LXR linux/include/linux/mfd/core.h

   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
  14#ifndef MFD_CORE_H
  15#define MFD_CORE_H
  16
  17#include <linux/platform_device.h>
  18
  19struct irq_domain;
  20
  21/*
  22 * This struct describes the MFD part ("cell").
  23 * After registration the copy of this structure will become the platform data
  24 * of the resulting platform_device
  25 */
  26struct mfd_cell {
  27        const char              *name;
  28        int                     id;
  29
  30        /* refcounting for multiple drivers to use a single cell */
  31        atomic_t                *usage_count;
  32        int                     (*enable)(struct platform_device *dev);
  33        int                     (*disable)(struct platform_device *dev);
  34
  35        int                     (*suspend)(struct platform_device *dev);
  36        int                     (*resume)(struct platform_device *dev);
  37
  38        /* platform data passed to the sub devices drivers */
  39        void                    *platform_data;
  40        size_t                  pdata_size;
  41        /*
  42         * Device Tree compatible string
  43         * See: Documentation/devicetree/usage-model.txt Chapter 2.2 for details
  44         */
  45        const char              *of_compatible;
  46
  47        /*
  48         * These resources can be specified relative to the parent device.
  49         * For accessing hardware you should use resources from the platform dev
  50         */
  51        int                     num_resources;
  52        const struct resource   *resources;
  53
  54        /* don't check for resource conflicts */
  55        bool                    ignore_resource_conflicts;
  56
  57        /*
  58         * Disable runtime PM callbacks for this subdevice - see
  59         * pm_runtime_no_callbacks().
  60         */
  61        bool                    pm_runtime_no_callbacks;
  62};
  63
  64/*
  65 * Convenience functions for clients using shared cells.  Refcounting
  66 * happens automatically, with the cell's enable/disable callbacks
  67 * being called only when a device is first being enabled or no other
  68 * clients are making use of it.
  69 */
  70extern int mfd_cell_enable(struct platform_device *pdev);
  71extern int mfd_cell_disable(struct platform_device *pdev);
  72
  73/*
  74 * "Clone" multiple platform devices for a single cell. This is to be used
  75 * for devices that have multiple users of a cell.  For example, if an mfd
  76 * driver wants the cell "foo" to be used by a GPIO driver, an MTD driver,
  77 * and a platform driver, the following bit of code would be use after first
  78 * calling mfd_add_devices():
  79 *
  80 * const char *fclones[] = { "foo-gpio", "foo-mtd" };
  81 * err = mfd_clone_cells("foo", fclones, ARRAY_SIZE(fclones));
  82 *
  83 * Each driver (MTD, GPIO, and platform driver) would then register
  84 * platform_drivers for "foo-mtd", "foo-gpio", and "foo", respectively.
  85 * The cell's .enable/.disable hooks should be used to deal with hardware
  86 * resource contention.
  87 */
  88extern int mfd_clone_cell(const char *cell, const char **clones,
  89                size_t n_clones);
  90
  91/*
  92 * Given a platform device that's been created by mfd_add_devices(), fetch
  93 * the mfd_cell that created it.
  94 */
  95static inline const struct mfd_cell *mfd_get_cell(struct platform_device *pdev)
  96{
  97        return pdev->mfd_cell;
  98}
  99
 100extern int mfd_add_devices(struct device *parent, int id,
 101                           struct mfd_cell *cells, int n_devs,
 102                           struct resource *mem_base,
 103                           int irq_base, struct irq_domain *irq_domain);
 104
 105extern void mfd_remove_devices(struct device *parent);
 106
 107#endif
 108