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 <fdtdec.h> 16 #include <linker_lists.h> 17 #include <linux/list.h> 18 19 struct driver_info; 20 21 /* Driver is active (probed). Cleared when it is removed */ 22 #define DM_FLAG_ACTIVATED (1 << 0) 23 24 /* DM is responsible for allocating and freeing platdata */ 25 #define DM_FLAG_ALLOC_PDATA (1 << 1) 26 27 /* DM should init this device prior to relocation */ 28 #define DM_FLAG_PRE_RELOC (1 << 2) 29 30 /* DM is responsible for allocating and freeing parent_platdata */ 31 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3) 32 33 /** 34 * struct udevice - An instance of a driver 35 * 36 * This holds information about a device, which is a driver bound to a 37 * particular port or peripheral (essentially a driver instance). 38 * 39 * A device will come into existence through a 'bind' call, either due to 40 * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node 41 * in the device tree (in which case of_offset is >= 0). In the latter case 42 * we translate the device tree information into platdata in a function 43 * implemented by the driver ofdata_to_platdata method (called just before the 44 * probe method if the device has a device tree node. 45 * 46 * All three of platdata, priv and uclass_priv can be allocated by the 47 * driver, or you can use the auto_alloc_size members of struct driver and 48 * struct uclass_driver to have driver model do this automatically. 49 * 50 * @driver: The driver used by this device 51 * @name: Name of device, typically the FDT node name 52 * @platdata: Configuration data for this device 53 * @parent_platdata: The parent bus's configuration data for this device 54 * @of_offset: Device tree node offset for this device (- for none) 55 * @of_id: Pointer to the udevice_id structure which created the device 56 * @parent: Parent of this device, or NULL for the top level device 57 * @priv: Private data for this device 58 * @uclass: Pointer to uclass for this device 59 * @uclass_priv: The uclass's private data for this device 60 * @parent_priv: The parent's private data for this device 61 * @uclass_node: Used by uclass to link its devices 62 * @child_head: List of children of this device 63 * @sibling_node: Next device in list of all devices 64 * @flags: Flags for this device DM_FLAG_... 65 * @req_seq: Requested sequence number for this device (-1 = any) 66 * @seq: Allocated sequence number for this device (-1 = none). This is set up 67 * when the device is probed and will be unique within the device's uclass. 68 */ 69 struct udevice { 70 struct driver *driver; 71 const char *name; 72 void *platdata; 73 void *parent_platdata; 74 int of_offset; 75 const struct udevice_id *of_id; 76 struct udevice *parent; 77 void *priv; 78 struct uclass *uclass; 79 void *uclass_priv; 80 void *parent_priv; 81 struct list_head uclass_node; 82 struct list_head child_head; 83 struct list_head sibling_node; 84 uint32_t flags; 85 int req_seq; 86 int seq; 87 }; 88 89 /* Maximum sequence number supported */ 90 #define DM_MAX_SEQ 999 91 92 /* Returns the operations for a device */ 93 #define device_get_ops(dev) (dev->driver->ops) 94 95 /* Returns non-zero if the device is active (probed and not removed) */ 96 #define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED) 97 98 /** 99 * struct udevice_id - Lists the compatible strings supported by a driver 100 * @compatible: Compatible string 101 * @data: Data for this compatible string 102 */ 103 struct udevice_id { 104 const char *compatible; 105 ulong data; 106 }; 107 108 #ifdef CONFIG_OF_CONTROL 109 #define of_match_ptr(_ptr) (_ptr) 110 #else 111 #define of_match_ptr(_ptr) NULL 112 #endif /* CONFIG_OF_CONTROL */ 113 114 /** 115 * struct driver - A driver for a feature or peripheral 116 * 117 * This holds methods for setting up a new device, and also removing it. 118 * The device needs information to set itself up - this is provided either 119 * by platdata or a device tree node (which we find by looking up 120 * matching compatible strings with of_match). 121 * 122 * Drivers all belong to a uclass, representing a class of devices of the 123 * same type. Common elements of the drivers can be implemented in the uclass, 124 * or the uclass can provide a consistent interface to the drivers within 125 * it. 126 * 127 * @name: Device name 128 * @id: Identiies the uclass we belong to 129 * @of_match: List of compatible strings to match, and any identifying data 130 * for each. 131 * @bind: Called to bind a device to its driver 132 * @probe: Called to probe a device, i.e. activate it 133 * @remove: Called to remove a device, i.e. de-activate it 134 * @unbind: Called to unbind a device from its driver 135 * @ofdata_to_platdata: Called before probe to decode device tree data 136 * @child_post_bind: Called after a new child has been bound 137 * @child_pre_probe: Called before a child device is probed. The device has 138 * memory allocated but it has not yet been probed. 139 * @child_post_remove: Called after a child device is removed. The device 140 * has memory allocated but its device_remove() method has been called. 141 * @priv_auto_alloc_size: If non-zero this is the size of the private data 142 * to be allocated in the device's ->priv pointer. If zero, then the driver 143 * is responsible for allocating any data required. 144 * @platdata_auto_alloc_size: If non-zero this is the size of the 145 * platform data to be allocated in the device's ->platdata pointer. 146 * This is typically only useful for device-tree-aware drivers (those with 147 * an of_match), since drivers which use platdata will have the data 148 * provided in the U_BOOT_DEVICE() instantiation. 149 * @per_child_auto_alloc_size: Each device can hold private data owned by 150 * its parent. If required this will be automatically allocated if this 151 * value is non-zero. 152 * TODO(sjg@chromium.org): I'm considering dropping this, and just having 153 * device_probe_child() pass it in. So far the use case for allocating it 154 * is SPI, but I found that unsatisfactory. Since it is here I will leave it 155 * until things are clearer. 156 * @per_child_platdata_auto_alloc_size: A bus likes to store information about 157 * its children. If non-zero this is the size of this data, to be allocated 158 * in the child's parent_platdata pointer. 159 * @ops: Driver-specific operations. This is typically a list of function 160 * pointers defined by the driver, to implement driver functions required by 161 * the uclass. 162 * @flags: driver flags - see DM_FLAGS_... 163 */ 164 struct driver { 165 char *name; 166 enum uclass_id id; 167 const struct udevice_id *of_match; 168 int (*bind)(struct udevice *dev); 169 int (*probe)(struct udevice *dev); 170 int (*remove)(struct udevice *dev); 171 int (*unbind)(struct udevice *dev); 172 int (*ofdata_to_platdata)(struct udevice *dev); 173 int (*child_post_bind)(struct udevice *dev); 174 int (*child_pre_probe)(struct udevice *dev); 175 int (*child_post_remove)(struct udevice *dev); 176 int priv_auto_alloc_size; 177 int platdata_auto_alloc_size; 178 int per_child_auto_alloc_size; 179 int per_child_platdata_auto_alloc_size; 180 const void *ops; /* driver-specific operations */ 181 uint32_t flags; 182 }; 183 184 /* Declare a new U-Boot driver */ 185 #define U_BOOT_DRIVER(__name) \ 186 ll_entry_declare(struct driver, __name, driver) 187 188 /** 189 * dev_get_platdata() - Get the platform data for a device 190 * 191 * This checks that dev is not NULL, but no other checks for now 192 * 193 * @dev Device to check 194 * @return platform data, or NULL if none 195 */ 196 void *dev_get_platdata(struct udevice *dev); 197 198 /** 199 * dev_get_parent_platdata() - Get the parent platform data for a device 200 * 201 * This checks that dev is not NULL, but no other checks for now 202 * 203 * @dev Device to check 204 * @return parent's platform data, or NULL if none 205 */ 206 void *dev_get_parent_platdata(struct udevice *dev); 207 208 /** 209 * dev_get_parentdata() - Get the parent data for a device 210 * 211 * The parent data is data stored in the device but owned by the parent. 212 * For example, a USB device may have parent data which contains information 213 * about how to talk to the device over USB. 214 * 215 * This checks that dev is not NULL, but no other checks for now 216 * 217 * @dev Device to check 218 * @return parent data, or NULL if none 219 */ 220 void *dev_get_parentdata(struct udevice *dev); 221 222 /** 223 * dev_get_priv() - Get the private data for a device 224 * 225 * This checks that dev is not NULL, but no other checks for now 226 * 227 * @dev Device to check 228 * @return private data, or NULL if none 229 */ 230 void *dev_get_priv(struct udevice *dev); 231 232 /** 233 * struct dev_get_parent() - Get the parent of a device 234 * 235 * @child: Child to check 236 * @return parent of child, or NULL if this is the root device 237 */ 238 struct udevice *dev_get_parent(struct udevice *child); 239 240 /** 241 * dev_get_of_data() - get the device tree data used to bind a device 242 * 243 * When a device is bound using a device tree node, it matches a 244 * particular compatible string as in struct udevice_id. This function 245 * returns the associated data value for that compatible string 246 */ 247 ulong dev_get_of_data(struct udevice *dev); 248 249 /* 250 * device_get_uclass_id() - return the uclass ID of a device 251 * 252 * @dev: Device to check 253 * @return uclass ID for the device 254 */ 255 enum uclass_id device_get_uclass_id(struct udevice *dev); 256 257 /** 258 * device_get_child() - Get the child of a device by index 259 * 260 * Returns the numbered child, 0 being the first. This does not use 261 * sequence numbers, only the natural order. 262 * 263 * @dev: Parent device to check 264 * @index: Child index 265 * @devp: Returns pointer to device 266 */ 267 int device_get_child(struct udevice *parent, int index, struct udevice **devp); 268 269 /** 270 * device_find_child_by_seq() - Find a child device based on a sequence 271 * 272 * This searches for a device with the given seq or req_seq. 273 * 274 * For seq, if an active device has this sequence it will be returned. 275 * If there is no such device then this will return -ENODEV. 276 * 277 * For req_seq, if a device (whether activated or not) has this req_seq 278 * value, that device will be returned. This is a strong indication that 279 * the device will receive that sequence when activated. 280 * 281 * @parent: Parent device 282 * @seq_or_req_seq: Sequence number to find (0=first) 283 * @find_req_seq: true to find req_seq, false to find seq 284 * @devp: Returns pointer to device (there is only one per for each seq). 285 * Set to NULL if none is found 286 * @return 0 if OK, -ve on error 287 */ 288 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq, 289 bool find_req_seq, struct udevice **devp); 290 291 /** 292 * device_get_child_by_seq() - Get a child device based on a sequence 293 * 294 * If an active device has this sequence it will be returned. If there is no 295 * such device then this will check for a device that is requesting this 296 * sequence. 297 * 298 * The device is probed to activate it ready for use. 299 * 300 * @parent: Parent device 301 * @seq: Sequence number to find (0=first) 302 * @devp: Returns pointer to device (there is only one per for each seq) 303 * Set to NULL if none is found 304 * @return 0 if OK, -ve on error 305 */ 306 int device_get_child_by_seq(struct udevice *parent, int seq, 307 struct udevice **devp); 308 309 /** 310 * device_find_child_by_of_offset() - Find a child device based on FDT offset 311 * 312 * Locates a child device by its device tree offset. 313 * 314 * @parent: Parent device 315 * @of_offset: Device tree offset to find 316 * @devp: Returns pointer to device if found, otherwise this is set to NULL 317 * @return 0 if OK, -ve on error 318 */ 319 int device_find_child_by_of_offset(struct udevice *parent, int of_offset, 320 struct udevice **devp); 321 322 /** 323 * device_get_child_by_of_offset() - Get a child device based on FDT offset 324 * 325 * Locates a child device by its device tree offset. 326 * 327 * The device is probed to activate it ready for use. 328 * 329 * @parent: Parent device 330 * @of_offset: Device tree offset to find 331 * @devp: Returns pointer to device if found, otherwise this is set to NULL 332 * @return 0 if OK, -ve on error 333 */ 334 int device_get_child_by_of_offset(struct udevice *parent, int seq, 335 struct udevice **devp); 336 337 /** 338 * device_find_first_child() - Find the first child of a device 339 * 340 * @parent: Parent device to search 341 * @devp: Returns first child device, or NULL if none 342 * @return 0 343 */ 344 int device_find_first_child(struct udevice *parent, struct udevice **devp); 345 346 /** 347 * device_find_first_child() - Find the first child of a device 348 * 349 * @devp: Pointer to previous child device on entry. Returns pointer to next 350 * child device, or NULL if none 351 * @return 0 352 */ 353 int device_find_next_child(struct udevice **devp); 354 355 /** 356 * dev_get_addr() - Get the reg property of a device 357 * 358 * @dev: Pointer to a device 359 * 360 * @return addr 361 */ 362 fdt_addr_t dev_get_addr(struct udevice *dev); 363 364 #endif 365