text: /*
   * Copyright (C) 2005, 2006 IBM Corporation
   * Copyright (C) 2014, 2015 Intel Corporation
   *
   * Authors:
   * Leendert van Doorn <leendert@watson.ibm.com>
   * Kylene Hall <kjhall@us.ibm.com>
   *
   * Maintained by: <tpmdd-devel@lists.sourceforge.net>
   *
   * Device driver for TCG/TCPA TPM (trusted platform module).
   * Specifications at www.trustedcomputinggroup.org
   *
   * This device driver implements the TPM interface as defined in
   * the TCG TPM Interface Spec version 1.2, revision 1.0.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as
   * published by the Free Software Foundation, version 2 of the
   * License.
   */
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/moduleparam.h>
  #include <linux/pnp.h>
  #include <linux/slab.h>
  #include <linux/interrupt.h>
  #include <linux/wait.h>
  #include <linux/acpi.h>
  #include <linux/freezer.h>
  #include "tpm.h"
  #include "tpm_tis_core.h"
  
  struct tpm_info {
  	struct resource res;
  	/* irq > 0 means: use irq $irq;
  	 * irq = 0 means: autoprobe for an irq;
  	 * irq = -1 means: no irq support
  	 */
  	int irq;
  };
  
  struct tpm_tis_tcg_phy {
  	struct tpm_tis_data priv;
  	void __iomem *iobase;
  };
  
  static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
  {
  	return container_of(data, struct tpm_tis_tcg_phy, priv);
  }
  
  static bool interrupts = true;
  module_param(interrupts, bool, 0444);
  MODULE_PARM_DESC(interrupts, "Enable interrupts");
  
  static bool itpm;
  module_param(itpm, bool, 0444);
  MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
  
  static bool force;
  #ifdef CONFIG_X86
  module_param(force, bool, 0444);
  MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
  #endif
  
  #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
  static int has_hid(struct acpi_device *dev, const char *hid)
  {
  	struct acpi_hardware_id *id;
  
  	list_for_each_entry(id, &dev->pnp.ids, list)
  		if (!strcmp(hid, id->id))
  			return 1;
  
  	return 0;
  }
  
  static inline int is_itpm(struct acpi_device *dev)
  {
  	return has_hid(dev, "INTC0102");
  }
  #else
  static inline int is_itpm(struct acpi_device *dev)
  {
  	return 0;
  }
  #endif
  
  static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
  			      u8 *result)
  {
  	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
  
  	while (len--)
  		*result++ = ioread8(phy->iobase + addr);
  	return 0;
  }
  
  static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
  			       const u8 *value)
  {
  	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
  
  	while (len--)
  		iowrite8(*value++, phy->iobase + addr);
  	return 0;
  }
  
  static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
  {
  	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
  
  	*result = ioread16(phy->iobase + addr);
  	return 0;
  }
  
  static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
  {
  	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
  
  	*result = ioread32(phy->iobase + addr);
  	return 0;
  }
  
  static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
  {
  	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
  
  	iowrite32(value, phy->iobase + addr);
  	return 0;
  }
  
  static const struct tpm_tis_phy_ops tpm_tcg = {
  	.read_bytes = tpm_tcg_read_bytes,
  	.write_bytes = tpm_tcg_write_bytes,
  	.read16 = tpm_tcg_read16,
  	.read32 = tpm_tcg_read32,
  	.write32 = tpm_tcg_write32,
  };
  
  static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
  			acpi_handle acpi_dev_handle)
  {
  	struct tpm_tis_tcg_phy *phy;
  	int irq = -1;
  
  	phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
  	if (phy == NULL)
  		return -ENOMEM;
  
  	phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
  	if (IS_ERR(phy->iobase))
  		return PTR_ERR(phy->iobase);
  
  	if (interrupts)
  		irq = tpm_info->irq;
  
  	if (itpm)
  		phy->priv.flags |= TPM_TIS_ITPM_POSSIBLE;
  
  	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
  				 acpi_dev_handle);
  }
  
  static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
  
  static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
  			    const struct pnp_device_id *pnp_id)
  {
  	struct tpm_info tpm_info = {};
  	acpi_handle acpi_dev_handle = NULL;
  	struct resource *res;
  
  	res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
  	if (!res)
  		return -ENODEV;
  	tpm_info.res = *res;
  
  	if (pnp_irq_valid(pnp_dev, 0))
  		tpm_info.irq = pnp_irq(pnp_dev, 0);
  	else
  		tpm_info.irq = -1;
  
  	if (pnp_acpi_device(pnp_dev)) {
  		if (is_itpm(pnp_acpi_device(pnp_dev)))
  			itpm = true;
  
  		acpi_dev_handle = ACPI_HANDLE(&pnp_dev->dev);
  	}
  
  	return tpm_tis_init(&pnp_dev->dev, &tpm_info, acpi_dev_handle);
  }
  
  static struct pnp_device_id tpm_pnp_tbl[] = {
  	{"PNP0C31", 0},		/* TPM */
  	{"ATM1200", 0},		/* Atmel */
  	{"IFX0102", 0},		/* Infineon */
  	{"BCM0101", 0},		/* Broadcom */
  	{"BCM0102", 0},		/* Broadcom */
  	{"NSC1200", 0},		/* National */
  	{"ICO0102", 0},		/* Intel */
  	/* Add new here */
  	{"", 0},		/* User Specified */
  	{"", 0}			/* Terminator */
  };
  MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
  
  static void tpm_tis_pnp_remove(struct pnp_dev *dev)
  {
  	struct tpm_chip *chip = pnp_get_drvdata(dev);
  
  	tpm_chip_unregister(chip);
  	tpm_tis_remove(chip);
  }
  
  static struct pnp_driver tis_pnp_driver = {
  	.name = "tpm_tis",
  	.id_table = tpm_pnp_tbl,
  	.probe = tpm_tis_pnp_init,
  	.remove = tpm_tis_pnp_remove,
  	.driver	= {
  		.pm = &tpm_tis_pm,
  	},
  };
  
  #define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
  module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
  		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
  MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
  
  #ifdef CONFIG_ACPI
  static int tpm_check_resource(struct acpi_resource *ares, void *data)
  {
  	struct tpm_info *tpm_info = (struct tpm_info *) data;
  	struct resource res;
  
  	if (acpi_dev_resource_interrupt(ares, 0, &res))
  		tpm_info->irq = res.start;
  	else if (acpi_dev_resource_memory(ares, &res)) {
  		tpm_info->res = res;
  		tpm_info->res.name = NULL;
  	}
  
  	return 1;
  }
  
  static int tpm_tis_acpi_init(struct acpi_device *acpi_dev)
  {
  	struct acpi_table_tpm2 *tbl;
  	acpi_status st;
  	struct list_head resources;
  	struct tpm_info tpm_info = {};
  	int ret;
  
  	st = acpi_get_table(ACPI_SIG_TPM2, 1,
  			    (struct acpi_table_header **) &tbl);
  	if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
  		dev_err(&acpi_dev->dev,
  			FW_BUG "failed to get TPM2 ACPI table\n");
  		return -EINVAL;
  	}
  
  	if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
  		return -ENODEV;
  
  	INIT_LIST_HEAD(&resources);
  	tpm_info.irq = -1;
  	ret = acpi_dev_get_resources(acpi_dev, &resources, tpm_check_resource,
  				     &tpm_info);
  	if (ret < 0)
  		return ret;
  
  	acpi_dev_free_resource_list(&resources);
  
  	if (resource_type(&tpm_info.res) != IORESOURCE_MEM) {
  		dev_err(&acpi_dev->dev,
  			FW_BUG "TPM2 ACPI table does not define a memory resource\n");
  		return -EINVAL;
  	}
  
  	if (is_itpm(acpi_dev))
  		itpm = true;
  
  	return tpm_tis_init(&acpi_dev->dev, &tpm_info, acpi_dev->handle);
  }
  
  static int tpm_tis_acpi_remove(struct acpi_device *dev)
  {
  	struct tpm_chip *chip = dev_get_drvdata(&dev->dev);
  
  	tpm_chip_unregister(chip);
  	tpm_tis_remove(chip);
  
  	return 0;
  }
  
  static struct acpi_device_id tpm_acpi_tbl[] = {
  	{"MSFT0101", 0},	/* TPM 2.0 */
  	/* Add new here */
  	{"", 0},		/* User Specified */
  	{"", 0}			/* Terminator */
  };
  MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
  
  static struct acpi_driver tis_acpi_driver = {
  	.name = "tpm_tis",
  	.ids = tpm_acpi_tbl,
  	.ops = {
  		.add = tpm_tis_acpi_init,
  		.remove = tpm_tis_acpi_remove,
  	},
  	.drv = {
  		.pm = &tpm_tis_pm,
  	},
  };
  #endif
  
  static struct platform_device *force_pdev;
  
  static int tpm_tis_plat_probe(struct platform_device *pdev)
  {
  	struct tpm_info tpm_info = {};
  	struct resource *res;
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (res == NULL) {
  		dev_err(&pdev->dev, "no memory resource defined\n");
  		return -ENODEV;
  	}
  	tpm_info.res = *res;
  
  	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
  	if (res) {
  		tpm_info.irq = res->start;
  	} else {
  		if (pdev == force_pdev)
  			tpm_info.irq = -1;
  		else
  			/* When forcing auto probe the IRQ */
  			tpm_info.irq = 0;
  	}
  
  	return tpm_tis_init(&pdev->dev, &tpm_info, NULL);
  }
  
  static int tpm_tis_plat_remove(struct platform_device *pdev)
  {
  	struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
  
  	tpm_chip_unregister(chip);
  	tpm_tis_remove(chip);
  
  	return 0;
  }
  
  static struct platform_driver tis_drv = {
  	.probe = tpm_tis_plat_probe,
  	.remove = tpm_tis_plat_remove,
  	.driver = {
  		.name		= "tpm_tis",
  		.pm		= &tpm_tis_pm,
  	},
  };
  
  static int tpm_tis_force_device(void)
  {
  	struct platform_device *pdev;
  	static const struct resource x86_resources[] = {
  		{
  			.start = 0xFED40000,
  			.end = 0xFED40000 + TIS_MEM_LEN - 1,
  			.flags = IORESOURCE_MEM,
  		},
  	};
  
  	if (!force)
  		return 0;
  
  	/* The driver core will match the name tpm_tis of the device to
  	 * the tpm_tis platform driver and complete the setup via
  	 * tpm_tis_plat_probe
  	 */
  	pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
  					       ARRAY_SIZE(x86_resources));
  	if (IS_ERR(pdev))
  		return PTR_ERR(pdev);
  	force_pdev = pdev;
  
  	return 0;
  }
  
  static int __init init_tis(void)
  {
  	int rc;
  
  	rc = tpm_tis_force_device();
  	if (rc)
  		goto err_force;
  
  	rc = platform_driver_register(&tis_drv);
  	if (rc)
  		goto err_platform;
  
  #ifdef CONFIG_ACPI
  	rc = acpi_bus_register_driver(&tis_acpi_driver);
  	if (rc)
  		goto err_acpi;
  #endif
  
  	if (IS_ENABLED(CONFIG_PNP)) {
  		rc = pnp_register_driver(&tis_pnp_driver);
  		if (rc)
  			goto err_pnp;
  	}
  
  	return 0;
  
  err_pnp:
  #ifdef CONFIG_ACPI
  	acpi_bus_unregister_driver(&tis_acpi_driver);
  err_acpi:
  #endif
  	platform_driver_unregister(&tis_drv);
  err_platform:
  	if (force_pdev)
  		platform_device_unregister(force_pdev);
  err_force:
  	return rc;
  }
  
  static void __exit cleanup_tis(void)
  {
  	pnp_unregister_driver(&tis_pnp_driver);
  #ifdef CONFIG_ACPI
  	acpi_bus_unregister_driver(&tis_acpi_driver);
  #endif
  	platform_driver_unregister(&tis_drv);
  
  	if (force_pdev)
  		platform_device_unregister(force_pdev);
  }
  
  module_init(init_tis);
  module_exit(cleanup_tis);
  MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
  MODULE_DESCRIPTION("TPM Driver");
  MODULE_VERSION("2.0");
  MODULE_LICENSE("GPL");
  