1 /* 2 * Copyright (c) 2013 Google, Inc 3 * 4 * (C) Copyright 2012 5 * Pavel Herrmann <morpheus.ibis@gmail.com> 6 * Marek Vasut <marex@denx.de> 7 * 8 * SPDX-License-Identifier: GPL-2.0+ 9 */ 10 11 #ifndef _DM_DEVICE_H 12 #define _DM_DEVICE_H 13 14 #include <dm/uclass-id.h> 15 #include <linker_lists.h> 16 #include <linux/list.h> 17 18 struct driver_info; 19 20 /* Driver is active (probed). Cleared when it is removed */ 21 #define DM_FLAG_ACTIVATED (1 << 0) 22 23 /* DM is responsible for allocating and freeing platdata */ 24 #define DM_FLAG_ALLOC_PDATA (1 << 1) 25 26 /* DM should init this device prior to relocation */ 27 #define DM_FLAG_PRE_RELOC (1 << 2) 28 29 /** 30 * struct udevice - An instance of a driver 31 * 32 * This holds information about a device, which is a driver bound to a 33 * particular port or peripheral (essentially a driver instance). 34 * 35 * A device will come into existence through a 'bind' call, either due to 36 * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node 37 * in the device tree (in which case of_offset is >= 0). In the latter case 38 * we translate the device tree information into platdata in a function 39 * implemented by the driver ofdata_to_platdata method (called just before the 40 * probe method if the device has a device tree node. 41 * 42 * All three of platdata, priv and uclass_priv can be allocated by the 43 * driver, or you can use the auto_alloc_size members of struct driver and 44 * struct uclass_driver to have driver model do this automatically. 45 * 46 * @driver: The driver used by this device 47 * @name: Name of device, typically the FDT node name 48 * @platdata: Configuration data for this device 49 * @of_offset: Device tree node offset for this device (- for none) 50 * @parent: Parent of this device, or NULL for the top level device 51 * @priv: Private data for this device 52 * @uclass: Pointer to uclass for this device 53 * @uclass_priv: The uclass's private data for this device 54 * @uclass_node: Used by uclass to link its devices 55 * @child_head: List of children of this device 56 * @sibling_node: Next device in list of all devices 57 * @flags: Flags for this device DM_FLAG_... 58 */ 59 struct udevice { 60 struct driver *driver; 61 const char *name; 62 void *platdata; 63 int of_offset; 64 struct udevice *parent; 65 void *priv; 66 struct uclass *uclass; 67 void *uclass_priv; 68 struct list_head uclass_node; 69 struct list_head child_head; 70 struct list_head sibling_node; 71 uint32_t flags; 72 }; 73 74 /* Returns the operations for a device */ 75 #define device_get_ops(dev) (dev->driver->ops) 76 77 /* Returns non-zero if the device is active (probed and not removed) */ 78 #define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED) 79 80 /** 81 * struct udevice_id - Lists the compatible strings supported by a driver 82 * @compatible: Compatible string 83 * @data: Data for this compatible string 84 */ 85 struct udevice_id { 86 const char *compatible; 87 ulong data; 88 }; 89 90 /** 91 * struct driver - A driver for a feature or peripheral 92 * 93 * This holds methods for setting up a new device, and also removing it. 94 * The device needs information to set itself up - this is provided either 95 * by platdata or a device tree node (which we find by looking up 96 * matching compatible strings with of_match). 97 * 98 * Drivers all belong to a uclass, representing a class of devices of the 99 * same type. Common elements of the drivers can be implemented in the uclass, 100 * or the uclass can provide a consistent interface to the drivers within 101 * it. 102 * 103 * @name: Device name 104 * @id: Identiies the uclass we belong to 105 * @of_match: List of compatible strings to match, and any identifying data 106 * for each. 107 * @bind: Called to bind a device to its driver 108 * @probe: Called to probe a device, i.e. activate it 109 * @remove: Called to remove a device, i.e. de-activate it 110 * @unbind: Called to unbind a device from its driver 111 * @ofdata_to_platdata: Called before probe to decode device tree data 112 * @priv_auto_alloc_size: If non-zero this is the size of the private data 113 * to be allocated in the device's ->priv pointer. If zero, then the driver 114 * is responsible for allocating any data required. 115 * @platdata_auto_alloc_size: If non-zero this is the size of the 116 * platform data to be allocated in the device's ->platdata pointer. 117 * This is typically only useful for device-tree-aware drivers (those with 118 * an of_match), since drivers which use platdata will have the data 119 * provided in the U_BOOT_DEVICE() instantiation. 120 * ops: Driver-specific operations. This is typically a list of function 121 * pointers defined by the driver, to implement driver functions required by 122 * the uclass. 123 * @flags: driver flags - see DM_FLAGS_... 124 */ 125 struct driver { 126 char *name; 127 enum uclass_id id; 128 const struct udevice_id *of_match; 129 int (*bind)(struct udevice *dev); 130 int (*probe)(struct udevice *dev); 131 int (*remove)(struct udevice *dev); 132 int (*unbind)(struct udevice *dev); 133 int (*ofdata_to_platdata)(struct udevice *dev); 134 int priv_auto_alloc_size; 135 int platdata_auto_alloc_size; 136 const void *ops; /* driver-specific operations */ 137 uint32_t flags; 138 }; 139 140 /* Declare a new U-Boot driver */ 141 #define U_BOOT_DRIVER(__name) \ 142 ll_entry_declare(struct driver, __name, driver) 143 144 /** 145 * dev_get_platdata() - Get the platform data for a device 146 * 147 * This checks that dev is not NULL, but no other checks for now 148 * 149 * @dev Device to check 150 * @return platform data, or NULL if none 151 */ 152 void *dev_get_platdata(struct udevice *dev); 153 154 /** 155 * dev_get_priv() - Get the private data for a device 156 * 157 * This checks that dev is not NULL, but no other checks for now 158 * 159 * @dev Device to check 160 * @return private data, or NULL if none 161 */ 162 void *dev_get_priv(struct udevice *dev); 163 164 #endif 165