1 /*
2  * Copyright (C) 2012 Thomas Petazzoni
3  *
4  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
5  *
6  * This file is licensed under the terms of the GNU General Public
7  * License version 2.  This program is licensed "as is" without any
8  * warranty of any kind, whether express or implied.
9  */
10 
11 #include <linux/acpi.h>
12 #include <linux/init.h>
13 #include <linux/of.h>
14 #include <linux/of_irq.h>
15 #include <linux/irqchip.h>
16 #include <linux/platform_device.h>
17 
18 /*
19  * This special of_device_id is the sentinel at the end of the
20  * of_device_id[] array of all irqchips. It is automatically placed at
21  * the end of the array by the linker, thanks to being part of a
22  * special section.
23  */
24 static const struct of_device_id
25 irqchip_of_match_end __used __section("__irqchip_of_table_end");
26 
27 extern struct of_device_id __irqchip_of_table[];
28 
irqchip_init(void)29 void __init irqchip_init(void)
30 {
31 	of_irq_init(__irqchip_of_table);
32 	acpi_probe_device_table(irqchip);
33 }
34 
platform_irqchip_probe(struct platform_device * pdev)35 int platform_irqchip_probe(struct platform_device *pdev)
36 {
37 	struct device_node *np = pdev->dev.of_node;
38 	struct device_node *par_np = of_irq_find_parent(np);
39 	of_irq_init_cb_t irq_init_cb = of_device_get_match_data(&pdev->dev);
40 
41 	if (!irq_init_cb) {
42 		of_node_put(par_np);
43 		return -EINVAL;
44 	}
45 
46 	if (par_np == np)
47 		par_np = NULL;
48 
49 	/*
50 	 * If there's a parent interrupt controller and  none of the parent irq
51 	 * domains have been registered, that means the parent interrupt
52 	 * controller has not been initialized yet.  it's not time for this
53 	 * interrupt controller to initialize. So, defer probe of this
54 	 * interrupt controller. The actual initialization callback of this
55 	 * interrupt controller can check for specific domains as necessary.
56 	 */
57 	if (par_np && !irq_find_matching_host(par_np, DOMAIN_BUS_ANY)) {
58 		of_node_put(par_np);
59 		return -EPROBE_DEFER;
60 	}
61 
62 	return irq_init_cb(np, par_np);
63 }
64 EXPORT_SYMBOL_GPL(platform_irqchip_probe);
65