u-boot/include/dm/device.h

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/*
* Copyright (c) 2013 Google, Inc
*
* (C) Copyright 2012
* Pavel Herrmann <morpheus.ibis@gmail.com>
* Marek Vasut <marex@denx.de>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef _DM_DEVICE_H
#define _DM_DEVICE_H
#include <dm/uclass-id.h>
#include <linker_lists.h>
#include <linux/list.h>
struct driver_info;
/* Driver is active (probed). Cleared when it is removed */
#define DM_FLAG_ACTIVATED (1 << 0)
/* DM is responsible for allocating and freeing platdata */
#define DM_FLAG_ALLOC_PDATA (1 << 1)
/**
* struct udevice - An instance of a driver
*
* This holds information about a device, which is a driver bound to a
* particular port or peripheral (essentially a driver instance).
*
* A device will come into existence through a 'bind' call, either due to
* a U_BOOT_DEVICE() macro (in which case platdata is non-NULL) or a node
* in the device tree (in which case of_offset is >= 0). In the latter case
* we translate the device tree information into platdata in a function
* implemented by the driver ofdata_to_platdata method (called just before the
* probe method if the device has a device tree node.
*
* All three of platdata, priv and uclass_priv can be allocated by the
* driver, or you can use the auto_alloc_size members of struct driver and
* struct uclass_driver to have driver model do this automatically.
*
* @driver: The driver used by this device
* @name: Name of device, typically the FDT node name
* @platdata: Configuration data for this device
* @of_offset: Device tree node offset for this device (- for none)
* @parent: Parent of this device, or NULL for the top level device
* @priv: Private data for this device
* @uclass: Pointer to uclass for this device
* @uclass_priv: The uclass's private data for this device
* @uclass_node: Used by uclass to link its devices
* @child_head: List of children of this device
* @sibling_node: Next device in list of all devices
* @flags: Flags for this device DM_FLAG_...
*/
struct udevice {
struct driver *driver;
const char *name;
void *platdata;
int of_offset;
struct udevice *parent;
void *priv;
struct uclass *uclass;
void *uclass_priv;
struct list_head uclass_node;
struct list_head child_head;
struct list_head sibling_node;
uint32_t flags;
};
/* Returns the operations for a device */
#define device_get_ops(dev) (dev->driver->ops)
/* Returns non-zero if the device is active (probed and not removed) */
#define device_active(dev) ((dev)->flags & DM_FLAG_ACTIVATED)
/**
* struct udevice_id - Lists the compatible strings supported by a driver
* @compatible: Compatible string
* @data: Data for this compatible string
*/
struct udevice_id {
const char *compatible;
ulong data;
};
/**
* struct driver - A driver for a feature or peripheral
*
* This holds methods for setting up a new device, and also removing it.
* The device needs information to set itself up - this is provided either
* by platdata or a device tree node (which we find by looking up
* matching compatible strings with of_match).
*
* Drivers all belong to a uclass, representing a class of devices of the
* same type. Common elements of the drivers can be implemented in the uclass,
* or the uclass can provide a consistent interface to the drivers within
* it.
*
* @name: Device name
* @id: Identiies the uclass we belong to
* @of_match: List of compatible strings to match, and any identifying data
* for each.
* @bind: Called to bind a device to its driver
* @probe: Called to probe a device, i.e. activate it
* @remove: Called to remove a device, i.e. de-activate it
* @unbind: Called to unbind a device from its driver
* @ofdata_to_platdata: Called before probe to decode device tree data
* @priv_auto_alloc_size: If non-zero this is the size of the private data
* to be allocated in the device's ->priv pointer. If zero, then the driver
* is responsible for allocating any data required.
* @platdata_auto_alloc_size: If non-zero this is the size of the
* platform data to be allocated in the device's ->platdata pointer.
* This is typically only useful for device-tree-aware drivers (those with
* an of_match), since drivers which use platdata will have the data
* provided in the U_BOOT_DEVICE() instantiation.
* ops: Driver-specific operations. This is typically a list of function
* pointers defined by the driver, to implement driver functions required by
* the uclass.
*/
struct driver {
char *name;
enum uclass_id id;
const struct udevice_id *of_match;
int (*bind)(struct udevice *dev);
int (*probe)(struct udevice *dev);
int (*remove)(struct udevice *dev);
int (*unbind)(struct udevice *dev);
int (*ofdata_to_platdata)(struct udevice *dev);
int priv_auto_alloc_size;
int platdata_auto_alloc_size;
const void *ops; /* driver-specific operations */
};
/* Declare a new U-Boot driver */
#define U_BOOT_DRIVER(__name) \
ll_entry_declare(struct driver, __name, driver)
/**
* dev_get_platdata() - Get the platform data for a device
*
* This checks that dev is not NULL, but no other checks for now
*
* @dev Device to check
* @return platform data, or NULL if none
*/
void *dev_get_platdata(struct udevice *dev);
/**
* dev_get_priv() - Get the private data for a device
*
* This checks that dev is not NULL, but no other checks for now
*
* @dev Device to check
* @return private data, or NULL if none
*/
void *dev_get_priv(struct udevice *dev);
#endif