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 = 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");