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Diffstat (limited to 'include/dm/uclass.h')
| -rw-r--r-- | include/dm/uclass.h | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/include/dm/uclass.h b/include/dm/uclass.h new file mode 100644 index 0000000..484d166 --- /dev/null +++ b/include/dm/uclass.h @@ -0,0 +1,412 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2013 Google, Inc + * + * (C) Copyright 2012 + * Pavel Herrmann <morpheus.ibis@gmail.com> + */ + +#ifndef _DM_UCLASS_H +#define _DM_UCLASS_H + +#include <dm/ofnode.h> +#include <dm/uclass-id.h> +#include <linker_lists.h> +#include <linux/list.h> + +/** + * struct uclass - a U-Boot drive class, collecting together similar drivers + * + * A uclass provides an interface to a particular function, which is + * implemented by one or more drivers. Every driver belongs to a uclass even + * if it is the only driver in that uclass. An example uclass is GPIO, which + * provides the ability to change read inputs, set and clear outputs, etc. + * There may be drivers for on-chip SoC GPIO banks, I2C GPIO expanders and + * PMIC IO lines, all made available in a unified way through the uclass. + * + * @priv: Private data for this uclass + * @uc_drv: The driver for the uclass itself, not to be confused with a + * 'struct driver' + * @dev_head: List of devices in this uclass (devices are attached to their + * uclass when their bind method is called) + * @sibling_node: Next uclass in the linked list of uclasses + */ +struct uclass { + void *priv; + struct uclass_driver *uc_drv; + struct list_head dev_head; + struct list_head sibling_node; +}; + +struct driver; +struct udevice; + +/* Members of this uclass sequence themselves with aliases */ +#define DM_UC_FLAG_SEQ_ALIAS (1 << 0) + +/* Same as DM_FLAG_ALLOC_PRIV_DMA */ +#define DM_UC_FLAG_ALLOC_PRIV_DMA (1 << 5) + +/** + * struct uclass_driver - Driver for the uclass + * + * A uclass_driver provides a consistent interface to a set of related + * drivers. + * + * @name: Name of uclass driver + * @id: ID number of this uclass + * @post_bind: Called after a new device is bound to this uclass + * @pre_unbind: Called before a device is unbound from this uclass + * @pre_probe: Called before a new device is probed + * @post_probe: Called after a new device is probed + * @pre_remove: Called before a device is removed + * @child_post_bind: Called after a child is bound to a device in this uclass + * @child_pre_probe: Called before a child in this uclass is probed + * @child_post_probe: Called after a child in this uclass is probed + * @init: Called to set up the uclass + * @destroy: Called to destroy the uclass + * @priv_auto_alloc_size: If non-zero this is the size of the private data + * to be allocated in the uclass's ->priv pointer. If zero, then the uclass + * driver is responsible for allocating any data required. + * @per_device_auto_alloc_size: Each device can hold private data owned + * by the uclass. If required this will be automatically allocated if this + * value is non-zero. + * @per_device_platdata_auto_alloc_size: Each device can hold platform data + * owned by the uclass as 'dev->uclass_platdata'. If the value is non-zero, + * then this will be automatically allocated. + * @per_child_auto_alloc_size: Each child device (of a parent in this + * uclass) can hold parent data for the device/uclass. This value is only + * used as a fallback if this member is 0 in the driver. + * @per_child_platdata_auto_alloc_size: A bus likes to store information about + * its children. If non-zero this is the size of this data, to be allocated + * in the child device's parent_platdata pointer. This value is only used as + * a fallback if this member is 0 in the driver. + * @ops: Uclass operations, providing the consistent interface to devices + * within the uclass. + * @flags: Flags for this uclass (DM_UC_...) + */ +struct uclass_driver { + const char *name; + enum uclass_id id; + int (*post_bind)(struct udevice *dev); + int (*pre_unbind)(struct udevice *dev); + int (*pre_probe)(struct udevice *dev); + int (*post_probe)(struct udevice *dev); + int (*pre_remove)(struct udevice *dev); + int (*child_post_bind)(struct udevice *dev); + int (*child_pre_probe)(struct udevice *dev); + int (*child_post_probe)(struct udevice *dev); + int (*init)(struct uclass *class); + int (*destroy)(struct uclass *class); + int priv_auto_alloc_size; + int per_device_auto_alloc_size; + int per_device_platdata_auto_alloc_size; + int per_child_auto_alloc_size; + int per_child_platdata_auto_alloc_size; + const void *ops; + uint32_t flags; +}; + +/* Declare a new uclass_driver */ +#define UCLASS_DRIVER(__name) \ + ll_entry_declare(struct uclass_driver, __name, uclass) + +/** + * uclass_get() - Get a uclass based on an ID, creating it if needed + * + * Every uclass is identified by an ID, a number from 0 to n-1 where n is + * the number of uclasses. This function allows looking up a uclass by its + * ID. + * + * @key: ID to look up + * @ucp: Returns pointer to uclass (there is only one per ID) + * @return 0 if OK, -ve on error + */ +int uclass_get(enum uclass_id key, struct uclass **ucp); + +/** + * uclass_get_name() - Get the name of a uclass driver + * + * @id: ID to look up + * @returns the name of the uclass driver for that ID, or NULL if none + */ +const char *uclass_get_name(enum uclass_id id); + +/** + * uclass_get_by_name() - Look up a uclass by its driver name + * + * @name: Name to look up + * @returns the associated uclass ID, or UCLASS_INVALID if not found + */ +enum uclass_id uclass_get_by_name(const char *name); + +/** + * uclass_get_device() - Get a uclass device based on an ID and index + * + * The device is probed to activate it ready for use. + * + * @id: ID to look up + * @index: Device number within that uclass (0=first) + * @devp: Returns pointer to device (there is only one per for each ID) + * @return 0 if OK, -ve on error + */ +int uclass_get_device(enum uclass_id id, int index, struct udevice **devp); + +/** + * uclass_get_device_by_name() - Get a uclass device by its name + * + * This searches the devices in the uclass for one with the exactly given name. + * + * The device is probed to activate it ready for use. + * + * @id: ID to look up + * @name: name of a device to get + * @devp: Returns pointer to device (the first one with the name) + * @return 0 if OK, -ve on error + */ +int uclass_get_device_by_name(enum uclass_id id, const char *name, + struct udevice **devp); + +/** + * uclass_get_device_by_seq() - Get a uclass device based on an ID and sequence + * + * If an active device has this sequence it will be returned. If there is no + * such device then this will check for a device that is requesting this + * sequence. + * + * The device is probed to activate it ready for use. + * + * @id: ID to look up + * @seq: Sequence number to find (0=first) + * @devp: Returns pointer to device (there is only one for each seq) + * @return 0 if OK, -ve on error + */ +int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp); + +/** + * uclass_get_device_by_of_offset() - Get a uclass device by device tree node + * + * This searches the devices in the uclass for one attached to the given + * device tree node. + * + * The device is probed to activate it ready for use. + * + * @id: ID to look up + * @node: Device tree offset to search for (if -ve then -ENODEV is returned) + * @devp: Returns pointer to device (there is only one for each node) + * @return 0 if OK, -ve on error + */ +int uclass_get_device_by_of_offset(enum uclass_id id, int node, + struct udevice **devp); + +/** + * uclass_get_device_by_ofnode() - Get a uclass device by device tree node + * + * This searches the devices in the uclass for one attached to the given + * device tree node. + * + * The device is probed to activate it ready for use. + * + * @id: ID to look up + * @np: Device tree node to search for (if NULL then -ENODEV is returned) + * @devp: Returns pointer to device (there is only one for each node) + * @return 0 if OK, -ve on error + */ +int uclass_get_device_by_ofnode(enum uclass_id id, ofnode node, + struct udevice **devp); + +/** + * uclass_get_device_by_phandle_id() - Get a uclass device by phandle id + * + * This searches the devices in the uclass for one with the given phandle id. + * + * The device is probed to activate it ready for use. + * + * @id: uclass ID to look up + * @phandle_id: the phandle id to look up + * @devp: Returns pointer to device (there is only one for each node) + * @return 0 if OK, -ENODEV if there is no device match the phandle, other + * -ve on error + */ +int uclass_get_device_by_phandle_id(enum uclass_id id, uint phandle_id, + struct udevice **devp); + +/** + * uclass_get_device_by_phandle() - Get a uclass device by phandle + * + * This searches the devices in the uclass for one with the given phandle. + * + * The device is probed to activate it ready for use. + * + * @id: uclass ID to look up + * @parent: Parent device containing the phandle pointer + * @name: Name of property in the parent device node + * @devp: Returns pointer to device (there is only one for each node) + * @return 0 if OK, -ENOENT if there is no @name present in the node, other + * -ve on error + */ +int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent, + const char *name, struct udevice **devp); + +/** + * uclass_get_device_by_driver() - Get a uclass device for a driver + * + * This searches the devices in the uclass for one that uses the given + * driver. Use DM_GET_DRIVER(name) for the @drv argument, where 'name' is + * the driver name - as used in U_BOOT_DRIVER(name). + * + * The device is probed to activate it ready for use. + * + * @id: ID to look up + * @drv: Driver to look for + * @devp: Returns pointer to the first device with that driver + * @return 0 if OK, -ve on error + */ +int uclass_get_device_by_driver(enum uclass_id id, const struct driver *drv, + struct udevice **devp); + +/** + * uclass_first_device() - Get the first device in a uclass + * + * The device returned is probed if necessary, and ready for use + * + * This function is useful to start iterating through a list of devices which + * are functioning correctly and can be probed. + * + * @id: Uclass ID to look up + * @devp: Returns pointer to the first device in that uclass if no error + * occurred, or NULL if there is no first device, or an error occurred with + * that device. + * @return 0 if OK (found or not found), other -ve on error + */ +int uclass_first_device(enum uclass_id id, struct udevice **devp); + +/** + * uclass_first_device_err() - Get the first device in a uclass + * + * The device returned is probed if necessary, and ready for use + * + * @id: Uclass ID to look up + * @devp: Returns pointer to the first device in that uclass, or NULL if none + * @return 0 if found, -ENODEV if not found, other -ve on error + */ +int uclass_first_device_err(enum uclass_id id, struct udevice **devp); + +/** + * uclass_next_device() - Get the next device in a uclass + * + * The device returned is probed if necessary, and ready for use + * + * This function is useful to iterate through a list of devices which + * are functioning correctly and can be probed. + * + * @devp: On entry, pointer to device to lookup. On exit, returns pointer + * to the next device in the uclass if no error occurred, or NULL if there is + * no next device, or an error occurred with that next device. + * @return 0 if OK (found or not found), other -ve on error + */ +int uclass_next_device(struct udevice **devp); + +/** + * uclass_next_device_err() - Get the next device in a uclass + * + * The device returned is probed if necessary, and ready for use + * + * @devp: On entry, pointer to device to lookup. On exit, returns pointer + * to the next device in the uclass if no error occurred, or -ENODEV if + * there is no next device. + * @return 0 if found, -ENODEV if not found, other -ve on error + */ +int uclass_next_device_err(struct udevice **devp); + +/** + * uclass_first_device_check() - Get the first device in a uclass + * + * The device returned is probed if necessary, and ready for use + * + * This function is useful to start iterating through a list of devices which + * are functioning correctly and can be probed. + * + * @id: Uclass ID to look up + * @devp: Returns pointer to the first device in that uclass, or NULL if there + * is no first device + * @return 0 if OK (found or not found), other -ve on error. If an error occurs + * it is still possible to move to the next device. + */ +int uclass_first_device_check(enum uclass_id id, struct udevice **devp); + +/** + * uclass_next_device_check() - Get the next device in a uclass + * + * The device returned is probed if necessary, and ready for use + * + * This function is useful to start iterating through a list of devices which + * are functioning correctly and can be probed. + * + * @devp: On entry, pointer to device to lookup. On exit, returns pointer + * to the next device in the uclass if any + * @return 0 if OK (found or not found), other -ve on error. If an error occurs + * it is still possible to move to the next device. + */ +int uclass_next_device_check(struct udevice **devp); + +/** + * uclass_resolve_seq() - Resolve a device's sequence number + * + * On entry dev->seq is -1, and dev->req_seq may be -1 (to allocate a + * sequence number automatically, or >= 0 to select a particular number. + * If the requested sequence number is in use, then this device will + * be allocated another one. + * + * Note that the device's seq value is not changed by this function. + * + * @dev: Device for which to allocate sequence number + * @return sequence number allocated, or -ve on error + */ +int uclass_resolve_seq(struct udevice *dev); + +/** + * uclass_foreach_dev() - Helper function to iteration through devices + * + * This creates a for() loop which works through the available devices in + * a uclass in order from start to end. + * + * @pos: struct udevice * to hold the current device. Set to NULL when there + * are no more devices. + * @uc: uclass to scan + */ +#define uclass_foreach_dev(pos, uc) \ + list_for_each_entry(pos, &uc->dev_head, uclass_node) + +/** + * uclass_foreach_dev_safe() - Helper function to safely iteration through devs + * + * This creates a for() loop which works through the available devices in + * a uclass in order from start to end. Inside the loop, it is safe to remove + * @pos if required. + * + * @pos: struct udevice * to hold the current device. Set to NULL when there + * are no more devices. + * @next: struct udevice * to hold the next next + * @uc: uclass to scan + */ +#define uclass_foreach_dev_safe(pos, next, uc) \ + list_for_each_entry_safe(pos, next, &uc->dev_head, uclass_node) + +/** + * uclass_foreach_dev_probe() - Helper function to iteration through devices + * of given uclass + * + * This creates a for() loop which works through the available devices in + * a uclass in order from start to end. Devices are probed if necessary, + * and ready for use. + * + * @id: Uclass ID + * @dev: struct udevice * to hold the current device. Set to NULL when there + * are no more devices. + */ +#define uclass_foreach_dev_probe(id, dev) \ + for (int _ret = uclass_first_device_err(id, &dev); !_ret && dev; \ + _ret = uclass_next_device_err(&dev)) + +#endif |