core.h 3.1 KB

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  1. /*
  2. * drivers/mfd/mfd-core.h
  3. *
  4. * core MFD support
  5. * Copyright (c) 2006 Ian Molton
  6. * Copyright (c) 2007 Dmitry Baryshkov
  7. *
  8. * This program is free software; you can redistribute it and/or modify
  9. * it under the terms of the GNU General Public License version 2 as
  10. * published by the Free Software Foundation.
  11. *
  12. */
  13. #ifndef MFD_CORE_H
  14. #define MFD_CORE_H
  15. #include <linux/platform_device.h>
  16. /*
  17. * This struct describes the MFD part ("cell").
  18. * After registration the copy of this structure will become the platform data
  19. * of the resulting platform_device
  20. */
  21. struct mfd_cell {
  22. const char *name;
  23. int id;
  24. /* refcounting for multiple drivers to use a single cell */
  25. atomic_t *usage_count;
  26. int (*enable)(struct platform_device *dev);
  27. int (*disable)(struct platform_device *dev);
  28. int (*suspend)(struct platform_device *dev);
  29. int (*resume)(struct platform_device *dev);
  30. /* platform data passed to the sub devices drivers */
  31. void *platform_data;
  32. size_t pdata_size;
  33. /*
  34. * Device Tree compatible string
  35. * See: Documentation/devicetree/usage-model.txt Chapter 2.2 for details
  36. */
  37. const char *of_compatible;
  38. /*
  39. * These resources can be specified relative to the parent device.
  40. * For accessing hardware you should use resources from the platform dev
  41. */
  42. int num_resources;
  43. const struct resource *resources;
  44. /* don't check for resource conflicts */
  45. bool ignore_resource_conflicts;
  46. /*
  47. * Disable runtime PM callbacks for this subdevice - see
  48. * pm_runtime_no_callbacks().
  49. */
  50. bool pm_runtime_no_callbacks;
  51. };
  52. /*
  53. * Convenience functions for clients using shared cells. Refcounting
  54. * happens automatically, with the cell's enable/disable callbacks
  55. * being called only when a device is first being enabled or no other
  56. * clients are making use of it.
  57. */
  58. extern int mfd_cell_enable(struct platform_device *pdev);
  59. extern int mfd_cell_disable(struct platform_device *pdev);
  60. /*
  61. * "Clone" multiple platform devices for a single cell. This is to be used
  62. * for devices that have multiple users of a cell. For example, if an mfd
  63. * driver wants the cell "foo" to be used by a GPIO driver, an MTD driver,
  64. * and a platform driver, the following bit of code would be use after first
  65. * calling mfd_add_devices():
  66. *
  67. * const char *fclones[] = { "foo-gpio", "foo-mtd" };
  68. * err = mfd_clone_cells("foo", fclones, ARRAY_SIZE(fclones));
  69. *
  70. * Each driver (MTD, GPIO, and platform driver) would then register
  71. * platform_drivers for "foo-mtd", "foo-gpio", and "foo", respectively.
  72. * The cell's .enable/.disable hooks should be used to deal with hardware
  73. * resource contention.
  74. */
  75. extern int mfd_clone_cell(const char *cell, const char **clones,
  76. size_t n_clones);
  77. /*
  78. * Given a platform device that's been created by mfd_add_devices(), fetch
  79. * the mfd_cell that created it.
  80. */
  81. static inline const struct mfd_cell *mfd_get_cell(struct platform_device *pdev)
  82. {
  83. return pdev->mfd_cell;
  84. }
  85. extern int mfd_add_devices(struct device *parent, int id,
  86. struct mfd_cell *cells, int n_devs,
  87. struct resource *mem_base,
  88. int irq_base);
  89. extern void mfd_remove_devices(struct device *parent);
  90. #endif