iio-trig-interrupt.c 2.4 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 int iio_interrupt_trigger_probe(struct platform_device *pdev)
  23. {
  24. struct iio_interrupt_trigger_info *trig_info;
  25. struct iio_trigger *trig;
  26. unsigned long irqflags;
  27. struct resource *irq_res;
  28. int irq, ret = 0;
  29. irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
  30. if (irq_res == NULL)
  31. return -ENODEV;
  32. irqflags = (irq_res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
  33. irq = irq_res->start;
  34. trig = iio_trigger_alloc(NULL, "irqtrig%d", irq);
  35. if (!trig) {
  36. ret = -ENOMEM;
  37. goto error_ret;
  38. }
  39. trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
  40. if (!trig_info) {
  41. ret = -ENOMEM;
  42. goto error_free_trigger;
  43. }
  44. iio_trigger_set_drvdata(trig, trig_info);
  45. trig_info->irq = irq;
  46. ret = request_irq(irq, iio_interrupt_trigger_poll,
  47. irqflags, trig->name, trig);
  48. if (ret) {
  49. dev_err(&pdev->dev,
  50. "request IRQ-%d failed", irq);
  51. goto error_free_trig_info;
  52. }
  53. ret = iio_trigger_register(trig);
  54. if (ret)
  55. goto error_release_irq;
  56. platform_set_drvdata(pdev, trig);
  57. return 0;
  58. /* First clean up the partly allocated trigger */
  59. error_release_irq:
  60. free_irq(irq, trig);
  61. error_free_trig_info:
  62. kfree(trig_info);
  63. error_free_trigger:
  64. iio_trigger_free(trig);
  65. error_ret:
  66. return ret;
  67. }
  68. static int iio_interrupt_trigger_remove(struct platform_device *pdev)
  69. {
  70. struct iio_trigger *trig;
  71. struct iio_interrupt_trigger_info *trig_info;
  72. trig = platform_get_drvdata(pdev);
  73. trig_info = iio_trigger_get_drvdata(trig);
  74. iio_trigger_unregister(trig);
  75. free_irq(trig_info->irq, trig);
  76. kfree(trig_info);
  77. iio_trigger_free(trig);
  78. return 0;
  79. }
  80. static struct platform_driver iio_interrupt_trigger_driver = {
  81. .probe = iio_interrupt_trigger_probe,
  82. .remove = iio_interrupt_trigger_remove,
  83. .driver = {
  84. .name = "iio_interrupt_trigger",
  85. },
  86. };
  87. module_platform_driver(iio_interrupt_trigger_driver);
  88. MODULE_AUTHOR("Jonathan Cameron <[email protected]>");
  89. MODULE_DESCRIPTION("Interrupt trigger for the iio subsystem");
  90. MODULE_LICENSE("GPL v2");