text: /*
   * Copyright (C) 2012 Thomas Petazzoni
   *
   * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   *
   * This file is licensed under the terms of the GNU General Public
   * License version 2.  This program is licensed "as is" without any
   * warranty of any kind, whether express or implied.
   */
  
  #include <linux/acpi.h>
  #include <linux/init.h>
  #include <linux/of_device.h>
  #include <linux/of_irq.h>
  #include <linux/irqchip.h>
  #include <linux/platform_device.h>
  
  /*
   * This special of_device_id is the sentinel at the end of the
   * of_device_id[] array of all irqchips. It is automatically placed at
   * the end of the array by the linker, thanks to being part of a
   * special section.
   */
  static const struct of_device_id
  irqchip_of_match_end __used __section("__irqchip_of_table_end");
  
  extern struct of_device_id __irqchip_of_table[];
  
  void __init irqchip_init(void)
  {
  	of_irq_init(__irqchip_of_table);
  	acpi_probe_device_table(irqchip);
  }
  
  int platform_irqchip_probe(struct platform_device *pdev)
  {
  	struct device_node *np = pdev->dev.of_node;
  	struct device_node *par_np = of_irq_find_parent(np);
  	of_irq_init_cb_t irq_init_cb = of_device_get_match_data(&pdev->dev);
  
  	if (!irq_init_cb)
  		return -EINVAL;
  
  	if (par_np == np)
  		par_np = NULL;
  
  	/*
  	 * If there's a parent interrupt controller and  none of the parent irq
  	 * domains have been registered, that means the parent interrupt
  	 * controller has not been initialized yet.  it's not time for this
  	 * interrupt controller to initialize. So, defer probe of this
  	 * interrupt controller. The actual initialization callback of this
  	 * interrupt controller can check for specific domains as necessary.
  	 */
  	if (par_np && !irq_find_matching_host(par_np, DOMAIN_BUS_ANY))
  		return -EPROBE_DEFER;
  
  	return irq_init_cb(np, par_np);
  }
  EXPORT_SYMBOL_GPL(platform_irqchip_probe);
  