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