kernel/linux.git/drivers/acpi/property.c, branch v6.6.131

ACPI: property: Use ACPI functions in acpi_graph_get_next_endpoint() only

2026-01-11T14:21:42+00:00

[ Upstream commit 5d010473cdeaabf6a2d3a9e2aed2186c1b73c213 ] Calling fwnode_get_next_child_node() in ACPI implementation of the fwnode property API is somewhat problematic as the latter is used in the impelementation of the former. Instead of using fwnode_get_next_child_node() in acpi_graph_get_next_endpoint(), call acpi_get_next_subnode() directly instead. Signed-off-by: Sakari Ailus Reviewed-by: Laurent Pinchart Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20251001104320.1272752-3-sakari.ailus@linux.intel.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: property: Fix fwnode refcount leak in acpi_fwnode_graph_parse_endpoint()

2026-01-11T14:21:23+00:00

[ Upstream commit 593ee49222a0d751062fd9a5e4a963ade4ec028a ] acpi_fwnode_graph_parse_endpoint() calls fwnode_get_parent() to obtain the parent fwnode but returns without calling fwnode_handle_put() on it. This potentially leads to a fwnode refcount leak and prevents the parent node from being released properly. Call fwnode_handle_put() on the parent fwnode before returning to prevent the leak from occurring. Fixes: 3b27d00e7b6d ("device property: Move fwnode graph ops to firmware specific locations") Signed-off-by: Haotian Zhang Reviewed-by: Sakari Ailus [ rjw: Changelog edits ] Link: https://patch.msgid.link/20251111075000.1828-1-vulab@iscas.ac.cn Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: property: Return present device nodes only on fwnode interface

2025-11-24T09:29:49+00:00

[ Upstream commit d9f866b2bb3eec38b3734f1fed325ec7c55ccdfa ] fwnode_graph_get_next_subnode() may return fwnode backed by ACPI device nodes and there has been no check these devices are present in the system, unlike there has been on fwnode OF backend. In order to provide consistent behaviour towards callers, add a check for device presence by introducing a new function acpi_get_next_present_subnode(), used as the get_next_child_node() fwnode operation that also checks device node presence. Signed-off-by: Sakari Ailus Reviewed-by: Laurent Pinchart Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20251001102636.1272722-2-sakari.ailus@linux.intel.com [ rjw: Kerneldoc comment and changelog edits ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: property: Do not pass NULL handles to acpi_attach_data()

2025-10-19T14:31:00+00:00

[ Upstream commit baf60d5cb8bc6b85511c5df5f0ad7620bb66d23c ] In certain circumstances, the ACPI handle of a data-only node may be NULL, in which case it does not make sense to attempt to attach that node to an ACPI namespace object, so update the code to avoid attempts to do so. This prevents confusing and unuseful error messages from being printed. Also document the fact that the ACPI handle of a data-only node may be NULL and when that happens in a code comment. In addition, make acpi_add_nondev_subnodes() print a diagnostic message for each data-only node with an unknown ACPI namespace scope. Fixes: 1d52f10917a7 ("ACPI: property: Tie data nodes to acpi handles") Cc: 6.0+ # 6.0+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Sakari Ailus Tested-by: Sakari Ailus Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ACPI: property: Add code comments explaining what is going on

2025-10-19T14:31:00+00:00

[ Upstream commit 737c3a09dcf69ba2814f3674947ccaec1861c985 ] In some places in the ACPI device properties handling code, it is unclear why the code is what it is. Some assumptions are not documented and some pieces of code are based on knowledge that is not mentioned anywhere. Add code comments explaining these things. Signed-off-by: Rafael J. Wysocki Reviewed-by: Sakari Ailus Tested-by: Sakari Ailus Stable-dep-of: baf60d5cb8bc ("ACPI: property: Do not pass NULL handles to acpi_attach_data()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ACPI: property: Disregard references in data-only subnode lists

2025-10-19T14:31:00+00:00

[ Upstream commit d06118fe9b03426484980ed4c189a8c7b99fa631 ] Data-only subnode links following the ACPI data subnode GUID in a _DSD package are expected to point to named objects returning _DSD-equivalent packages. If a reference to such an object is used in the target field of any of those links, that object will be evaluated in place (as a named object) and its return data will be embedded in the outer _DSD package. For this reason, it is not expected to see a subnode link with the target field containing a local reference (that would mean pointing to a device or another object that cannot be evaluated in place and therefore cannot return a _DSD-equivalent package). Accordingly, simplify the code parsing data-only subnode links to simply print a message when it encounters a local reference in the target field of one of those links. Moreover, since acpi_nondev_subnode_data_ok() would only have one caller after the change above, fold it into that caller. Link: https://lore.kernel.org/linux-acpi/CAJZ5v0jVeSrDO6hrZhKgRZrH=FpGD4vNUjFD8hV9WwN9TLHjzQ@mail.gmail.com/ Signed-off-by: Rafael J. Wysocki Reviewed-by: Sakari Ailus Tested-by: Sakari Ailus Stable-dep-of: baf60d5cb8bc ("ACPI: property: Do not pass NULL handles to acpi_attach_data()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ACPI: property: Fix buffer properties extraction for subnodes

2025-10-19T14:30:45+00:00

commit d0759b10989c5c5aae3d455458c9fc4e8cc694f7 upstream. The ACPI handle passed to acpi_extract_properties() as the first argument represents the ACPI namespace scope in which to look for objects returning buffers associated with buffer properties. For _DSD objects located immediately under ACPI devices, this handle is the same as the handle of the device object holding the _DSD, but for data-only subnodes it is not so. First of all, data-only subnodes are represented by objects that cannot hold other objects in their scopes (like control methods). Therefore a data-only subnode handle cannot be used for completing relative pathname segments, so the current code in in acpi_nondev_subnode_extract() passing a data-only subnode handle to acpi_extract_properties() is invalid. Moreover, a data-only subnode of device A may be represented by an object located in the scope of device B (which kind of makes sense, for instance, if A is a B's child). In that case, the scope in question would be the one of device B. In other words, the scope mentioned above is the same as the scope used for subnode object lookup in acpi_nondev_subnode_extract(). Accordingly, rearrange that function to use the same scope for the extraction of properties and subnode object lookup. Fixes: 103e10c69c61 ("ACPI: property: Add support for parsing buffer property UUID") Cc: 6.0+ # 6.0+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Sakari Ailus Tested-by: Sakari Ailus Signed-off-by: Greg Kroah-Hartman

ACPI: property: Fix return value for nval == 0 in acpi_data_prop_read()

2025-02-17T08:40:13+00:00

[ Upstream commit ab930483eca9f3e816c35824b5868599af0c61d7 ] While analysing code for software and OF node for the corner case when caller asks to read zero items in the supposed to be an array of values I found that ACPI behaves differently to what OF does, i.e. 1. It returns -EINVAL when caller asks to read zero items from integer array, while OF returns 0, if no other errors happened. 2. It returns -EINVAL when caller asks to read zero items from string array, while OF returns -ENODATA, if no other errors happened. Amend ACPI implementation to follow what OF does. Fixes: b31384fa5de3 ("Driver core: Unified device properties interface for platform firmware") Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20250203194629.3731895-1-andriy.shevchenko@linux.intel.com [ rjw: Added empty line after a conditional ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

acpi: property: Let args be NULL in __acpi_node_get_property_reference

2024-01-25T23:35:51+00:00

[ Upstream commit bef52aa0f3de1b7d8c258c13b16e577361dabf3a ] fwnode_get_property_reference_args() may not be called with args argument NULL on ACPI, OF already supports this. Add the missing NULL checks and document this. The purpose is to be able to count the references. Fixes: 977d5ad39f3e ("ACPI: Convert ACPI reference args to generic fwnode reference args") Signed-off-by: Sakari Ailus Reviewed-by: Andy Shevchenko Reviewed-by: Heikki Krogerus Link: https://lore.kernel.org/r/20231109101010.1329587-2-sakari.ailus@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

ACPI: property: Allow _DSD buffer data only for byte accessors

2023-11-20T10:58:59+00:00

[ Upstream commit 046ece773cc77ef5d2a1431b188ac3d0840ed150 ] In accordance with ACPI specificication and _DSD data buffer representation the data there is an array of bytes. Hence, accessing it with something longer will create a sparse data which is against of how device property APIs work in general and also not defined in the ACPI specification (see [1]). Fix the code to emit an error if non-byte accessor is used to retrieve _DSD buffer data. Fixes: 369af6bf2c28 ("ACPI: property: Read buffer properties as integers") Link: https://uefi.org/specs/ACPI/6.5/19_ASL_Reference.html#buffer-declare-buffer-object # [1] Signed-off-by: Andy Shevchenko [ rjw: Add missing braces ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin