u-boot-brain/include/dm/device-internal.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_INTERNAL_H
#define _DM_DEVICE_INTERNAL_H
struct udevice;
/**
* device_bind() - Create a device and bind it to a driver
*
* Called to set up a new device attached to a driver. The device will either
* have platdata, or a device tree node which can be used to create the
* platdata.
*
* Once bound a device exists but is not yet active until device_probe() is
* called.
*
* @parent: Pointer to device's parent, under which this driver will exist
* @drv: Device's driver
* @name: Name of device (e.g. device tree node name)
* @platdata: Pointer to data for this device - the structure is device-
* specific but may include the device's I/O address, etc.. This is NULL for
* devices which use device tree.
* @of_offset: Offset of device tree node for this device. This is -1 for
* devices which don't use device tree.
* @devp: Returns a pointer to the bound device
* @return 0 if OK, -ve on error
*/
int device_bind(struct udevice *parent, const struct driver *drv,
const char *name, void *platdata, int of_offset,
struct udevice **devp);
/**
* device_bind_by_name: Create a device and bind it to a driver
*
* This is a helper function used to bind devices which do not use device
* tree.
*
* @parent: Pointer to device's parent
* @pre_reloc_only: If true, bind the driver only if its DM_INIT_F flag is set.
* If false bind the driver always.
* @info: Name and platdata for this device
* @devp: Returns a pointer to the bound device
* @return 0 if OK, -ve on error
*/
int device_bind_by_name(struct udevice *parent, bool pre_reloc_only,
const struct driver_info *info, struct udevice **devp);
/**
* device_probe() - Probe a device, activating it
*
* Activate a device so that it is ready for use. All its parents are probed
* first.
*
* @dev: Pointer to device to probe
* @return 0 if OK, -ve on error
*/
int device_probe(struct udevice *dev);
/**
* device_probe() - Probe a child device, activating it
*
* Activate a device so that it is ready for use. All its parents are probed
* first. The child is provided with parent data if parent_priv is not NULL.
*
* @dev: Pointer to device to probe
* @parent_priv: Pointer to parent data. If non-NULL then this is provided to
* the child.
* @return 0 if OK, -ve on error
*/
int device_probe_child(struct udevice *dev, void *parent_priv);
/**
* device_remove() - Remove a device, de-activating it
*
* De-activate a device so that it is no longer ready for use. All its
* children are deactivated first.
*
* @dev: Pointer to device to remove
* @return 0 if OK, -ve on error (an error here is normally a very bad thing)
*/
#ifdef CONFIG_DM_DEVICE_REMOVE
int device_remove(struct udevice *dev);
#else
static inline int device_remove(struct udevice *dev) { return 0; }
#endif
/**
* device_unbind() - Unbind a device, destroying it
*
* Unbind a device and remove all memory used by it
*
* @dev: Pointer to device to unbind
* @return 0 if OK, -ve on error
*/
#ifdef CONFIG_DM_DEVICE_REMOVE
int device_unbind(struct udevice *dev);
#else
static inline int device_unbind(struct udevice *dev) { return 0; }
#endif
/**
* device_remove_children() - Stop all device's children
* @dev: The device whose children are to be removed
* @return 0 on success, -ve on error
*/
#ifdef CONFIG_DM_DEVICE_REMOVE
int device_remove_children(struct udevice *dev);
#else
static inline int device_remove_children(struct udevice *dev) { return 0; }
#endif
/**
* device_unbind_children() - Unbind all device's children from the device
*
* On error, the function continues to unbind all children, and reports the
* first error.
*
* @dev: The device that is to be stripped of its children
* @return 0 on success, -ve on error
*/
#ifdef CONFIG_DM_DEVICE_REMOVE
int device_unbind_children(struct udevice *dev);
#else
static inline int device_unbind_children(struct udevice *dev) { return 0; }
#endif
#ifdef CONFIG_DM_DEVICE_REMOVE
void device_free(struct udevice *dev);
#else
static inline void device_free(struct udevice *dev) {}
#endif
/**
* simple_bus_translate() - translate a bus address to a system address
*
* This handles the 'ranges' property in a simple bus. It translates the
* device address @addr to a system address using this property.
*
* @dev: Simple bus device (parent of target device)
* @addr: Address to translate
* @return new address
*/
fdt_addr_t simple_bus_translate(struct udevice *dev, fdt_addr_t addr);
/* Cast away any volatile pointer */
#define DM_ROOT_NON_CONST (((gd_t *)gd)->dm_root)
#define DM_UCLASS_ROOT_NON_CONST (((gd_t *)gd)->uclass_root)
devres: introduce Devres (Managed Device Resource) framework In U-Boot's driver model, memory is basically allocated and freed in the core framework. So, low level drivers generally only have to specify the size of needed memory with .priv_auto_alloc_size, .platdata_auto_alloc_size, etc. Nevertheless, some drivers still need to allocate/free memory on their own in case they cannot statically know the necessary memory size. So, I believe it is reasonable enough to port Devres into U-boot. Devres, which originates in Linux, manages device resources for each device and automatically releases them on driver detach. With devres, device resources are guaranteed to be freed whether initialization fails half-way or the device gets detached. The basic idea is totally the same to that of Linux, but I tweaked it a bit so that it fits in U-Boot's driver model. In U-Boot, drivers are activated in two steps: binding and probing. Binding puts a driver and a device together. It is just data manipulation on the system memory, so nothing has happened on the hardware device at this moment. When the device is really used, it is probed. Probing initializes the real hardware device to make it really ready for use. So, the resources acquired during the probing process must be freed when the device is removed. Likewise, what has been allocated in binding should be released when the device is unbound. The struct devres has a member "probe" to remember when the resource was allocated. CONFIG_DEBUG_DEVRES is also supported for easier debugging. If enabled, debug messages are printed each time a resource is allocated/freed. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Simon Glass <sjg@chromium.org>
2015-07-25 21:52:35 +09:00
/* device resource management */
/**
* devres_release_probe - Release managed resources allocated after probing
* @dev: Device to release resources for
*
* Release all resources allocated for @dev when it was probed or later.
* This function is called on driver removal.
*/
void devres_release_probe(struct udevice *dev);
/**
* devres_release_all - Release all managed resources
* @dev: Device to release resources for
*
* Release all resources associated with @dev. This function is
* called on driver unbinding.
*/
void devres_release_all(struct udevice *dev);
#endif