kernel/linux.git/include/linux/fwnode.h, branch v5.10.258

device property: Allow error pointer to be passed to fwnode APIs

2026-04-18T08:31:17+00:00

[ Upstream commit 002752af7b89b74c64fe6bec8c5fde3d3a7810d8 ] Some of the fwnode APIs might return an error pointer instead of NULL or valid fwnode handle. The result of such API call may be considered optional and hence the test for it is usually done in a form of fwnode = fwnode_find_reference(...); if (IS_ERR(fwnode)) ...error handling... Nevertheless the resulting fwnode may have bumped the reference count and hence caller of the above API is obliged to call fwnode_handle_put(). Since fwnode may be not valid either as NULL or error pointer the check has to be performed there. This approach uglifies the code and adds a point of making a mistake, i.e. forgetting about error point case. To prevent this, allow an error pointer to be passed to the fwnode APIs. Fixes: 83b34afb6b79 ("device property: Introduce fwnode_find_reference()") Reported-by: Nuno Sá Tested-by: Nuno Sá Acked-by: Nuno Sá Reviewed-by: Sakari Ailus Reviewed-by: Heikki Krogerus Signed-off-by: Andy Shevchenko Tested-by: Michael Walle Signed-off-by: Rafael J. Wysocki Stable-dep-of: 2692c614f8f0 ("device property: Allow secondary lookup in fwnode_get_next_child_node()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

driver core: fw_devlink: Add support for batching fwnode parsing

2020-05-15T14:34:52+00:00

The amount of time spent parsing fwnodes of devices can become really high if the devices are added in an non-ideal order. Worst case can be O(N^2) when N devices are added. But this can be optimized to O(N) by adding all the devices and then parsing all their fwnodes in one batch. This commit adds fw_devlink_pause() and fw_devlink_resume() to allow doing this. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20200515053500.215929-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

driver core: Add fw_devlink kernel commandline option

2020-03-04T16:58:48+00:00

fwnode_operations.add_links allows creating device links from information provided by firmware. fwnode_operations.add_links is currently implemented only by OF/devicetree code and a specific case of efi. However, there's nothing preventing ACPI or other firmware types from implementing it. The OF implementation is currently controlled by a kernel commandline parameter called of_devlink. Since this feature is generic isn't limited to OF, add a generic fw_devlink kernel commandline parameter to control this feature across firmware types. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20200222014038.180923-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2019-11-27T19:06:20+00:00

Pull driver core updates from Greg KH: "Here is the "big" set of driver core patches for 5.5-rc1 There's a few minor cleanups and fixes in here, but the majority of the patches in here fall into two buckets: - debugfs api cleanups and fixes - driver core device link support for boot dependancy issues The debugfs api cleanups are working to slowly refactor the debugfs apis so that it is even harder to use incorrectly. That work has been happening for the past few kernel releases and will continue over time, it's a long-term project/goal The driver core device link support missed 5.4 by just a bit, so it's been sitting and baking for many months now. It's from Saravana Kannan to help resolve the problems that DT-based systems have at boot time with dependancy graphs and kernel modules. Turns out that no one has actually tried to build a generic arm64 kernel with loads of modules and have it "just work" for a variety of platforms (like a distro kernel). The big problem turned out to be a lack of dependency information between different areas of DT entries, and the work here resolves that problem and now allows devices to boot properly, and quicker than a monolith kernel. All of these patches have been in linux-next for a long time with no reported issues" * tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (68 commits) tracing: Remove unnecessary DEBUG_FS dependency of: property: Add device link support for interrupt-parent, dmas and -gpio(s) debugfs: Fix !DEBUG_FS debugfs_create_automount of: property: Add device link support for "iommu-map" of: property: Fix the semantics of of_is_ancestor_of() i2c: of: Populate fwnode in of_i2c_get_board_info() drivers: base: Fix Kconfig indentation firmware_loader: Fix labels with comma for builtin firmware driver core: Allow device link operations inside sync_state() driver core: platform: Declare ret variable only once cpu-topology: declare parse_acpi_topology in crypto: hisilicon: no need to check return value of debugfs_create functions driver core: platform: use the correct callback type for bus_find_device firmware_class: make firmware caching configurable driver core: Clarify documentation for fwnode_operations.add_links() mailbox: tegra: Fix superfluous IRQ error message net: caif: Fix debugfs on 64-bit platforms mac80211: Use debugfs_create_xul() helper media: c8sectpfe: no need to check return value of debugfs_create functions of: property: Add device link support for iommus, mboxes and io-channels ...

driver core: Clarify documentation for fwnode_operations.add_links()

2019-11-13T11:03:22+00:00

The wording was a bit ambiguous. So update it to make it clear. Signed-off-by: Saravana Kannan Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20191113023559.62295-2-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

driver core: Allow fwnode_operations.add_links to differentiate errors

2019-11-02T17:05:18+00:00

When add_links() still has suppliers that it needs to link to in the future, this patch allows it to differentiate between suppliers that are needed for probing vs suppliers that are needed for sync_state() correctness. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20191028220027.251605-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

driver: core: Improve documentation for fwnode_operations.add_links()

2019-10-17T12:57:03+00:00

The add_links() ops shouldn't return on the first failed device link add. It needs to continue trying to add device links to other suppliers that are available. The documentation didn't explain WHY this behavior is necessary. So, update the documentation with an example that explains why this is necessary. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20191011191521.179614-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

device property: Fix the description of struct fwnode_operations

2019-10-11T09:33:26+00:00

Adding description for the device_is_available member which was missing, and fixing the description of the member property_read_int_array. Signed-off-by: Heikki Krogerus Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki

device property: Add a function to obtain a node's prefix

2019-10-11T09:26:55+00:00

The prefix is used for printing purpose before a node, and it also works as a separator between two nodes. Signed-off-by: Sakari Ailus Acked-by: Rob Herring (for OF) Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki

device property: Add fwnode_get_name for returning the name of a node

2019-10-11T09:26:55+00:00

The fwnode framework did not have means to obtain the name of a node. Add that now, in form of the fwnode_get_name() function and a corresponding get_name fwnode op. OF and ACPI support is included. Signed-off-by: Sakari Ailus Acked-by: Rob Herring (for OF) Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki