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 /* DM is responsible for allocating and freeing uclass_platdata */ 34 #define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4) 35 36 /* Allocate driver private data on a DMA boundary */ 37 #define DM_FLAG_ALLOC_PRIV_DMA (1 << 5) 38 39 /** 40 * struct udevice - An instance of a driver 41 * 42 * This holds information about a device, which is a driver bound to a 43 * particular port or peripheral (essentially a driver instance). 44 * 45 * A device will come into existence through a 'bind' call, either due to 46 * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node 47 * in the device tree (in which case of_offset is >= 0). In the latter case 48 * we translate the device tree information into platdata in a function 49 * implemented by the driver ofdata_to_platdata method (called just before the 50 * probe method if the device has a device tree node. 51 * 52 * All three of platdata, priv and uclass_priv can be allocated by the 53 * driver, or you can use the auto_alloc_size members of struct driver and 54 * struct uclass_driver to have driver model do this automatically. 55 * 56 * @driver: The driver used by this device 57 * @name: Name of device, typically the FDT node name 58 * @platdata: Configuration data for this device 59 * @parent_platdata: The parent bus's configuration data for this device 60 * @uclass_platdata: The uclass's configuration data for this device 61 * @of_offset: Device tree node offset for this device (- for none) 62 * @driver_data: Driver data word for the entry that matched this device with 63 * its driver 64 * @parent: Parent of this device, or NULL for the top level device 65 * @priv: Private data for this device 66 * @uclass: Pointer to uclass for this device 67 * @uclass_priv: The uclass's private data for this device 68 * @parent_priv: The parent's private data for this device 69 * @uclass_node: Used by uclass to link its devices 70 * @child_head: List of children of this device 71 * @sibling_node: Next device in list of all devices 72 * @flags: Flags for this device DM_FLAG_... 73 * @req_seq: Requested sequence number for this device (-1 = any) 74 * @seq: Allocated sequence number for this device (-1 = none). This is set up 75 * when the device is probed and will be unique within the device's uclass. 76 */ 77 struct udevice { 78 const struct driver *driver; 79 const char *name; 80 void *platdata; 81 void *parent_platdata; 82 void *uclass_platdata; 83 int of_offset; 84 ulong driver_data; 85 struct udevice *parent; 86 void *priv; 87 struct uclass *uclass; 88 void *uclass_priv; 89 void *parent_priv; 90 struct list_head uclass_node; 91 struct list_head child_head; 92 struct list_head sibling_node; 93 uint32_t flags; 94 int req_seq; 95 int seq; 96 }; 97 98 /* Maximum sequence number supported */ 99 #define DM_MAX_SEQ 999 100 101 /* Returns the operations for a device */ 102 #define device_get_ops(dev) (dev->driver->ops) 103 104 /* Returns non-zero if the device is active (probed and not removed) */ 105 #define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED) 106 107 /** 108 * struct udevice_id - Lists the compatible strings supported by a driver 109 * @compatible: Compatible string 110 * @data: Data for this compatible string 111 */ 112 struct udevice_id { 113 const char *compatible; 114 ulong data; 115 }; 116 117 #ifdef CONFIG_OF_CONTROL 118 #define of_match_ptr(_ptr) (_ptr) 119 #else 120 #define of_match_ptr(_ptr) NULL 121 #endif /* CONFIG_OF_CONTROL */ 122 123 /** 124 * struct driver - A driver for a feature or peripheral 125 * 126 * This holds methods for setting up a new device, and also removing it. 127 * The device needs information to set itself up - this is provided either 128 * by platdata or a device tree node (which we find by looking up 129 * matching compatible strings with of_match). 130 * 131 * Drivers all belong to a uclass, representing a class of devices of the 132 * same type. Common elements of the drivers can be implemented in the uclass, 133 * or the uclass can provide a consistent interface to the drivers within 134 * it. 135 * 136 * @name: Device name 137 * @id: Identiies the uclass we belong to 138 * @of_match: List of compatible strings to match, and any identifying data 139 * for each. 140 * @bind: Called to bind a device to its driver 141 * @probe: Called to probe a device, i.e. activate it 142 * @remove: Called to remove a device, i.e. de-activate it 143 * @unbind: Called to unbind a device from its driver 144 * @ofdata_to_platdata: Called before probe to decode device tree data 145 * @child_post_bind: Called after a new child has been bound 146 * @child_pre_probe: Called before a child device is probed. The device has 147 * memory allocated but it has not yet been probed. 148 * @child_post_remove: Called after a child device is removed. The device 149 * has memory allocated but its device_remove() method has been called. 150 * @priv_auto_alloc_size: If non-zero this is the size of the private data 151 * to be allocated in the device's ->priv pointer. If zero, then the driver 152 * is responsible for allocating any data required. 153 * @platdata_auto_alloc_size: If non-zero this is the size of the 154 * platform data to be allocated in the device's ->platdata pointer. 155 * This is typically only useful for device-tree-aware drivers (those with 156 * an of_match), since drivers which use platdata will have the data 157 * provided in the U_BOOT_DEVICE() instantiation. 158 * @per_child_auto_alloc_size: Each device can hold private data owned by 159 * its parent. If required this will be automatically allocated if this 160 * value is non-zero. 161 * TODO(sjg@chromium.org): I'm considering dropping this, and just having 162 * device_probe_child() pass it in. So far the use case for allocating it 163 * is SPI, but I found that unsatisfactory. Since it is here I will leave it 164 * until things are clearer. 165 * @per_child_platdata_auto_alloc_size: A bus likes to store information about 166 * its children. If non-zero this is the size of this data, to be allocated 167 * in the child's parent_platdata pointer. 168 * @ops: Driver-specific operations. This is typically a list of function 169 * pointers defined by the driver, to implement driver functions required by 170 * the uclass. 171 * @flags: driver flags - see DM_FLAGS_... 172 */ 173 struct driver { 174 char *name; 175 enum uclass_id id; 176 const struct udevice_id *of_match; 177 int (*bind)(struct udevice *dev); 178 int (*probe)(struct udevice *dev); 179 int (*remove)(struct udevice *dev); 180 int (*unbind)(struct udevice *dev); 181 int (*ofdata_to_platdata)(struct udevice *dev); 182 int (*child_post_bind)(struct udevice *dev); 183 int (*child_pre_probe)(struct udevice *dev); 184 int (*child_post_remove)(struct udevice *dev); 185 int priv_auto_alloc_size; 186 int platdata_auto_alloc_size; 187 int per_child_auto_alloc_size; 188 int per_child_platdata_auto_alloc_size; 189 const void *ops; /* driver-specific operations */ 190 uint32_t flags; 191 }; 192 193 /* Declare a new U-Boot driver */ 194 #define U_BOOT_DRIVER(__name) \ 195 ll_entry_declare(struct driver, __name, driver) 196 197 /** 198 * dev_get_platdata() - Get the platform data for a device 199 * 200 * This checks that dev is not NULL, but no other checks for now 201 * 202 * @dev Device to check 203 * @return platform data, or NULL if none 204 */ 205 void *dev_get_platdata(struct udevice *dev); 206 207 /** 208 * dev_get_parent_platdata() - Get the parent platform data for a device 209 * 210 * This checks that dev is not NULL, but no other checks for now 211 * 212 * @dev Device to check 213 * @return parent's platform data, or NULL if none 214 */ 215 void *dev_get_parent_platdata(struct udevice *dev); 216 217 /** 218 * dev_get_uclass_platdata() - Get the uclass platform data for a device 219 * 220 * This checks that dev is not NULL, but no other checks for now 221 * 222 * @dev Device to check 223 * @return uclass's platform data, or NULL if none 224 */ 225 void *dev_get_uclass_platdata(struct udevice *dev); 226 227 /** 228 * dev_get_parentdata() - Get the parent data for a device 229 * 230 * The parent data is data stored in the device but owned by the parent. 231 * For example, a USB device may have parent data which contains information 232 * about how to talk to the device over USB. 233 * 234 * This checks that dev is not NULL, but no other checks for now 235 * 236 * @dev Device to check 237 * @return parent data, or NULL if none 238 */ 239 void *dev_get_parentdata(struct udevice *dev); 240 241 /** 242 * dev_get_priv() - Get the private data for a device 243 * 244 * This checks that dev is not NULL, but no other checks for now 245 * 246 * @dev Device to check 247 * @return private data, or NULL if none 248 */ 249 void *dev_get_priv(struct udevice *dev); 250 251 /** 252 * struct dev_get_parent() - Get the parent of a device 253 * 254 * @child: Child to check 255 * @return parent of child, or NULL if this is the root device 256 */ 257 struct udevice *dev_get_parent(struct udevice *child); 258 259 /** 260 * dev_get_uclass_priv() - Get the private uclass data for a device 261 * 262 * This checks that dev is not NULL, but no other checks for now 263 * 264 * @dev Device to check 265 * @return private uclass data for this device, or NULL if none 266 */ 267 void *dev_get_uclass_priv(struct udevice *dev); 268 269 /** 270 * dev_get_driver_data() - get the driver data used to bind a device 271 * 272 * When a device is bound using a device tree node, it matches a 273 * particular compatible string as in struct udevice_id. This function 274 * returns the associated data value for that compatible string. This is 275 * the 'data' field in struct udevice_id. 276 * 277 * For USB devices, this is the driver_info field in struct usb_device_id. 278 * 279 * @dev: Device to check 280 */ 281 ulong dev_get_driver_data(struct udevice *dev); 282 283 /** 284 * dev_get_driver_ops() - get the device's driver's operations 285 * 286 * This checks that dev is not NULL, and returns the pointer to device's 287 * driver's operations. 288 * 289 * @dev: Device to check 290 * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops 291 */ 292 const void *dev_get_driver_ops(struct udevice *dev); 293 294 /* 295 * device_get_uclass_id() - return the uclass ID of a device 296 * 297 * @dev: Device to check 298 * @return uclass ID for the device 299 */ 300 enum uclass_id device_get_uclass_id(struct udevice *dev); 301 302 /* 303 * dev_get_uclass_name() - return the uclass name of a device 304 * 305 * This checks that dev is not NULL. 306 * 307 * @dev: Device to check 308 * @return pointer to the uclass name for the device 309 */ 310 const char *dev_get_uclass_name(struct udevice *dev); 311 312 /** 313 * device_get_child() - Get the child of a device by index 314 * 315 * Returns the numbered child, 0 being the first. This does not use 316 * sequence numbers, only the natural order. 317 * 318 * @dev: Parent device to check 319 * @index: Child index 320 * @devp: Returns pointer to device 321 */ 322 int device_get_child(struct udevice *parent, int index, struct udevice **devp); 323 324 /** 325 * device_find_child_by_seq() - Find a child device based on a sequence 326 * 327 * This searches for a device with the given seq or req_seq. 328 * 329 * For seq, if an active device has this sequence it will be returned. 330 * If there is no such device then this will return -ENODEV. 331 * 332 * For req_seq, if a device (whether activated or not) has this req_seq 333 * value, that device will be returned. This is a strong indication that 334 * the device will receive that sequence when activated. 335 * 336 * @parent: Parent device 337 * @seq_or_req_seq: Sequence number to find (0=first) 338 * @find_req_seq: true to find req_seq, false to find seq 339 * @devp: Returns pointer to device (there is only one per for each seq). 340 * Set to NULL if none is found 341 * @return 0 if OK, -ve on error 342 */ 343 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq, 344 bool find_req_seq, struct udevice **devp); 345 346 /** 347 * device_get_child_by_seq() - Get a child device based on a sequence 348 * 349 * If an active device has this sequence it will be returned. If there is no 350 * such device then this will check for a device that is requesting this 351 * sequence. 352 * 353 * The device is probed to activate it ready for use. 354 * 355 * @parent: Parent device 356 * @seq: Sequence number to find (0=first) 357 * @devp: Returns pointer to device (there is only one per for each seq) 358 * Set to NULL if none is found 359 * @return 0 if OK, -ve on error 360 */ 361 int device_get_child_by_seq(struct udevice *parent, int seq, 362 struct udevice **devp); 363 364 /** 365 * device_find_child_by_of_offset() - Find a child device based on FDT offset 366 * 367 * Locates a child device by its device tree offset. 368 * 369 * @parent: Parent device 370 * @of_offset: Device tree offset to find 371 * @devp: Returns pointer to device if found, otherwise this is set to NULL 372 * @return 0 if OK, -ve on error 373 */ 374 int device_find_child_by_of_offset(struct udevice *parent, int of_offset, 375 struct udevice **devp); 376 377 /** 378 * device_get_child_by_of_offset() - Get a child device based on FDT offset 379 * 380 * Locates a child device by its device tree offset. 381 * 382 * The device is probed to activate it ready for use. 383 * 384 * @parent: Parent device 385 * @of_offset: Device tree offset to find 386 * @devp: Returns pointer to device if found, otherwise this is set to NULL 387 * @return 0 if OK, -ve on error 388 */ 389 int device_get_child_by_of_offset(struct udevice *parent, int seq, 390 struct udevice **devp); 391 392 /** 393 * device_find_first_child() - Find the first child of a device 394 * 395 * @parent: Parent device to search 396 * @devp: Returns first child device, or NULL if none 397 * @return 0 398 */ 399 int device_find_first_child(struct udevice *parent, struct udevice **devp); 400 401 /** 402 * device_find_first_child() - Find the first child of a device 403 * 404 * @devp: Pointer to previous child device on entry. Returns pointer to next 405 * child device, or NULL if none 406 * @return 0 407 */ 408 int device_find_next_child(struct udevice **devp); 409 410 /** 411 * dev_get_addr() - Get the reg property of a device 412 * 413 * @dev: Pointer to a device 414 * 415 * @return addr 416 */ 417 fdt_addr_t dev_get_addr(struct udevice *dev); 418 419 /** 420 * device_has_children() - check if a device has any children 421 * 422 * @dev: Device to check 423 * @return true if the device has one or more children 424 */ 425 bool device_has_children(struct udevice *dev); 426 427 /** 428 * device_has_active_children() - check if a device has any active children 429 * 430 * @dev: Device to check 431 * @return true if the device has one or more children and at least one of 432 * them is active (probed). 433 */ 434 bool device_has_active_children(struct udevice *dev); 435 436 /** 437 * device_is_last_sibling() - check if a device is the last sibling 438 * 439 * This function can be useful for display purposes, when special action needs 440 * to be taken when displaying the last sibling. This can happen when a tree 441 * view of devices is being displayed. 442 * 443 * @dev: Device to check 444 * @return true if there are no more siblings after this one - i.e. is it 445 * last in the list. 446 */ 447 bool device_is_last_sibling(struct udevice *dev); 448 449 #endif 450