2 * Copyright (c) 2013 Google, Inc
5 * Pavel Herrmann <morpheus.ibis@gmail.com>
6 * Marek Vasut <marex@denx.de>
8 * SPDX-License-Identifier: GPL-2.0+
14 #include <dm/uclass-id.h>
16 #include <linker_lists.h>
17 #include <linux/list.h>
21 /* Driver is active (probed). Cleared when it is removed */
22 #define DM_FLAG_ACTIVATED (1 << 0)
24 /* DM is responsible for allocating and freeing platdata */
25 #define DM_FLAG_ALLOC_PDATA (1 << 1)
27 /* DM should init this device prior to relocation */
28 #define DM_FLAG_PRE_RELOC (1 << 2)
30 /* DM is responsible for allocating and freeing parent_platdata */
31 #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
33 /* DM is responsible for allocating and freeing uclass_platdata */
34 #define DM_FLAG_ALLOC_UCLASS_PDATA (1 << 4)
36 /* Allocate driver private data on a DMA boundary */
37 #define DM_FLAG_ALLOC_PRIV_DMA (1 << 5)
40 #define DM_FLAG_BOUND (1 << 6)
43 * struct udevice - An instance of a driver
45 * This holds information about a device, which is a driver bound to a
46 * particular port or peripheral (essentially a driver instance).
48 * A device will come into existence through a 'bind' call, either due to
49 * a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node
50 * in the device tree (in which case of_offset is >= 0). In the latter case
51 * we translate the device tree information into platdata in a function
52 * implemented by the driver ofdata_to_platdata method (called just before the
53 * probe method if the device has a device tree node.
55 * All three of platdata, priv and uclass_priv can be allocated by the
56 * driver, or you can use the auto_alloc_size members of struct driver and
57 * struct uclass_driver to have driver model do this automatically.
59 * @driver: The driver used by this device
60 * @name: Name of device, typically the FDT node name
61 * @platdata: Configuration data for this device
62 * @parent_platdata: The parent bus's configuration data for this device
63 * @uclass_platdata: The uclass's configuration data for this device
64 * @of_offset: Device tree node offset for this device (- for none)
65 * @driver_data: Driver data word for the entry that matched this device with
67 * @parent: Parent of this device, or NULL for the top level device
68 * @priv: Private data for this device
69 * @uclass: Pointer to uclass for this device
70 * @uclass_priv: The uclass's private data for this device
71 * @parent_priv: The parent's private data for this device
72 * @uclass_node: Used by uclass to link its devices
73 * @child_head: List of children of this device
74 * @sibling_node: Next device in list of all devices
75 * @flags: Flags for this device DM_FLAG_...
76 * @req_seq: Requested sequence number for this device (-1 = any)
77 * @seq: Allocated sequence number for this device (-1 = none). This is set up
78 * when the device is probed and will be unique within the device's uclass.
81 const struct driver *driver;
84 void *parent_platdata;
85 void *uclass_platdata;
88 struct udevice *parent;
90 struct uclass *uclass;
93 struct list_head uclass_node;
94 struct list_head child_head;
95 struct list_head sibling_node;
101 /* Maximum sequence number supported */
102 #define DM_MAX_SEQ 999
104 /* Returns the operations for a device */
105 #define device_get_ops(dev) (dev->driver->ops)
107 /* Returns non-zero if the device is active (probed and not removed) */
108 #define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED)
111 * struct udevice_id - Lists the compatible strings supported by a driver
112 * @compatible: Compatible string
113 * @data: Data for this compatible string
116 const char *compatible;
120 #ifdef CONFIG_OF_CONTROL
121 #define of_match_ptr(_ptr) (_ptr)
123 #define of_match_ptr(_ptr) NULL
124 #endif /* CONFIG_OF_CONTROL */
127 * struct driver - A driver for a feature or peripheral
129 * This holds methods for setting up a new device, and also removing it.
130 * The device needs information to set itself up - this is provided either
131 * by platdata or a device tree node (which we find by looking up
132 * matching compatible strings with of_match).
134 * Drivers all belong to a uclass, representing a class of devices of the
135 * same type. Common elements of the drivers can be implemented in the uclass,
136 * or the uclass can provide a consistent interface to the drivers within
140 * @id: Identiies the uclass we belong to
141 * @of_match: List of compatible strings to match, and any identifying data
143 * @bind: Called to bind a device to its driver
144 * @probe: Called to probe a device, i.e. activate it
145 * @remove: Called to remove a device, i.e. de-activate it
146 * @unbind: Called to unbind a device from its driver
147 * @ofdata_to_platdata: Called before probe to decode device tree data
148 * @child_post_bind: Called after a new child has been bound
149 * @child_pre_probe: Called before a child device is probed. The device has
150 * memory allocated but it has not yet been probed.
151 * @child_post_remove: Called after a child device is removed. The device
152 * has memory allocated but its device_remove() method has been called.
153 * @priv_auto_alloc_size: If non-zero this is the size of the private data
154 * to be allocated in the device's ->priv pointer. If zero, then the driver
155 * is responsible for allocating any data required.
156 * @platdata_auto_alloc_size: If non-zero this is the size of the
157 * platform data to be allocated in the device's ->platdata pointer.
158 * This is typically only useful for device-tree-aware drivers (those with
159 * an of_match), since drivers which use platdata will have the data
160 * provided in the U_BOOT_DEVICE() instantiation.
161 * @per_child_auto_alloc_size: Each device can hold private data owned by
162 * its parent. If required this will be automatically allocated if this
164 * TODO(sjg@chromium.org): I'm considering dropping this, and just having
165 * device_probe_child() pass it in. So far the use case for allocating it
166 * is SPI, but I found that unsatisfactory. Since it is here I will leave it
167 * until things are clearer.
168 * @per_child_platdata_auto_alloc_size: A bus likes to store information about
169 * its children. If non-zero this is the size of this data, to be allocated
170 * in the child's parent_platdata pointer.
171 * @ops: Driver-specific operations. This is typically a list of function
172 * pointers defined by the driver, to implement driver functions required by
174 * @flags: driver flags - see DM_FLAGS_...
179 const struct udevice_id *of_match;
180 int (*bind)(struct udevice *dev);
181 int (*probe)(struct udevice *dev);
182 int (*remove)(struct udevice *dev);
183 int (*unbind)(struct udevice *dev);
184 int (*ofdata_to_platdata)(struct udevice *dev);
185 int (*child_post_bind)(struct udevice *dev);
186 int (*child_pre_probe)(struct udevice *dev);
187 int (*child_post_remove)(struct udevice *dev);
188 int priv_auto_alloc_size;
189 int platdata_auto_alloc_size;
190 int per_child_auto_alloc_size;
191 int per_child_platdata_auto_alloc_size;
192 const void *ops; /* driver-specific operations */
196 /* Declare a new U-Boot driver */
197 #define U_BOOT_DRIVER(__name) \
198 ll_entry_declare(struct driver, __name, driver)
201 * dev_get_platdata() - Get the platform data for a device
203 * This checks that dev is not NULL, but no other checks for now
205 * @dev Device to check
206 * @return platform data, or NULL if none
208 void *dev_get_platdata(struct udevice *dev);
211 * dev_get_parent_platdata() - Get the parent platform data for a device
213 * This checks that dev is not NULL, but no other checks for now
215 * @dev Device to check
216 * @return parent's platform data, or NULL if none
218 void *dev_get_parent_platdata(struct udevice *dev);
221 * dev_get_uclass_platdata() - Get the uclass platform data for a device
223 * This checks that dev is not NULL, but no other checks for now
225 * @dev Device to check
226 * @return uclass's platform data, or NULL if none
228 void *dev_get_uclass_platdata(struct udevice *dev);
231 * dev_get_parentdata() - Get the parent data for a device
233 * The parent data is data stored in the device but owned by the parent.
234 * For example, a USB device may have parent data which contains information
235 * about how to talk to the device over USB.
237 * This checks that dev is not NULL, but no other checks for now
239 * @dev Device to check
240 * @return parent data, or NULL if none
242 void *dev_get_parentdata(struct udevice *dev);
245 * dev_get_priv() - Get the private data for a device
247 * This checks that dev is not NULL, but no other checks for now
249 * @dev Device to check
250 * @return private data, or NULL if none
252 void *dev_get_priv(struct udevice *dev);
255 * struct dev_get_parent() - Get the parent of a device
257 * @child: Child to check
258 * @return parent of child, or NULL if this is the root device
260 struct udevice *dev_get_parent(struct udevice *child);
263 * dev_get_uclass_priv() - Get the private uclass data for a device
265 * This checks that dev is not NULL, but no other checks for now
267 * @dev Device to check
268 * @return private uclass data for this device, or NULL if none
270 void *dev_get_uclass_priv(struct udevice *dev);
273 * dev_get_driver_data() - get the driver data used to bind a device
275 * When a device is bound using a device tree node, it matches a
276 * particular compatible string as in struct udevice_id. This function
277 * returns the associated data value for that compatible string. This is
278 * the 'data' field in struct udevice_id.
280 * For USB devices, this is the driver_info field in struct usb_device_id.
282 * @dev: Device to check
284 ulong dev_get_driver_data(struct udevice *dev);
287 * dev_get_driver_ops() - get the device's driver's operations
289 * This checks that dev is not NULL, and returns the pointer to device's
290 * driver's operations.
292 * @dev: Device to check
293 * @return void pointer to driver's operations or NULL for NULL-dev or NULL-ops
295 const void *dev_get_driver_ops(struct udevice *dev);
298 * device_get_uclass_id() - return the uclass ID of a device
300 * @dev: Device to check
301 * @return uclass ID for the device
303 enum uclass_id device_get_uclass_id(struct udevice *dev);
306 * dev_get_uclass_name() - return the uclass name of a device
308 * This checks that dev is not NULL.
310 * @dev: Device to check
311 * @return pointer to the uclass name for the device
313 const char *dev_get_uclass_name(struct udevice *dev);
316 * device_get_child() - Get the child of a device by index
318 * Returns the numbered child, 0 being the first. This does not use
319 * sequence numbers, only the natural order.
321 * @dev: Parent device to check
322 * @index: Child index
323 * @devp: Returns pointer to device
324 * @return 0 if OK, -ENODEV if no such device, other error if the device fails
327 int device_get_child(struct udevice *parent, int index, struct udevice **devp);
330 * device_find_child_by_seq() - Find a child device based on a sequence
332 * This searches for a device with the given seq or req_seq.
334 * For seq, if an active device has this sequence it will be returned.
335 * If there is no such device then this will return -ENODEV.
337 * For req_seq, if a device (whether activated or not) has this req_seq
338 * value, that device will be returned. This is a strong indication that
339 * the device will receive that sequence when activated.
341 * @parent: Parent device
342 * @seq_or_req_seq: Sequence number to find (0=first)
343 * @find_req_seq: true to find req_seq, false to find seq
344 * @devp: Returns pointer to device (there is only one per for each seq).
345 * Set to NULL if none is found
346 * @return 0 if OK, -ve on error
348 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq,
349 bool find_req_seq, struct udevice **devp);
352 * device_get_child_by_seq() - Get a child device based on a sequence
354 * If an active device has this sequence it will be returned. If there is no
355 * such device then this will check for a device that is requesting this
358 * The device is probed to activate it ready for use.
360 * @parent: Parent device
361 * @seq: Sequence number to find (0=first)
362 * @devp: Returns pointer to device (there is only one per for each seq)
363 * Set to NULL if none is found
364 * @return 0 if OK, -ve on error
366 int device_get_child_by_seq(struct udevice *parent, int seq,
367 struct udevice **devp);
370 * device_find_child_by_of_offset() - Find a child device based on FDT offset
372 * Locates a child device by its device tree offset.
374 * @parent: Parent device
375 * @of_offset: Device tree offset to find
376 * @devp: Returns pointer to device if found, otherwise this is set to NULL
377 * @return 0 if OK, -ve on error
379 int device_find_child_by_of_offset(struct udevice *parent, int of_offset,
380 struct udevice **devp);
383 * device_get_child_by_of_offset() - Get a child device based on FDT offset
385 * Locates a child device by its device tree offset.
387 * The device is probed to activate it ready for use.
389 * @parent: Parent device
390 * @of_offset: Device tree offset to find
391 * @devp: Returns pointer to device if found, otherwise this is set to NULL
392 * @return 0 if OK, -ve on error
394 int device_get_child_by_of_offset(struct udevice *parent, int of_offset,
395 struct udevice **devp);
398 * device_get_global_by_of_offset() - Get a device based on FDT offset
400 * Locates a device by its device tree offset, searching globally throughout
401 * the all driver model devices.
403 * The device is probed to activate it ready for use.
405 * @of_offset: Device tree offset to find
406 * @devp: Returns pointer to device if found, otherwise this is set to NULL
407 * @return 0 if OK, -ve on error
409 int device_get_global_by_of_offset(int of_offset, struct udevice **devp);
412 * device_find_first_child() - Find the first child of a device
414 * @parent: Parent device to search
415 * @devp: Returns first child device, or NULL if none
418 int device_find_first_child(struct udevice *parent, struct udevice **devp);
421 * device_find_next_child() - Find the next child of a device
423 * @devp: Pointer to previous child device on entry. Returns pointer to next
424 * child device, or NULL if none
427 int device_find_next_child(struct udevice **devp);
430 * dev_get_addr() - Get the reg property of a device
432 * @dev: Pointer to a device
436 fdt_addr_t dev_get_addr(struct udevice *dev);
439 * device_has_children() - check if a device has any children
441 * @dev: Device to check
442 * @return true if the device has one or more children
444 bool device_has_children(struct udevice *dev);
447 * device_has_active_children() - check if a device has any active children
449 * @dev: Device to check
450 * @return true if the device has one or more children and at least one of
451 * them is active (probed).
453 bool device_has_active_children(struct udevice *dev);
456 * device_is_last_sibling() - check if a device is the last sibling
458 * This function can be useful for display purposes, when special action needs
459 * to be taken when displaying the last sibling. This can happen when a tree
460 * view of devices is being displayed.
462 * @dev: Device to check
463 * @return true if there are no more siblings after this one - i.e. is it
466 bool device_is_last_sibling(struct udevice *dev);