// SPDX-License-Identifier: GPL-2.0

  /*
   * driver.c - device id matching, driver model, etc.
   *
   * Copyright 2002 Adam Belay <ambx1@neo.rr.com>

   */

  #include <linux/string.h>
  #include <linux/list.h>
  #include <linux/module.h>
  #include <linux/ctype.h>
  #include <linux/slab.h>

  #include <linux/pnp.h>
  #include "base.h"
  
  static int compare_func(const char *ida, const char *idb)
  {
  	int i;

  	/* we only need to compare the last 4 chars */

  	for (i = 3; i < 7; i++) {

  		if (ida[i] != 'X' &&

  		    idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))

  			return 0;
  	}
  	return 1;
  }
  
  int compare_pnp_id(struct pnp_id *pos, const char *id)
  {
  	if (!pos || !id || (strlen(id) != 7))
  		return 0;

  	if (memcmp(id, "ANYDEVS", 7) == 0)

  		return 1;

  	while (pos) {
  		if (memcmp(pos->id, id, 3) == 0)
  			if (compare_func(pos->id, id) == 1)

  				return 1;
  		pos = pos->next;
  	}
  	return 0;
  }

  static const struct pnp_device_id *match_device(struct pnp_driver *drv,
  						struct pnp_dev *dev)

  {
  	const struct pnp_device_id *drv_id = drv->id_table;

  	if (!drv_id)
  		return NULL;
  
  	while (*drv_id->id) {
  		if (compare_pnp_id(dev->id, drv_id->id))
  			return drv_id;
  		drv_id++;
  	}
  	return NULL;
  }
  
  int pnp_device_attach(struct pnp_dev *pnp_dev)
  {

  	mutex_lock(&pnp_lock);

  	if (pnp_dev->status != PNP_READY) {

  		mutex_unlock(&pnp_lock);

  		return -EBUSY;
  	}
  	pnp_dev->status = PNP_ATTACHED;

  	mutex_unlock(&pnp_lock);

  	return 0;
  }
  
  void pnp_device_detach(struct pnp_dev *pnp_dev)
  {

  	mutex_lock(&pnp_lock);

  	if (pnp_dev->status == PNP_ATTACHED)
  		pnp_dev->status = PNP_READY;

  	mutex_unlock(&pnp_lock);

  }
  
  static int pnp_device_probe(struct device *dev)
  {
  	int error;
  	struct pnp_driver *pnp_drv;
  	struct pnp_dev *pnp_dev;
  	const struct pnp_device_id *dev_id = NULL;
  	pnp_dev = to_pnp_dev(dev);
  	pnp_drv = to_pnp_driver(dev->driver);

  	error = pnp_device_attach(pnp_dev);
  	if (error < 0)
  		return error;
  
  	if (pnp_dev->active == 0) {
  		if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
  			error = pnp_activate_dev(pnp_dev);
  			if (error < 0)
  				return error;
  		}
  	} else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)

  		   == PNP_DRIVER_RES_DISABLE) {

  		error = pnp_disable_dev(pnp_dev);
  		if (error < 0)
  			return error;
  	}
  	error = 0;
  	if (pnp_drv->probe) {
  		dev_id = match_device(pnp_drv, pnp_dev);
  		if (dev_id != NULL)
  			error = pnp_drv->probe(pnp_dev, dev_id);
  	}

  	if (error >= 0) {

  		pnp_dev->driver = pnp_drv;
  		error = 0;
  	} else
  		goto fail;

  	return error;

  fail:

  	pnp_device_detach(pnp_dev);
  	return error;
  }
  
  static int pnp_device_remove(struct device *dev)
  {

  	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
  	struct pnp_driver *drv = pnp_dev->driver;

  
  	if (drv) {
  		if (drv->remove)
  			drv->remove(pnp_dev);
  		pnp_dev->driver = NULL;
  	}

  
  	if (pnp_dev->active &&
  	    (!drv || !(drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)))
  		pnp_disable_dev(pnp_dev);

  	pnp_device_detach(pnp_dev);
  	return 0;
  }

  static void pnp_device_shutdown(struct device *dev)
  {
  	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
  	struct pnp_driver *drv = pnp_dev->driver;
  
  	if (drv && drv->shutdown)
  		drv->shutdown(pnp_dev);
  }

  static int pnp_bus_match(struct device *dev, struct device_driver *drv)
  {

  	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
  	struct pnp_driver *pnp_drv = to_pnp_driver(drv);

  	if (match_device(pnp_drv, pnp_dev) == NULL)
  		return 0;
  	return 1;
  }

  static int __pnp_bus_suspend(struct device *dev, pm_message_t state)

  {

  	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
  	struct pnp_driver *pnp_drv = pnp_dev->driver;

  	int error;
  
  	if (!pnp_drv)
  		return 0;

  	if (pnp_drv->driver.pm && pnp_drv->driver.pm->suspend) {
  		error = pnp_drv->driver.pm->suspend(dev);
  		suspend_report_result(pnp_drv->driver.pm->suspend, error);
  		if (error)
  			return error;
  	}

  	if (pnp_drv->suspend) {
  		error = pnp_drv->suspend(pnp_dev, state);
  		if (error)
  			return error;
  	}

  	if (pnp_can_disable(pnp_dev)) {

  		error = pnp_stop_dev(pnp_dev);
  		if (error)
  			return error;

  	}

  	if (pnp_can_suspend(pnp_dev))

  		pnp_dev->protocol->suspend(pnp_dev, state);

  	return 0;
  }

  static int pnp_bus_suspend(struct device *dev)
  {
  	return __pnp_bus_suspend(dev, PMSG_SUSPEND);
  }
  
  static int pnp_bus_freeze(struct device *dev)
  {
  	return __pnp_bus_suspend(dev, PMSG_FREEZE);
  }

  static int pnp_bus_poweroff(struct device *dev)
  {
  	return __pnp_bus_suspend(dev, PMSG_HIBERNATE);
  }

  static int pnp_bus_resume(struct device *dev)

  {

  	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
  	struct pnp_driver *pnp_drv = pnp_dev->driver;

  	int error;
  
  	if (!pnp_drv)
  		return 0;

  	if (pnp_dev->protocol->resume) {
  		error = pnp_dev->protocol->resume(pnp_dev);
  		if (error)
  			return error;
  	}

  	if (pnp_can_write(pnp_dev)) {

  		error = pnp_start_dev(pnp_dev);
  		if (error)
  			return error;
  	}

  	if (pnp_drv->driver.pm && pnp_drv->driver.pm->resume) {
  		error = pnp_drv->driver.pm->resume(dev);
  		if (error)
  			return error;
  	}

  	if (pnp_drv->resume) {
  		error = pnp_drv->resume(pnp_dev);
  		if (error)
  			return error;
  	}

  
  	return 0;

  }

  static const struct dev_pm_ops pnp_bus_dev_pm_ops = {

  	/* Suspend callbacks */

  	.suspend = pnp_bus_suspend,

  	.resume = pnp_bus_resume,

  	/* Hibernate callbacks */
  	.freeze = pnp_bus_freeze,
  	.thaw = pnp_bus_resume,
  	.poweroff = pnp_bus_poweroff,
  	.restore = pnp_bus_resume,

  };

  struct bus_type pnp_bus_type = {

  	.name    = "pnp",
  	.match   = pnp_bus_match,
  	.probe   = pnp_device_probe,
  	.remove  = pnp_device_remove,

  	.shutdown = pnp_device_shutdown,

  	.pm	 = &pnp_bus_dev_pm_ops,

  	.dev_groups = pnp_dev_groups,

  };

  int pnp_register_driver(struct pnp_driver *drv)
  {

  	drv->driver.name = drv->name;
  	drv->driver.bus = &pnp_bus_type;

  	return driver_register(&drv->driver);

  }
  
  void pnp_unregister_driver(struct pnp_driver *drv)
  {
  	driver_unregister(&drv->driver);

  }
  
  /**
   * pnp_add_id - adds an EISA id to the specified device

   * @dev: pointer to the desired device

   * @id: pointer to an EISA id string

   */

  struct pnp_id *pnp_add_id(struct pnp_dev *dev, const char *id)

  {

  	struct pnp_id *dev_id, *ptr;

  	dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
  	if (!dev_id)
  		return NULL;
  
  	dev_id->id[0] = id[0];
  	dev_id->id[1] = id[1];
  	dev_id->id[2] = id[2];
  	dev_id->id[3] = tolower(id[3]);
  	dev_id->id[4] = tolower(id[4]);
  	dev_id->id[5] = tolower(id[5]);
  	dev_id->id[6] = tolower(id[6]);
  	dev_id->id[7] = '\0';
  
  	dev_id->next = NULL;

  	ptr = dev->id;
  	while (ptr && ptr->next)
  		ptr = ptr->next;
  	if (ptr)

  		ptr->next = dev_id;

  	else

  		dev->id = dev_id;
  
  	return dev_id;

  }
  
  EXPORT_SYMBOL(pnp_register_driver);
  EXPORT_SYMBOL(pnp_unregister_driver);

  EXPORT_SYMBOL(pnp_device_attach);
  EXPORT_SYMBOL(pnp_device_detach);