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path: root/drivers/acpi/property.c
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* device property: attach 'else if' to the proper 'if'Andy Shevchenko2015-08-261-2/+3
| | | | | | | | | | | Obviously in the current place the 'else' keyword is redundant, though it seems quite correct when we check if nval is in allowed range. Reattach the condition branch there. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / property: Define a symbol for PRP0001Rafael J. Wysocki2015-05-221-4/+4
| | | | | | | | | Use a #defined symbol ACPI_DT_NAMESPACE_HID instead of the PRP0001 string. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
* ACPI / property: Refine consistency check for PRP0001Rafael J. Wysocki2015-05-051-23/+31
| | | | | | | | | | | | | | | | | | | | | | | Refine the check for the presence of the "compatible" property if the PRP0001 device ID is present in the device's list of ACPI/PNP IDs to also print the message if _DSD is missing entirely or the format of it is incorrect. One special case to take into accout is that the "compatible" property need not be provided for devices having the PRP0001 device ID in their lists of ACPI/PNP IDs if they are ancestors of PRP0001 devices with the "compatible" property present. This is to cover heriarchies of device objects where the kernel is only supposed to use a struct device representation for the topmost one and the others represent, for example, functional blocks of a composite device. While at it, reduce the log level of the message to "info" and reduce the log level of the "broken _DSD" message to "debug" (noise reduction). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
* ACPI / property: Drop size_prop from acpi_dev_get_property_reference()Rafael J. Wysocki2014-11-051-46/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | The size_prop argument of the recently added function acpi_dev_get_property_reference() is not used by the only current caller of that function and is very unlikely to be used at any time going forward. Namely, for a property whose value is a list of items each containing a references to a device object possibly accompanied by some integers, the number of items in the list can always be computed as the number of elements of type ACPI_TYPE_LOCAL_REFERENCE in the property package. Thus it should never be necessary to provide an additional "cells" property with a value equal to the number of items in that list. It also should never be necessary to provide a "cells" property specifying how many integers are supposed to be following each reference. For this reason, drop the size_prop argument from acpi_dev_get_property_reference() and update its caller accordingly. Link: http://marc.info/?l=linux-kernel&m=141511255610556&w=2 Suggested-by: Grant Likely <grant.likely@linaro.org> Acked-by: Grant Likely <grant.likely@linaro.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: Allow drivers to match using Device Tree compatible propertyMika Westerberg2014-11-041-0/+39
| | | | | | | | | | | | | | | We have lots of existing Device Tree enabled drivers and allocating separate _HID for each is not feasible. Instead we allocate special _HID "PRP0001" that means that the match should be done using Device Tree compatible property using driver's .of_match_table instead if the driver is missing .acpi_match_table. If there is a need to distinguish from where the device is enumerated (DT/ACPI) driver can check dev->of_node or ACPI_COMPATION(dev). Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Driver core: Unified device properties interface for platform firmwareRafael J. Wysocki2014-11-041-0/+178
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a uniform interface by which device drivers can request device properties from the platform firmware by providing a property name and the corresponding data type. The purpose of it is to help to write portable code that won't depend on any particular platform firmware interface. The following general helper functions are added: device_property_present() device_property_read_u8() device_property_read_u16() device_property_read_u32() device_property_read_u64() device_property_read_string() device_property_read_u8_array() device_property_read_u16_array() device_property_read_u32_array() device_property_read_u64_array() device_property_read_string_array() The first one allows the caller to check if the given property is present. The next 5 of them allow single-valued properties of various types to be retrieved in a uniform way. The remaining 5 are for reading properties with multiple values (arrays of either numbers or strings). The interface covers both ACPI and Device Trees. This change set includes material from Mika Westerberg and Aaron Lu. Signed-off-by: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: Add support for device specific propertiesMika Westerberg2014-11-041-0/+364
Device Tree is used in many embedded systems to describe the system configuration to the OS. It supports attaching properties or name-value pairs to the devices it describe. With these properties one can pass additional information to the drivers that would not be available otherwise. ACPI is another configuration mechanism (among other things) typically seen, but not limited to, x86 machines. ACPI allows passing arbitrary data from methods but there has not been mechanism equivalent to Device Tree until the introduction of _DSD in the recent publication of the ACPI 5.1 specification. In order to facilitate ACPI usage in systems where Device Tree is typically used, it would be beneficial to standardize a way to retrieve Device Tree style properties from ACPI devices, which is what we do in this patch. If a given device described in ACPI namespace wants to export properties it must implement _DSD method (Device Specific Data, introduced with ACPI 5.1) that returns the properties in a package of packages. For example: Name (_DSD, Package () { ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), Package () { Package () {"name1", <VALUE1>}, Package () {"name2", <VALUE2>}, ... } }) The UUID reserved for properties is daffd814-6eba-4d8c-8a91-bc9bbf4aa301 and is documented in the ACPI 5.1 companion document called "_DSD Implementation Guide" [1], [2]. We add several helper functions that can be used to extract these properties and convert them to different Linux data types. The ultimate goal is that we only have one device property API that retrieves the requested properties from Device Tree or from ACPI transparent to the caller. [1] http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel.htm [2] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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