text: // SPDX-License-Identifier: GPL-2.0+
  /*
   * PCI Express Hot Plug Controller Driver
   *
   * Copyright (C) 1995,2001 Compaq Computer Corporation
   * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   * Copyright (C) 2001 IBM Corp.
   * Copyright (C) 2003-2004 Intel Corporation
   *
   * All rights reserved.
   *
   * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
   *
   * Authors:
   *   Dan Zink <dan.zink@compaq.com>
   *   Greg Kroah-Hartman <greg@kroah.com>
   *   Dely Sy <dely.l.sy@intel.com>"
   */
  
  #include <linux/moduleparam.h>
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/types.h>
  #include <linux/pci.h>
  #include "pciehp.h"
  #include <linux/interrupt.h>
  #include <linux/time.h>
  
  /* Global variables */
  bool pciehp_debug;
  bool pciehp_poll_mode;
  int pciehp_poll_time;
  static bool pciehp_force;
  
  /*
   * not really modular, but the easiest way to keep compat with existing
   * bootargs behaviour is to continue using module_param here.
   */
  module_param(pciehp_debug, bool, 0644);
  module_param(pciehp_poll_mode, bool, 0644);
  module_param(pciehp_poll_time, int, 0644);
  module_param(pciehp_force, bool, 0644);
  MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
  MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
  MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
  MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if OSHP is missing");
  
  #define PCIE_MODULE_NAME "pciehp"
  
  static int set_attention_status(struct hotplug_slot *slot, u8 value);
  static int enable_slot(struct hotplug_slot *slot);
  static int disable_slot(struct hotplug_slot *slot);
  static int get_power_status(struct hotplug_slot *slot, u8 *value);
  static int get_attention_status(struct hotplug_slot *slot, u8 *value);
  static int get_latch_status(struct hotplug_slot *slot, u8 *value);
  static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
  static int reset_slot(struct hotplug_slot *slot, int probe);
  
  /**
   * release_slot - free up the memory used by a slot
   * @hotplug_slot: slot to free
   */
  static void release_slot(struct hotplug_slot *hotplug_slot)
  {
  	kfree(hotplug_slot->ops);
  	kfree(hotplug_slot->info);
  	kfree(hotplug_slot);
  }
  
  static int init_slot(struct controller *ctrl)
  {
  	struct slot *slot = ctrl->slot;
  	struct hotplug_slot *hotplug = NULL;
  	struct hotplug_slot_info *info = NULL;
  	struct hotplug_slot_ops *ops = NULL;
  	char name[SLOT_NAME_SIZE];
  	int retval = -ENOMEM;
  
  	hotplug = kzalloc(sizeof(*hotplug), GFP_KERNEL);
  	if (!hotplug)
  		goto out;
  
  	info = kzalloc(sizeof(*info), GFP_KERNEL);
  	if (!info)
  		goto out;
  
  	/* Setup hotplug slot ops */
  	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
  	if (!ops)
  		goto out;
  
  	ops->enable_slot = enable_slot;
  	ops->disable_slot = disable_slot;
  	ops->get_power_status = get_power_status;
  	ops->get_adapter_status = get_adapter_status;
  	ops->reset_slot = reset_slot;
  	if (MRL_SENS(ctrl))
  		ops->get_latch_status = get_latch_status;
  	if (ATTN_LED(ctrl)) {
  		ops->get_attention_status = get_attention_status;
  		ops->set_attention_status = set_attention_status;
  	} else if (ctrl->pcie->port->hotplug_user_indicators) {
  		ops->get_attention_status = pciehp_get_raw_indicator_status;
  		ops->set_attention_status = pciehp_set_raw_indicator_status;
  	}
  
  	/* register this slot with the hotplug pci core */
  	hotplug->info = info;
  	hotplug->private = slot;
  	hotplug->release = &release_slot;
  	hotplug->ops = ops;
  	slot->hotplug_slot = hotplug;
  	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
  
  	retval = pci_hp_register(hotplug,
  				 ctrl->pcie->port->subordinate, 0, name);
  	if (retval)
  		ctrl_err(ctrl, "pci_hp_register failed: error %d\n", retval);
  out:
  	if (retval) {
  		kfree(ops);
  		kfree(info);
  		kfree(hotplug);
  	}
  	return retval;
  }
  
  static void cleanup_slot(struct controller *ctrl)
  {
  	pci_hp_deregister(ctrl->slot->hotplug_slot);
  }
  
  /*
   * set_attention_status - Turns the Amber LED for a slot on, off or blink
   */
  static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	pciehp_set_attention_status(slot, status);
  	return 0;
  }
  
  
  static int enable_slot(struct hotplug_slot *hotplug_slot)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	return pciehp_sysfs_enable_slot(slot);
  }
  
  
  static int disable_slot(struct hotplug_slot *hotplug_slot)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	return pciehp_sysfs_disable_slot(slot);
  }
  
  static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	pciehp_get_power_status(slot, value);
  	return 0;
  }
  
  static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	pciehp_get_attention_status(slot, value);
  	return 0;
  }
  
  static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	pciehp_get_latch_status(slot, value);
  	return 0;
  }
  
  static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	pciehp_get_adapter_status(slot, value);
  	return 0;
  }
  
  static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
  {
  	struct slot *slot = hotplug_slot->private;
  
  	return pciehp_reset_slot(slot, probe);
  }
  
  static int pciehp_probe(struct pcie_device *dev)
  {
  	int rc;
  	struct controller *ctrl;
  	struct slot *slot;
  	u8 occupied, poweron;
  
  	/* If this is not a "hotplug" service, we have no business here. */
  	if (dev->service != PCIE_PORT_SERVICE_HP)
  		return -ENODEV;
  
  	if (!dev->port->subordinate) {
  		/* Can happen if we run out of bus numbers during probe */
  		dev_err(&dev->device,
  			"Hotplug bridge without secondary bus, ignoring\n");
  		return -ENODEV;
  	}
  
  	ctrl = pcie_init(dev);
  	if (!ctrl) {
  		dev_err(&dev->device, "Controller initialization failed\n");
  		return -ENODEV;
  	}
  	set_service_data(dev, ctrl);
  
  	/* Setup the slot information structures */
  	rc = init_slot(ctrl);
  	if (rc) {
  		if (rc == -EBUSY)
  			ctrl_warn(ctrl, "Slot already registered by another hotplug driver\n");
  		else
  			ctrl_err(ctrl, "Slot initialization failed (%d)\n", rc);
  		goto err_out_release_ctlr;
  	}
  
  	/* Enable events after we have setup the data structures */
  	rc = pcie_init_notification(ctrl);
  	if (rc) {
  		ctrl_err(ctrl, "Notification initialization failed (%d)\n", rc);
  		goto err_out_free_ctrl_slot;
  	}
  
  	/* Check if slot is occupied */
  	slot = ctrl->slot;
  	pciehp_get_adapter_status(slot, &occupied);
  	pciehp_get_power_status(slot, &poweron);
  	if (occupied && pciehp_force) {
  		mutex_lock(&slot->hotplug_lock);
  		pciehp_enable_slot(slot);
  		mutex_unlock(&slot->hotplug_lock);
  	}
  	/* If empty slot's power status is on, turn power off */
  	if (!occupied && poweron && POWER_CTRL(ctrl))
  		pciehp_power_off_slot(slot);
  
  	return 0;
  
  err_out_free_ctrl_slot:
  	cleanup_slot(ctrl);
  err_out_release_ctlr:
  	pciehp_release_ctrl(ctrl);
  	return -ENODEV;
  }
  
  static void pciehp_remove(struct pcie_device *dev)
  {
  	struct controller *ctrl = get_service_data(dev);
  
  	cleanup_slot(ctrl);
  	pciehp_release_ctrl(ctrl);
  }
  
  #ifdef CONFIG_PM
  static int pciehp_suspend(struct pcie_device *dev)
  {
  	return 0;
  }
  
  static int pciehp_resume(struct pcie_device *dev)
  {
  	struct controller *ctrl;
  	struct slot *slot;
  	u8 status;
  
  	ctrl = get_service_data(dev);
  
  	/* reinitialize the chipset's event detection logic */
  	pcie_reenable_notification(ctrl);
  
  	slot = ctrl->slot;
  
  	/* Check if slot is occupied */
  	pciehp_get_adapter_status(slot, &status);
  	mutex_lock(&slot->hotplug_lock);
  	if (status)
  		pciehp_enable_slot(slot);
  	else
  		pciehp_disable_slot(slot);
  	mutex_unlock(&slot->hotplug_lock);
  	return 0;
  }
  #endif /* PM */
  
  static struct pcie_port_service_driver hpdriver_portdrv = {
  	.name		= PCIE_MODULE_NAME,
  	.port_type	= PCIE_ANY_PORT,
  	.service	= PCIE_PORT_SERVICE_HP,
  
  	.probe		= pciehp_probe,
  	.remove		= pciehp_remove,
  
  #ifdef	CONFIG_PM
  	.suspend	= pciehp_suspend,
  	.resume		= pciehp_resume,
  #endif	/* PM */
  };
  
  static int __init pcied_init(void)
  {
  	int retval = 0;
  
  	retval = pcie_port_service_register(&hpdriver_portdrv);
  	dbg("pcie_port_service_register = %d\n", retval);
  	if (retval)
  		dbg("Failure to register service\n");
  
  	return retval;
  }
  device_initcall(pcied_init);
  