LXR linux/drivers/iio/trigger/iio-trig-interrupt.c

   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(NULL, "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