iio-trig-interrupt.c 2.5 KB

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