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");