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linux-stable/include/linux/fwnode.h

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driver core / ACPI: Represent ACPI companions using fwnode_handle Now that we have struct fwnode_handle, we can use that to point to ACPI companions from struct device objects instead of pointing to struct acpi_device directly. There are two benefits from that. First, the somewhat ugly and hackish struct acpi_dev_node can be dropped and, second, the same struct fwnode_handle pointer can be used in the future to point to other (non-ACPI) firmware device node types. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-16 22:49:03 +00:00
/*
* fwnode.h - Firmware device node object handle type definition.
*
* Copyright (C) 2015, Intel Corporation
* Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _LINUX_FWNODE_H_
#define _LINUX_FWNODE_H_
enum fwnode_type {
FWNODE_INVALID = 0,
FWNODE_OF,
FWNODE_ACPI,
ACPI / property: Add support for data-only subnodes In some cases, the information expressed via device properties is hierarchical by nature. For example, the properties of a composite device consisting of multiple semi-dependent components may need to be represented in the form of a tree of property data sets corresponding to specific components of the device. Unfortunately, using ACPI device objects for this purpose turns out to be problematic, mostly due to the assumption made by some operating systems (that platform firmware generally needs to work with) that each device object in the ACPI namespace represents a device requiring a separate driver. That assumption leads to complications which reportedly are impractically difficult to overcome and a different approach is needed for the sake of interoperability. The approach implemented here is based on extending _DSD via pointers (links) to additional ACPI objects returning data packages formatted in accordance with the _DSD formatting rules defined by Section 6.2.5 of ACPI 6. Those additional objects are referred to as data-only subnodes of the device object containing the _DSD pointing to them. The links to them need to be located in a separate section of the _DSD data package following UUID dbb8e3e6-5886-4ba6-8795-1319f52a966b referred to as the Hierarchical Data Extension UUID as defined in [1]. Each of them is represented by a package of two strings. The first string in that package (the key) is regarded as the name of the data-only subnode pointed to by the link. The second string in it (the target) is expected to hold the ACPI namespace path (possibly utilizing the usual ACPI namespace search rules) of an ACPI object evaluating to a data package extending the _DSD. The device properties initialization code follows those links, creates a struct acpi_data_node object for each of them to store the data returned by the ACPI object pointed to by it and processes those data recursively (which may lead to the creation of more struct acpi_data_node objects if the returned data package contains the Hierarchical Data Extension UUID section with more links in it). All of the struct acpi_data_node objects are present until the the ACPI device object containing the _DSD with links to them is deleted and they are deleted along with that object. [1]: http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.pdf Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2015-08-27 02:36:14 +00:00
FWNODE_ACPI_DATA,
ACPI: Add FWNODE_ACPI_STATIC fwnode type On systems booting with a device tree, every struct device is associated with a struct device_node, that provides its DT firmware representation. The device node can be used in generic kernel contexts (eg IRQ translation, IOMMU streamid mapping), to retrieve the properties associated with the device and carry out kernel operations accordingly. Owing to the 1:1 relationship between the device and its device_node, the device_node can also be used as a look-up token for the device (eg looking up a device through its device_node), to retrieve the device in kernel paths where the device_node is available. On systems booting with ACPI, the same abstraction provided by the device_node is required to provide look-up functionality. The struct acpi_device, that represents firmware objects in the ACPI namespace already includes a struct fwnode_handle of type FWNODE_ACPI as their member; the same abstraction is missing though for devices that are instantiated out of static ACPI tables entries (eg ARM SMMU devices). Add a new fwnode_handle type to associate devices created out of static ACPI table entries to the respective firmware components and create a simple ACPI core layer interface to dynamically allocate and free the corresponding firmware nodes so that kernel subsystems can use it to instantiate the nodes and associate them with the respective devices. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Tomasz Nowicki <tn@semihalf.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Tomasz Nowicki <tn@semihalf.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-21 10:01:33 +00:00
FWNODE_ACPI_STATIC,
device property: Introduce firmware node type for platform data Introduce data structures and code allowing "built-in" properties to be associated with devices in such a way that they will be used by the device_property_* API if no proper firmware node (neither DT nor ACPI) is present for the given device. Each property is to be represented by a property_entry structure. An array of property_entry structures (terminated with a null entry) can be pointed to by the properties field of struct property_set that can be added as a firmware node to a struct device using device_add_property_set(). That will cause the device_property_* API to use that property_set as the source of properties if the given device does not have a DT node or an ACPI companion device object associated with it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-03 14:05:11 +00:00
FWNODE_PDATA,
ACPI: Add FWNODE_ACPI_STATIC fwnode type On systems booting with a device tree, every struct device is associated with a struct device_node, that provides its DT firmware representation. The device node can be used in generic kernel contexts (eg IRQ translation, IOMMU streamid mapping), to retrieve the properties associated with the device and carry out kernel operations accordingly. Owing to the 1:1 relationship between the device and its device_node, the device_node can also be used as a look-up token for the device (eg looking up a device through its device_node), to retrieve the device in kernel paths where the device_node is available. On systems booting with ACPI, the same abstraction provided by the device_node is required to provide look-up functionality. The struct acpi_device, that represents firmware objects in the ACPI namespace already includes a struct fwnode_handle of type FWNODE_ACPI as their member; the same abstraction is missing though for devices that are instantiated out of static ACPI tables entries (eg ARM SMMU devices). Add a new fwnode_handle type to associate devices created out of static ACPI table entries to the respective firmware components and create a simple ACPI core layer interface to dynamically allocate and free the corresponding firmware nodes so that kernel subsystems can use it to instantiate the nodes and associate them with the respective devices. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Tomasz Nowicki <tn@semihalf.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Tomasz Nowicki <tn@semihalf.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-21 10:01:33 +00:00
FWNODE_IRQCHIP
driver core / ACPI: Represent ACPI companions using fwnode_handle Now that we have struct fwnode_handle, we can use that to point to ACPI companions from struct device objects instead of pointing to struct acpi_device directly. There are two benefits from that. First, the somewhat ugly and hackish struct acpi_dev_node can be dropped and, second, the same struct fwnode_handle pointer can be used in the future to point to other (non-ACPI) firmware device node types. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-16 22:49:03 +00:00
};
struct fwnode_handle {
enum fwnode_type type;
device property: Make it possible to use secondary firmware nodes Add a secondary pointer to struct fwnode_handle so as to make it possible for a device to have two firmware nodes associated with it at the same time, for example, an ACPI node and a node with a set of properties provided by platform initialization code. In the future that will allow device property lookup to fall back from the primary firmware node to the secondary one if the given property is not present there to make it easier to provide defaults for device properties used by device drivers. Introduce two helper routines, set_primary_fwnode() and set_secondary_fwnode() allowing callers to add a primary/secondary firmware node to the given device in such a way that (1) If there's only one firmware node for that device, it will be pointed to by the device's firmware node pointer. (2) If both the primary and secondary firmware nodes are present, the primary one will be pointed to by the device's firmware node pointer, while the secondary one will be pointed to by the primary node's secondary pointer. (3) If one of these nodes is removed (by calling one of the new nelpers with NULL as the second argument), the other one will be preserved. Make ACPI use set_primary_fwnode() for attaching its firmware nodes to devices. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-03 21:23:37 +00:00
struct fwnode_handle *secondary;
driver core / ACPI: Represent ACPI companions using fwnode_handle Now that we have struct fwnode_handle, we can use that to point to ACPI companions from struct device objects instead of pointing to struct acpi_device directly. There are two benefits from that. First, the somewhat ugly and hackish struct acpi_dev_node can be dropped and, second, the same struct fwnode_handle pointer can be used in the future to point to other (non-ACPI) firmware device node types. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-16 22:49:03 +00:00
};
#endif
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