1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (c) 2013 Google, Inc 4 * 5 * (C) Copyright 2012 6 * Pavel Herrmann <morpheus.ibis@gmail.com> 7 */ 8 9 #ifndef _DM_UCLASS_H 10 #define _DM_UCLASS_H 11 12 #include <dm/ofnode.h> 13 #include <dm/uclass-id.h> 14 #include <linker_lists.h> 15 #include <linux/list.h> 16 17 /** 18 * struct uclass - a U-Boot drive class, collecting together similar drivers 19 * 20 * A uclass provides an interface to a particular function, which is 21 * implemented by one or more drivers. Every driver belongs to a uclass even 22 * if it is the only driver in that uclass. An example uclass is GPIO, which 23 * provides the ability to change read inputs, set and clear outputs, etc. 24 * There may be drivers for on-chip SoC GPIO banks, I2C GPIO expanders and 25 * PMIC IO lines, all made available in a unified way through the uclass. 26 * 27 * @priv_: Private data for this uclass (do not access outside driver model) 28 * @uc_drv: The driver for the uclass itself, not to be confused with a 29 * 'struct driver' 30 * @dev_head: List of devices in this uclass (devices are attached to their 31 * uclass when their bind method is called) 32 * @sibling_node: Next uclass in the linked list of uclasses 33 */ 34 struct uclass { 35 void *priv_; 36 struct uclass_driver *uc_drv; 37 struct list_head dev_head; 38 struct list_head sibling_node; 39 }; 40 41 struct driver; 42 struct udevice; 43 44 /* Members of this uclass sequence themselves with aliases */ 45 #define DM_UC_FLAG_SEQ_ALIAS (1 << 0) 46 47 /* Members of this uclass without aliases don't get a sequence number */ 48 #define DM_UC_FLAG_NO_AUTO_SEQ (1 << 1) 49 50 /* Same as DM_FLAG_ALLOC_PRIV_DMA */ 51 #define DM_UC_FLAG_ALLOC_PRIV_DMA (1 << 5) 52 53 /** 54 * struct uclass_driver - Driver for the uclass 55 * 56 * A uclass_driver provides a consistent interface to a set of related 57 * drivers. 58 * 59 * @name: Name of uclass driver 60 * @id: ID number of this uclass 61 * @post_bind: Called after a new device is bound to this uclass 62 * @pre_unbind: Called before a device is unbound from this uclass 63 * @pre_probe: Called before a new device is probed 64 * @post_probe: Called after a new device is probed 65 * @pre_remove: Called before a device is removed 66 * @child_post_bind: Called after a child is bound to a device in this uclass 67 * @child_pre_probe: Called before a child in this uclass is probed 68 * @child_post_probe: Called after a child in this uclass is probed 69 * @init: Called to set up the uclass 70 * @destroy: Called to destroy the uclass 71 * @priv_auto: If non-zero this is the size of the private data 72 * to be allocated in the uclass's ->priv pointer. If zero, then the uclass 73 * driver is responsible for allocating any data required. 74 * @per_device_auto: Each device can hold private data owned 75 * by the uclass. If required this will be automatically allocated if this 76 * value is non-zero. 77 * @per_device_plat_auto: Each device can hold platform data 78 * owned by the uclass as 'dev->uclass_plat'. If the value is non-zero, 79 * then this will be automatically allocated. 80 * @per_child_auto: Each child device (of a parent in this 81 * uclass) can hold parent data for the device/uclass. This value is only 82 * used as a fallback if this member is 0 in the driver. 83 * @per_child_plat_auto: A bus likes to store information about 84 * its children. If non-zero this is the size of this data, to be allocated 85 * in the child device's parent_plat pointer. This value is only used as 86 * a fallback if this member is 0 in the driver. 87 * @ops: Uclass operations, providing the consistent interface to devices 88 * within the uclass. 89 * @flags: Flags for this uclass (DM_UC_...) 90 */ 91 struct uclass_driver { 92 const char *name; 93 enum uclass_id id; 94 int (*post_bind)(struct udevice *dev); 95 int (*pre_unbind)(struct udevice *dev); 96 int (*pre_probe)(struct udevice *dev); 97 int (*post_probe)(struct udevice *dev); 98 int (*pre_remove)(struct udevice *dev); 99 int (*child_post_bind)(struct udevice *dev); 100 int (*child_pre_probe)(struct udevice *dev); 101 int (*child_post_probe)(struct udevice *dev); 102 int (*init)(struct uclass *class); 103 int (*destroy)(struct uclass *class); 104 int priv_auto; 105 int per_device_auto; 106 int per_device_plat_auto; 107 int per_child_auto; 108 int per_child_plat_auto; 109 const void *ops; 110 uint32_t flags; 111 }; 112 113 /* Declare a new uclass_driver */ 114 #define UCLASS_DRIVER(__name) \ 115 ll_entry_declare(struct uclass_driver, __name, uclass_driver) 116 117 /** 118 * uclass_get_priv() - Get the private data for a uclass 119 * 120 * @uc Uclass to check 121 * @return private data, or NULL if none 122 */ 123 void *uclass_get_priv(const struct uclass *uc); 124 125 /** 126 * uclass_get() - Get a uclass based on an ID, creating it if needed 127 * 128 * Every uclass is identified by an ID, a number from 0 to n-1 where n is 129 * the number of uclasses. This function allows looking up a uclass by its 130 * ID. 131 * 132 * @key: ID to look up 133 * @ucp: Returns pointer to uclass (there is only one per ID) 134 * @return 0 if OK, -ve on error 135 */ 136 int uclass_get(enum uclass_id key, struct uclass **ucp); 137 138 /** 139 * uclass_get_name() - Get the name of a uclass driver 140 * 141 * @id: ID to look up 142 * @returns the name of the uclass driver for that ID, or NULL if none 143 */ 144 const char *uclass_get_name(enum uclass_id id); 145 146 /** 147 * uclass_get_by_name() - Look up a uclass by its driver name 148 * 149 * @name: Name to look up 150 * @returns the associated uclass ID, or UCLASS_INVALID if not found 151 */ 152 enum uclass_id uclass_get_by_name(const char *name); 153 154 /** 155 * uclass_get_device() - Get a uclass device based on an ID and index 156 * 157 * The device is probed to activate it ready for use. 158 * 159 * @id: ID to look up 160 * @index: Device number within that uclass (0=first) 161 * @devp: Returns pointer to device (there is only one per for each ID) 162 * @return 0 if OK, -ve on error 163 */ 164 int uclass_get_device(enum uclass_id id, int index, struct udevice **devp); 165 166 /** 167 * uclass_get_device_by_name() - Get a uclass device by its name 168 * 169 * This searches the devices in the uclass for one with the exactly given name. 170 * 171 * The device is probed to activate it ready for use. 172 * 173 * @id: ID to look up 174 * @name: name of a device to get 175 * @devp: Returns pointer to device (the first one with the name) 176 * @return 0 if OK, -ve on error 177 */ 178 int uclass_get_device_by_name(enum uclass_id id, const char *name, 179 struct udevice **devp); 180 181 /** 182 * uclass_get_device_by_seq() - Get a uclass device based on an ID and sequence 183 * 184 * If an active device has this sequence it will be returned. If there is no 185 * such device then this will check for a device that is requesting this 186 * sequence. 187 * 188 * The device is probed to activate it ready for use. 189 * 190 * @id: ID to look up 191 * @seq: Sequence number to find (0=first) 192 * @devp: Returns pointer to device (there is only one for each seq) 193 * @return 0 if OK, -ve on error 194 */ 195 int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp); 196 197 /** 198 * uclass_get_device_by_of_offset() - Get a uclass device by device tree node 199 * 200 * This searches the devices in the uclass for one attached to the given 201 * device tree node. 202 * 203 * The device is probed to activate it ready for use. 204 * 205 * @id: ID to look up 206 * @node: Device tree offset to search for (if -ve then -ENODEV is returned) 207 * @devp: Returns pointer to device (there is only one for each node) 208 * @return 0 if OK, -ve on error 209 */ 210 int uclass_get_device_by_of_offset(enum uclass_id id, int node, 211 struct udevice **devp); 212 213 /** 214 * uclass_get_device_by_ofnode() - Get a uclass device by device tree node 215 * 216 * This searches the devices in the uclass for one attached to the given 217 * device tree node. 218 * 219 * The device is probed to activate it ready for use. 220 * 221 * @id: ID to look up 222 * @np: Device tree node to search for (if NULL then -ENODEV is returned) 223 * @devp: Returns pointer to device (there is only one for each node) 224 * @return 0 if OK, -ve on error 225 */ 226 int uclass_get_device_by_ofnode(enum uclass_id id, ofnode node, 227 struct udevice **devp); 228 229 /** 230 * uclass_get_device_by_phandle_id() - Get a uclass device by phandle id 231 * 232 * This searches the devices in the uclass for one with the given phandle id. 233 * 234 * The device is probed to activate it ready for use. 235 * 236 * @id: uclass ID to look up 237 * @phandle_id: the phandle id to look up 238 * @devp: Returns pointer to device (there is only one for each node). NULL if 239 * there is no such device. 240 * @return 0 if OK, -ENODEV if there is no device match the phandle, other 241 * -ve on error 242 */ 243 int uclass_get_device_by_phandle_id(enum uclass_id id, uint phandle_id, 244 struct udevice **devp); 245 246 /** 247 * uclass_get_device_by_phandle() - Get a uclass device by phandle 248 * 249 * This searches the devices in the uclass for one with the given phandle. 250 * 251 * The device is probed to activate it ready for use. 252 * 253 * @id: uclass ID to look up 254 * @parent: Parent device containing the phandle pointer 255 * @name: Name of property in the parent device node 256 * @devp: Returns pointer to device (there is only one for each node) 257 * @return 0 if OK, -ENOENT if there is no @name present in the node, other 258 * -ve on error 259 */ 260 int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent, 261 const char *name, struct udevice **devp); 262 263 /** 264 * uclass_get_device_by_driver() - Get a uclass device for a driver 265 * 266 * This searches the devices in the uclass for one that uses the given 267 * driver. Use DM_DRIVER_GET(name) for the @drv argument, where 'name' is 268 * the driver name - as used in U_BOOT_DRIVER(name). 269 * 270 * The device is probed to activate it ready for use. 271 * 272 * @id: ID to look up 273 * @drv: Driver to look for 274 * @devp: Returns pointer to the first device with that driver 275 * @return 0 if OK, -ve on error 276 */ 277 int uclass_get_device_by_driver(enum uclass_id id, const struct driver *drv, 278 struct udevice **devp); 279 280 /** 281 * uclass_first_device() - Get the first device in a uclass 282 * 283 * The device returned is probed if necessary, and ready for use 284 * 285 * This function is useful to start iterating through a list of devices which 286 * are functioning correctly and can be probed. 287 * 288 * @id: Uclass ID to look up 289 * @devp: Returns pointer to the first device in that uclass if no error 290 * occurred, or NULL if there is no first device, or an error occurred with 291 * that device. 292 * @return 0 if OK (found or not found), other -ve on error 293 */ 294 int uclass_first_device(enum uclass_id id, struct udevice **devp); 295 296 /** 297 * uclass_first_device_err() - Get the first device in a uclass 298 * 299 * The device returned is probed if necessary, and ready for use 300 * 301 * @id: Uclass ID to look up 302 * @devp: Returns pointer to the first device in that uclass, or NULL if none 303 * @return 0 if found, -ENODEV if not found, other -ve on error 304 */ 305 int uclass_first_device_err(enum uclass_id id, struct udevice **devp); 306 307 /** 308 * uclass_next_device() - Get the next device in a uclass 309 * 310 * The device returned is probed if necessary, and ready for use 311 * 312 * This function is useful to iterate through a list of devices which 313 * are functioning correctly and can be probed. 314 * 315 * @devp: On entry, pointer to device to lookup. On exit, returns pointer 316 * to the next device in the uclass if no error occurred, or NULL if there is 317 * no next device, or an error occurred with that next device. 318 * @return 0 if OK (found or not found), other -ve on error 319 */ 320 int uclass_next_device(struct udevice **devp); 321 322 /** 323 * uclass_next_device_err() - Get the next device in a uclass 324 * 325 * The device returned is probed if necessary, and ready for use 326 * 327 * @devp: On entry, pointer to device to lookup. On exit, returns pointer 328 * to the next device in the uclass if no error occurred, or -ENODEV if 329 * there is no next device. 330 * @return 0 if found, -ENODEV if not found, other -ve on error 331 */ 332 int uclass_next_device_err(struct udevice **devp); 333 334 /** 335 * uclass_first_device_check() - Get the first device in a uclass 336 * 337 * The device returned is probed if necessary, and ready for use 338 * 339 * This function is useful to start iterating through a list of devices which 340 * are functioning correctly and can be probed. 341 * 342 * @id: Uclass ID to look up 343 * @devp: Returns pointer to the first device in that uclass, or NULL if there 344 * is no first device 345 * @return 0 if OK (found or not found), other -ve on error. If an error occurs 346 * it is still possible to move to the next device. 347 */ 348 int uclass_first_device_check(enum uclass_id id, struct udevice **devp); 349 350 /** 351 * uclass_next_device_check() - Get the next device in a uclass 352 * 353 * The device returned is probed if necessary, and ready for use 354 * 355 * This function is useful to start iterating through a list of devices which 356 * are functioning correctly and can be probed. 357 * 358 * @devp: On entry, pointer to device to lookup. On exit, returns pointer 359 * to the next device in the uclass if any 360 * @return 0 if OK (found or not found), other -ve on error. If an error occurs 361 * it is still possible to move to the next device. 362 */ 363 int uclass_next_device_check(struct udevice **devp); 364 365 /** 366 * uclass_first_device_drvdata() - Find the first device with given driver data 367 * 368 * This searches through the devices for a particular uclass looking for one 369 * that has the given driver data. 370 * 371 * @id: Uclass ID to check 372 * @driver_data: Driver data to search for 373 * @devp: Returns pointer to the first matching device in that uclass, if found 374 * @return 0 if found, -ENODEV if not found, other -ve on error 375 */ 376 int uclass_first_device_drvdata(enum uclass_id id, ulong driver_data, 377 struct udevice **devp); 378 379 /** 380 * uclass_probe_all() - Probe all devices based on an uclass ID 381 * 382 * This function probes all devices associated with a uclass by 383 * looking for its ID. 384 * 385 * @id: uclass ID to look up 386 * @return 0 if OK, other -ve on error 387 */ 388 int uclass_probe_all(enum uclass_id id); 389 390 /** 391 * uclass_id_foreach_dev() - Helper function to iteration through devices 392 * 393 * This creates a for() loop which works through the available devices in 394 * a uclass ID in order from start to end. 395 * 396 * If for some reason the uclass cannot be found, this does nothing. 397 * 398 * @id: enum uclass_id ID to use 399 * @pos: struct udevice * to hold the current device. Set to NULL when there 400 * are no more devices. 401 * @uc: temporary uclass variable (struct uclass *) 402 */ 403 #define uclass_id_foreach_dev(id, pos, uc) \ 404 if (!uclass_get(id, &uc)) \ 405 list_for_each_entry(pos, &uc->dev_head, uclass_node) 406 407 /** 408 * uclass_foreach_dev() - Helper function to iteration through devices 409 * 410 * This creates a for() loop which works through the available devices in 411 * a uclass in order from start to end. 412 * 413 * @pos: struct udevice * to hold the current device. Set to NULL when there 414 * are no more devices. 415 * @uc: uclass to scan 416 */ 417 #define uclass_foreach_dev(pos, uc) \ 418 list_for_each_entry(pos, &uc->dev_head, uclass_node) 419 420 /** 421 * uclass_foreach_dev_safe() - Helper function to safely iteration through devs 422 * 423 * This creates a for() loop which works through the available devices in 424 * a uclass in order from start to end. Inside the loop, it is safe to remove 425 * @pos if required. 426 * 427 * @pos: struct udevice * to hold the current device. Set to NULL when there 428 * are no more devices. 429 * @next: struct udevice * to hold the next next 430 * @uc: uclass to scan 431 */ 432 #define uclass_foreach_dev_safe(pos, next, uc) \ 433 list_for_each_entry_safe(pos, next, &uc->dev_head, uclass_node) 434 435 /** 436 * uclass_foreach_dev_probe() - Helper function to iteration through devices 437 * of given uclass 438 * 439 * This creates a for() loop which works through the available devices in 440 * a uclass in order from start to end. Devices are probed if necessary, 441 * and ready for use. 442 * 443 * @id: Uclass ID 444 * @dev: struct udevice * to hold the current device. Set to NULL when there 445 * are no more devices. 446 */ 447 #define uclass_foreach_dev_probe(id, dev) \ 448 for (int _ret = uclass_first_device_err(id, &dev); !_ret && dev; \ 449 _ret = uclass_next_device_err(&dev)) 450 451 #endif 452