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