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