1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Industrial I/O - generic interrupt based trigger support
4 *
5 * Copyright (c) 2008-2013 Jonathan Cameron
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/platform_device.h>
11#include <linux/interrupt.h>
12#include <linux/slab.h>
13
14#include <linux/iio/iio.h>
15#include <linux/iio/trigger.h>
16
17
18struct iio_interrupt_trigger_info {
19	unsigned int irq;
20};
21
22static irqreturn_t iio_interrupt_trigger_poll(int irq, void *private)
23{
24	iio_trigger_poll(private);
25	return IRQ_HANDLED;
26}
27
28static const struct iio_trigger_ops iio_interrupt_trigger_ops = {
29};
30
31static int iio_interrupt_trigger_probe(struct platform_device *pdev)
32{
33	struct iio_interrupt_trigger_info *trig_info;
34	struct iio_trigger *trig;
35	unsigned long irqflags;
36	struct resource *irq_res;
37	int irq, ret = 0;
38
39	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
40
41	if (irq_res == NULL)
42		return -ENODEV;
43
44	irqflags = (irq_res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
45
46	irq = irq_res->start;
47
48	trig = iio_trigger_alloc("irqtrig%d", irq);
49	if (!trig) {
50		ret = -ENOMEM;
51		goto error_ret;
52	}
53
54	trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
55	if (!trig_info) {
56		ret = -ENOMEM;
57		goto error_free_trigger;
58	}
59	iio_trigger_set_drvdata(trig, trig_info);
60	trig_info->irq = irq;
61	trig->ops = &iio_interrupt_trigger_ops;
62	ret = request_irq(irq, iio_interrupt_trigger_poll,
63			  irqflags, trig->name, trig);
64	if (ret) {
65		dev_err(&pdev->dev,
66			"request IRQ-%d failed", irq);
67		goto error_free_trig_info;
68	}
69
70	ret = iio_trigger_register(trig);
71	if (ret)
72		goto error_release_irq;
73	platform_set_drvdata(pdev, trig);
74
75	return 0;
76
77/* First clean up the partly allocated trigger */
78error_release_irq:
79	free_irq(irq, trig);
80error_free_trig_info:
81	kfree(trig_info);
82error_free_trigger:
83	iio_trigger_free(trig);
84error_ret:
85	return ret;
86}
87
88static int iio_interrupt_trigger_remove(struct platform_device *pdev)
89{
90	struct iio_trigger *trig;
91	struct iio_interrupt_trigger_info *trig_info;
92
93	trig = platform_get_drvdata(pdev);
94	trig_info = iio_trigger_get_drvdata(trig);
95	iio_trigger_unregister(trig);
96	free_irq(trig_info->irq, trig);
97	kfree(trig_info);
98	iio_trigger_free(trig);
99
100	return 0;
101}
102
103static struct platform_driver iio_interrupt_trigger_driver = {
104	.probe = iio_interrupt_trigger_probe,
105	.remove = iio_interrupt_trigger_remove,
106	.driver = {
107		.name = "iio_interrupt_trigger",
108	},
109};
110
111module_platform_driver(iio_interrupt_trigger_driver);
112
113MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
114MODULE_DESCRIPTION("Interrupt trigger for the iio subsystem");
115MODULE_LICENSE("GPL v2");
116