static const struct pci_device_id mei_txe_pci_tbl[] = {
+	{PCI_VDEVICE(INTEL, 0x0F18)}, /* Baytrail */
+	{PCI_VDEVICE(INTEL, 0x2298)}, /* Cherrytrail */
+
+	{0, }
+};
+MODULE_DEVICE_TABLE(pci, mei_txe_pci_tbl);
+
+#ifdef CONFIG_PM
+static inline void mei_txe_set_pm_domain(struct mei_device *dev);
+static inline void mei_txe_unset_pm_domain(struct mei_device *dev);
+#else
+static inline void mei_txe_set_pm_domain(struct mei_device *dev) {}
+static inline void mei_txe_unset_pm_domain(struct mei_device *dev) {}
+#endif /* CONFIG_PM */
+
+/**
+ * mei_txe_probe - Device Initialization Routine
+ *
+ * @pdev: PCI device structure
+ * @ent: entry in mei_txe_pci_tbl
+ *
+ * Return: 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;
+	const int mask = BIT(SEC_BAR) | BIT(BRIDGE_BAR);
+	int err;
+
+	/* enable pci dev */
+	err = pcim_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 and mapping IO device memory for mei driver */
+	err = pcim_iomap_regions(pdev, mask, KBUILD_MODNAME);
+	if (err) {
+		dev_err(&pdev->dev, "failed to get pci regions.\n");
+		goto end;
+	}
+
+	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 end;
+		}
+	}
+
+	/* allocates and initializes the mei dev structure */
+	dev = mei_txe_dev_init(pdev);
+	if (!dev) {
+		err = -ENOMEM;
+		goto end;
+	}
+	hw = to_txe_hw(dev);
+	hw->mem_addr = pcim_iomap_table(pdev);
+
+	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 end;
+	}
+
+	if (mei_start(dev)) {
+		dev_err(&pdev->dev, "init hw failure.\n");
+		err = -ENODEV;
+		goto release_irq;
+	}
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+
+	err = mei_register(dev, &pdev->dev);
+	if (err)
+		goto stop;
+
+	pci_set_drvdata(pdev, dev);
+
+	/*
+	 * MEI requires to resume from runtime suspend mode
+	 * in order to perform link reset flow upon system suspend.
+	 */
+	dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NEVER_SKIP);
+
+	/*
+	 * TXE maps runtime suspend/resume to own power gating states,
+	 * hence we need to go around native PCI runtime service which
+	 * eventually brings the device into D3cold/hot state.
+	 * But the TXE device cannot wake up from D3 unlike from own
+	 * power gating. To get around PCI device native runtime pm,
+	 * TXE uses runtime pm domain handlers which take precedence.
+	 */
+	mei_txe_set_pm_domain(dev);
+
+	pm_runtime_put_noidle(&pdev->dev);
+
+	return 0;
+
+stop:
+	mei_stop(dev);
+release_irq:
+	mei_cancel_work(dev);
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+end:
+	dev_err(&pdev->dev, "initialization failed.\n");
+	return err;
+}
+
+/**
+ * mei_txe_remove - Device Shutdown Routine
+ *
+ * @pdev: PCI device structure
+ *
+ *  mei_txe_shutdown is called from the reboot notifier
+ *  it's a simplified version of remove so we go down
+ *  faster.
+ */
+static void mei_txe_shutdown(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return;
+
+	dev_dbg(&pdev->dev, "shutdown\n");
+	mei_stop(dev);
+
+	mei_txe_unset_pm_domain(dev);
+
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+}
+
+/**
+ * mei_txe_remove - Device Removal Routine
+ *
+ * @pdev: PCI device structure
+ *
+ * mei_remove is called by the PCI subsystem to alert the driver
+ * that it should release a PCI device.
+ */
+static void mei_txe_remove(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev) {
+		dev_err(&pdev->dev, "mei: dev == NULL\n");
+		return;
+	}
+
+	pm_runtime_get_noresume(&pdev->dev);
+
+	mei_stop(dev);
+
+	mei_txe_unset_pm_domain(dev);
+
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+
+	mei_deregister(dev);
+}
+
+
+#ifdef CONFIG_PM_SLEEP
+static int mei_txe_pci_suspend(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev = pci_get_drvdata(pdev);
+
+	if (!dev)
+		return -ENODEV;
+
+	dev_dbg(&pdev->dev, "suspend\n");
+
+	mei_stop(dev);
+
+	mei_disable_interrupts(dev);
+
+	free_irq(pdev->irq, dev);
+	pci_disable_msi(pdev);
+
+	return 0;
+}
+
+static int mei_txe_pci_resume(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	int err;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	pci_enable_msi(pdev);
+
+	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, "request_threaded_irq failed: irq = %d.\n",
+				pdev->irq);
+		return err;
+	}
+
+	err = mei_restart(dev);
+
+	return err;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int mei_txe_pm_runtime_idle(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+
+	dev_dbg(&pdev->dev, "rpm: txe: runtime_idle\n");
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+	if (mei_write_is_idle(dev))
+		pm_runtime_autosuspend(device);
+
+	return -EBUSY;
+}
+static int mei_txe_pm_runtime_suspend(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(&pdev->dev, "rpm: txe: runtime suspend\n");
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (mei_write_is_idle(dev))
+		ret = mei_txe_aliveness_set_sync(dev, 0);
+	else
+		ret = -EAGAIN;
+
+	/* keep irq on we are staying in D0 */
+
+	dev_dbg(&pdev->dev, "rpm: txe: runtime suspend ret=%d\n", ret);
+
+	mutex_unlock(&dev->device_lock);
+
+	if (ret && ret != -EAGAIN)
+		schedule_work(&dev->reset_work);
+
+	return ret;
+}
+
+static int mei_txe_pm_runtime_resume(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(&pdev->dev, "rpm: txe: runtime resume\n");
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	mei_enable_interrupts(dev);
+
+	ret = mei_txe_aliveness_set_sync(dev, 1);
+
+	mutex_unlock(&dev->device_lock);
+
+	dev_dbg(&pdev->dev, "rpm: txe: runtime resume ret = %d\n", ret);
+
+	if (ret)
+		schedule_work(&dev->reset_work);
+
+	return ret;
+}
+
+/**
+ * mei_txe_set_pm_domain - fill and set pm domain structure for device
+ *
+ * @dev: mei_device
+ */
+static inline void mei_txe_set_pm_domain(struct mei_device *dev)
+{
+	struct pci_dev *pdev  = to_pci_dev(dev->dev);
+
+	if (pdev->dev.bus && pdev->dev.bus->pm) {
+		dev->pg_domain.ops = *pdev->dev.bus->pm;
+
+		dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
+		dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
+		dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
+
+		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
+	}
+}
+
+/**
+ * mei_txe_unset_pm_domain - clean pm domain structure for device
+ *
+ * @dev: mei_device
+ */
+static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
+{
+	/* stop using pm callbacks if any */
+	dev_pm_domain_set(dev->dev, NULL);
+}
+
+static const struct dev_pm_ops mei_txe_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
+				mei_txe_pci_resume)
+	SET_RUNTIME_PM_OPS(
+		mei_txe_pm_runtime_suspend,
+		mei_txe_pm_runtime_resume,
+		mei_txe_pm_runtime_idle)
+};
+
+#define MEI_TXE_PM_OPS	(&mei_txe_pm_ops)
+#else
+#define MEI_TXE_PM_OPS	NULL
+#endif /* CONFIG_PM */
+
+/*
+ *  PCI driver structure
+ */
+static struct pci_driver mei_txe_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = mei_txe_pci_tbl,
+	.probe = mei_txe_probe,
+	.remove = mei_txe_remove,
+	.shutdown = mei_txe_shutdown,
+	.driver.pm = MEI_TXE_PM_OPS,
+};
+
+module_pci_driver(mei_txe_driver);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
+MODULE_LICENSE("GPL v2");