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 int iio_interrupt_trigger_probe(struct platform_device *pdev)
29{
30	struct iio_interrupt_trigger_info *trig_info;
31	struct iio_trigger *trig;
32	unsigned long irqflags;
33	struct resource *irq_res;
34	int irq, ret = 0;
35
36	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
37
38	if (irq_res == NULL)
39		return -ENODEV;
40
41	irqflags = (irq_res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
42
43	irq = irq_res->start;
44
45	trig = iio_trigger_alloc(NULL, "irqtrig%d", irq);
46	if (!trig) {
47		ret = -ENOMEM;
48		goto error_ret;
49	}
50
51	trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
52	if (!trig_info) {
53		ret = -ENOMEM;
54		goto error_free_trigger;
55	}
56	iio_trigger_set_drvdata(trig, trig_info);
57	trig_info->irq = irq;
58	ret = request_irq(irq, iio_interrupt_trigger_poll,
59			  irqflags, trig->name, trig);
60	if (ret) {
61		dev_err(&pdev->dev,
62			"request IRQ-%d failed", irq);
63		goto error_free_trig_info;
64	}
65
66	ret = iio_trigger_register(trig);
67	if (ret)
68		goto error_release_irq;
69	platform_set_drvdata(pdev, trig);
70
71	return 0;
72
73/* First clean up the partly allocated trigger */
74error_release_irq:
75	free_irq(irq, trig);
76error_free_trig_info:
77	kfree(trig_info);
78error_free_trigger:
79	iio_trigger_free(trig);
80error_ret:
81	return ret;
82}
83
84static void iio_interrupt_trigger_remove(struct platform_device *pdev)
85{
86	struct iio_trigger *trig;
87	struct iio_interrupt_trigger_info *trig_info;
88
89	trig = platform_get_drvdata(pdev);
90	trig_info = iio_trigger_get_drvdata(trig);
91	iio_trigger_unregister(trig);
92	free_irq(trig_info->irq, trig);
93	kfree(trig_info);
94	iio_trigger_free(trig);
95}
96
97static struct platform_driver iio_interrupt_trigger_driver = {
98	.probe = iio_interrupt_trigger_probe,
99	.remove_new = iio_interrupt_trigger_remove,
100	.driver = {
101		.name = "iio_interrupt_trigger",
102	},
103};
104
105module_platform_driver(iio_interrupt_trigger_driver);
106
107MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
108MODULE_DESCRIPTION("Interrupt trigger for the iio subsystem");
109MODULE_LICENSE("GPL v2");
110