Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
19/*
20 * This struct describes the MFD part ("cell").
21 * After registration the copy of this structure will become the platform data
22 * of the resulting platform_device
23 */
24struct mfd_cell {
25 const char *name;
26 int id;
27
28 /* refcounting for multiple drivers to use a single cell */
29 atomic_t *usage_count;
30 int (*enable)(struct platform_device *dev);
31 int (*disable)(struct platform_device *dev);
32
33 int (*suspend)(struct platform_device *dev);
34 int (*resume)(struct platform_device *dev);
35
36 /* mfd_data can be used to pass data to client drivers */
37 void *mfd_data;
38
39 /*
40 * These resources can be specified relative to the parent device.
41 * For accessing hardware you should use resources from the platform dev
42 */
43 int num_resources;
44 const struct resource *resources;
45
46 /* don't check for resource conflicts */
47 bool ignore_resource_conflicts;
48
49 /*
50 * Disable runtime PM callbacks for this subdevice - see
51 * pm_runtime_no_callbacks().
52 */
53 bool pm_runtime_no_callbacks;
54};
55
56/*
57 * Convenience functions for clients using shared cells. Refcounting
58 * happens automatically, with the cell's enable/disable callbacks
59 * being called only when a device is first being enabled or no other
60 * clients are making use of it.
61 */
62extern int mfd_cell_enable(struct platform_device *pdev);
63extern int mfd_cell_disable(struct platform_device *pdev);
64
65/*
66 * "Clone" multiple platform devices for a single cell. This is to be used
67 * for devices that have multiple users of a cell. For example, if an mfd
68 * driver wants the cell "foo" to be used by a GPIO driver, an MTD driver,
69 * and a platform driver, the following bit of code would be use after first
70 * calling mfd_add_devices():
71 *
72 * const char *fclones[] = { "foo-gpio", "foo-mtd" };
73 * err = mfd_clone_cells("foo", fclones, ARRAY_SIZE(fclones));
74 *
75 * Each driver (MTD, GPIO, and platform driver) would then register
76 * platform_drivers for "foo-mtd", "foo-gpio", and "foo", respectively.
77 * The cell's .enable/.disable hooks should be used to deal with hardware
78 * resource contention.
79 */
80extern int mfd_clone_cell(const char *cell, const char **clones,
81 size_t n_clones);
82
83/*
84 * Given a platform device that's been created by mfd_add_devices(), fetch
85 * the mfd_cell that created it.
86 */
87static inline const struct mfd_cell *mfd_get_cell(struct platform_device *pdev)
88{
89 return pdev->mfd_cell;
90}
91
92/*
93 * Given a platform device that's been created by mfd_add_devices(), fetch
94 * the .mfd_data entry from the mfd_cell that created it.
95 * Otherwise just return the platform_data pointer.
96 * This maintains compatibility with platform drivers whose devices aren't
97 * created by the mfd layer, and expect platform_data to contain what would've
98 * otherwise been in mfd_data.
99 */
100static inline void *mfd_get_data(struct platform_device *pdev)
101{
102 const struct mfd_cell *cell = mfd_get_cell(pdev);
103
104 if (cell)
105 return cell->mfd_data;
106 else
107 return pdev->dev.platform_data;
108}
109
110extern int mfd_add_devices(struct device *parent, int id,
111 struct mfd_cell *cells, int n_devs,
112 struct resource *mem_base,
113 int irq_base);
114
115extern void mfd_remove_devices(struct device *parent);
116
117#endif