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 /* 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 */ 62 extern int mfd_cell_enable(struct platform_device *pdev); 63 extern 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 */ 80 extern 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 */ 87 static inline const struct mfd_cell *mfd_get_cell(struct platform_device *pdev) 88 { 89 return pdev->dev.platform_data; 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 */ 96 static inline void *mfd_get_data(struct platform_device *pdev) 97 { 98 return mfd_get_cell(pdev)->mfd_data; 99 } 100 101 extern int mfd_add_devices(struct device *parent, int id, 102 struct mfd_cell *cells, int n_devs, 103 struct resource *mem_base, 104 int irq_base); 105 106 extern void mfd_remove_devices(struct device *parent); 107 108 #endif 109