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  */
24 struct 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 	/* platform data passed to the sub devices drivers */
37 	void			*platform_data;
38 	size_t			pdata_size;
39 
40 	/*
41 	 * These resources can be specified relative to the parent device.
42 	 * For accessing hardware you should use resources from the platform dev
43 	 */
44 	int			num_resources;
45 	const struct resource	*resources;
46 
47 	/* don't check for resource conflicts */
48 	bool			ignore_resource_conflicts;
49 
50 	/*
51 	 * Disable runtime PM callbacks for this subdevice - see
52 	 * pm_runtime_no_callbacks().
53 	 */
54 	bool			pm_runtime_no_callbacks;
55 };
56 
57 /*
58  * Convenience functions for clients using shared cells.  Refcounting
59  * happens automatically, with the cell's enable/disable callbacks
60  * being called only when a device is first being enabled or no other
61  * clients are making use of it.
62  */
63 extern int mfd_cell_enable(struct platform_device *pdev);
64 extern int mfd_cell_disable(struct platform_device *pdev);
65 
66 /*
67  * "Clone" multiple platform devices for a single cell. This is to be used
68  * for devices that have multiple users of a cell.  For example, if an mfd
69  * driver wants the cell "foo" to be used by a GPIO driver, an MTD driver,
70  * and a platform driver, the following bit of code would be use after first
71  * calling mfd_add_devices():
72  *
73  * const char *fclones[] = { "foo-gpio", "foo-mtd" };
74  * err = mfd_clone_cells("foo", fclones, ARRAY_SIZE(fclones));
75  *
76  * Each driver (MTD, GPIO, and platform driver) would then register
77  * platform_drivers for "foo-mtd", "foo-gpio", and "foo", respectively.
78  * The cell's .enable/.disable hooks should be used to deal with hardware
79  * resource contention.
80  */
81 extern int mfd_clone_cell(const char *cell, const char **clones,
82 		size_t n_clones);
83 
84 /*
85  * Given a platform device that's been created by mfd_add_devices(), fetch
86  * the mfd_cell that created it.
87  */
mfd_get_cell(struct platform_device * pdev)88 static inline const struct mfd_cell *mfd_get_cell(struct platform_device *pdev)
89 {
90 	return pdev->mfd_cell;
91 }
92 
93 extern int mfd_add_devices(struct device *parent, int id,
94 			   struct mfd_cell *cells, int n_devs,
95 			   struct resource *mem_base,
96 			   int irq_base);
97 
98 extern void mfd_remove_devices(struct device *parent);
99 
100 #endif
101