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path: root/drivers/of/overlay.c
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2017-10-19of: overlay: make pr_err() string uniqueFrank Rowand
The same error string occurs in drivers/of/resolver.c. Change the error here to more precisely describe this case, and avoid the possible confusion of looking in the wrong source location to understand the cause of an error. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-19of: overlay: pr_err from return NOTIFY_OK to overlay apply/removeFrank Rowand
A device tree overlay notifier can return NOTIFY_OK, NOTIFY_STOP, or an embedded errno. overlay_notify() incorrectly reports an error for NOTIFY_OK. Reported-by: atull@kernel.org Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: remove unneeded check for NULL kbasename()Frank Rowand
kbasename() will not return NULL if passed a valid string. If the parameter passed to kbasename() in this case is already NULL then the devicetree has been corrupted. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: remove a dependency on device node full_nameFrank Rowand
The "%pOF" printf format was recently added to print the full name of a device tree node, with the intent of changing the node full_name field to contain only the node name instead of the full path of the node. dup_and_fixup_symbol_prop() duplicates a property from the "/__symbols__" node of an overlay device tree. The value of each duplicated property must be fixed up to include the full path of a node in the live device tree. The current code uses the node's full_name for that purpose. Update the code to use the "%pOF" printf format to determine the node's full path. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: simplify applying symbols from an overlayFrank Rowand
The code to apply symbols from an overlay to the live device tree was implemented with the intent to be minimally intrusive on the existing code. After recent restructuring of the overlay apply code, it is easier to disintangle the code that applies the symbols, and to make the overlay changeset creation code more straight forward and understandable. Remove the extra complexity, and make the code more obvious. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: avoid race condition between applying multiple overlaysFrank Rowand
The process of applying an overlay consists of: - unflatten an overlay FDT (flattened device tree) into an EDT (expanded device tree) - fixup the phandle values in the overlay EDT to fit in a range above the phandle values in the live device tree - create the overlay changeset to reflect the contents of the overlay EDT - apply the overlay changeset, to modify the live device tree, potentially changing the maximum phandle value in the live device tree There is currently no protection against two overlay applies concurrently determining what range of phandle values are in use in the live device tree, and subsequently changing that range. Add a mutex to prevent multiple overlay applies from occurring simultaneously. Move of_resolve_phandles() into of_overlay_apply() so that it does not have to be duplicated by each caller of of_overlay_apply(). The test in of_resolve_phandles() that the overlay tree is detached is temporarily disabled so that old style overlay unittests do not fail. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: loosen overly strict phandle clash checkFrank Rowand
When an overlay contains a node that already exists in the live device tree, the overlay node is not allowed to change the phandle of the existing node. The existing check refused to allow an overlay node to set the node phandle even when the existing node did not have a phandle. Relax the check to allow an overlay node to set the phandle value if the existing node does not have a phandle. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: expand check of whether overlay changeset can be removedFrank Rowand
The test of whether it is safe to remove an overlay changeset looked at whether any node in the overlay changeset was in a subtree rooted at any more recently applied overlay changeset node. The test failed to determine whether any node in the overlay changeset was the root of a subtree that contained a more recently applied overlay changeset node. Add this additional check to the test. The test is still lacking any check for any phandle dependencies. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: detect cases where device tree may become corruptFrank Rowand
When an attempt to apply an overlay changeset fails, an effort is made to revert any partial application of the changeset. When an attempt to remove an overlay changeset fails, an effort is made to re-apply any partial reversion of the changeset. The existing code does not check for failure to recover a failed overlay changeset application or overlay changeset revert. Add the missing checks and flag the devicetree as corrupt if the state of the devicetree can not be determined. Improve and expand the returned errors to more fully reflect the result of the effort to undo the partial effects of a failed attempt to apply or remove an overlay changeset. If the device tree might be corrupt, do not allow further attempts to apply or remove an overlay changeset. When creating an overlay changeset from an overlay device tree, add some additional warnings if the state of the overlay device tree is not as expected. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: minor restructuringFrank Rowand
Continue improving the readability of overlay.c. The previous patches renamed identifiers. This patch is split out from the previous patches to make the previous patches easier to review. Changes are: - minor code restructuring - some initialization of an overlay changeset occurred outside of init_overlay_changeset(), move that into init_overlay_changeset() - consolidate freeing an overlay changeset into free_overlay_changeset() This patch is intended to not introduce any functional change. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: rename identifiers in dup_and_fixup_symbol_prop()Frank Rowand
More renaming of identifiers to better reflect what they do. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: rename identifiers to more reflect what they doFrank Rowand
This patch is aimed primarily at drivers/of/overlay.c, but those changes also have a small impact in a few other files. overlay.c is difficult to read and maintain. Improve readability: - Rename functions, types and variables to better reflect what they do and to be consistent with names in other places, such as the device tree overlay FDT (flattened device tree), and make the algorithms more clear - Use the same names consistently throughout the file - Update comments for name changes - Fix incorrect comments This patch is intended to not introduce any functional change. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay.c: Convert comparisons to zero or NULL to logical expressionsFrank Rowand
Use normal shorthand for comparing a variable to zero. For variable "XXX": convert (XXX == 0) to (!XXX) convert (XXX != 0) to (XXX) Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay.c: Remove comments that state the obvious, to reduce clutterFrank Rowand
Follows recommendations in Documentation/process/coding-style.rst, section 8, Commenting. Some in function comments are promoted to function header comments. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: fix memory leak related to duplicated propertyLixin Wang
Function of_changeset_add_property or of_changeset_update_property may fails. In this case the property just allocated is never deallocated. Signed-off-by: Lixin Wang <alan.1.wang@nokia-sbell.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-07-20of: overlay: add overlay symbols to live device treeFrank Rowand
Add overlay __symbols__ properties to live tree when an overlay is added to the live tree so that the symbols are available to subsequent overlays. Expected test result is new __symbols__ entries for labels from the overlay after this commit. Before this commit: Console error message near end of unittest: ### dt-test ### FAIL of_unittest_overlay_high_level():2296 Adding overlay 'overlay_bad_symbol' failed ### dt-test ### end of unittest - 190 passed, 1 failed The new unittest "fails" because the expected result of loading the new overlay is an error instead of success. $ # node hvac-medium-2 exists because the overlay loaded $ # since the duplicate symbol was not detected $ cd /proc/device-tree/testcase-data-2/substation@100/ $ ls compatible hvac-medium-2 motor-8 reg hvac-large-1 linux,phandle name status hvac-medium-1 motor-1 phandle $ cd /proc/device-tree/__symbols__/ $ ls electric_1 lights_1 name rides_1 spin_ctrl_2 hvac_1 lights_2 retail_1 spin_ctrl_1 After this commit: Previous console error message no longer occurs, but expected error occurs: OF: overlay: Failed to apply prop @/__symbols__/hvac_1 OF: overlay: apply failed '/__symbols__' ### dt-test ### end of unittest - 191 passed, 0 failed $ # node hvac-medium-2 does not exist because the overlay $ # properly failed to load due to the duplicate symbol $ cd /proc/device-tree/testcase-data-2/substation@100/ $ ls compatible hvac-medium-1 motor-1 name reg hvac-large-1 linux,phandle motor-8 phandle status $ cd /proc/device-tree/__symbols__/ $ ls electric_1 lights_1 retail_1 ride_200_right spin_ctrl_2 hvac_1 lights_2 ride_200 rides_1 hvac_2 name ride_200_left spin_ctrl_1 $ cat ride_200; echo /testcase-data-2/fairway-1/ride@200 $ cat ride_200_left ; echo /testcase-data-2/fairway-1/ride@200/track@10 $ cat ride_200_right ; echo /testcase-data-2/fairway-1/ride@200/track@20 Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-07-20of: overlay: correctly apply overlay node with unit-addressFrank Rowand
Correct existing node name detection when overlay node name has a unit-address. Expected test result is overlay will update the nodes and properties for /testcase-data-2/fairway-1/ride@100/ after this commit. Before this commit: Console error message near end of unittest: OF: Duplicate name in fairway-1, renamed to "ride@100#1" $ cd /proc/device-tree/testcase-data-2/fairway-1/ $ # extra node: ride@100#1 $ ls #address-cells linux,phandle phandle ride@200 #size-cells name ride@100 status compatible orientation ride@100#1 $ cd /proc/device-tree/testcase-data-2/fairway-1/ride@100/ $ ls track@30/incline-up ls: track@30/incline-up: No such file or directory $ ls track@40/incline-up ls: track@40/incline-up: No such file or directory After this commit: Console error message no longer occurs $ cd /proc/device-tree/testcase-data-2/fairway-1/ $ # no extra node: ride@100#1 $ ls #address-cells compatible name phandle ride@200 #size-cells linux,phandle orientation ride@100 status $ cd /proc/device-tree/testcase-data-2/fairway-1/ride@100/ $ ls track@30/incline-up track@30/incline-up $ ls track@40/incline-up track@40/incline-up Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-07-18of: Convert to using %pOF instead of full_nameRob Herring
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org>
2017-06-22of: detect invalid phandle in overlayFrank Rowand
Overlays are not allowed to modify phandle values of previously existing nodes because there is no information available to allow fixup up properties that use the previously existing phandle. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-01-09of: remove redundant memset in overlayXuYing
memset in of_build_overlay_info is redundant, the ovinfo has been zeroed in of_fill_overlay_info when error. Signed-off-by: YiPing Xu <xuyiping@hisilicon.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-01-04of: drop duplicate headersGeliang Tang
Drop duplicate headers string.h and of_platform.h. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Rob Herring <robh@kernel.org>
2016-11-10of/overlay: add of overlay notificationsAlan Tull
This patch add of overlay notifications. When DT overlays are being added, some drivers/subsystems need to see device tree overlays before the changes go into the live tree. This is distinct from reconfig notifiers that are post-apply or post-remove and which issue very granular notifications without providing access to the context of a whole overlay. The following 4 notificatons are issued: OF_OVERLAY_PRE_APPLY OF_OVERLAY_POST_APPLY OF_OVERLAY_PRE_REMOVE OF_OVERLAY_POST_REMOVE In the case of pre-apply notification, if the notifier returns error, the overlay will be rejected. This patch exports two functions for registering/unregistering notifications: of_overlay_notifier_register(struct notifier_block *nb) of_overlay_notifier_unregister(struct notifier_block *nb) The of_mutex is held during these notifications. The notification data includes pointers to the overlay target and the overlay: struct of_overlay_notify_data { struct device_node *overlay; struct device_node *target; }; Signed-off-by: Alan Tull <atull@opensource.altera.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Moritz Fischer <moritz.fischer@ettus.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-18of: use pr_fmt prefix for all console printingRob Herring
Clean-up all the DT printk functions to use common pr_fmt prefix. Some print statements such as kmalloc errors were redundant, so just drop those. Cc: Frank Rowand <frowand.list@gmail.com> Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Reviewed-by: Frank Rowand <frank.rowand@am.sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2016-01-13drivers/of: Export OF changeset functionsGavin Shan
The PowerNV PCI hotplug driver is going to use the OF changeset to manage the changed device sub-tree. This exports those OF changeset functions for that. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-10-22of/overlay: add missing of_node_putJulia Lawall
for_each_child_of_node performs an of_node_get on each iteration, so a break out of the loop requires an of_node_put. A simplified version of the semantic patch that fixes this problem is as follows (http://coccinelle.lip6.fr): // <smpl> @@ expression root,e; local idexpression child; @@ for_each_child_of_node(root, child) { ... when != of_node_put(child) when != e = child ( return child; | + of_node_put(child); ? return ...; ) ... } // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Rob Herring <robh@kernel.org>
2015-05-28of/overlay: Grammar s/an negative/a negative/Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rob Herring <robh@kernel.org>
2015-03-10of/overlay: Remove unused variableFabio Estevam
Commit 3e7f7626fd49a ("of/overlay: Do not generate duplicate nodes") removed the only use of the 'grandchild' variable, which leads to the following build warning: drivers/of/overlay.c: In function 'of_overlay_apply_single_device_node': drivers/of/overlay.c:89:31: warning: unused variable 'grandchild' [-Wunused-variable] struct device_node *tchild, *grandchild; ^ Remove this unused variable. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-03-02of/overlay: Directly include idr.hMark Brown
The overlay code uses IDRs but does not explicitly include the header providing the interface, instead relying on an implicit inclusion. Make the dependency explicit to avoid potential future build issues if the implicit inclusion goes away. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22of/overlay: Do not generate duplicate nodesPantelis Antoniou
During the course of the rewrites a bug sneaked in when dealing with children nodes of overlays, which ends up duplicating sub nodes. Simply remove the duplicate traversal of child nodes to fix. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Signed-off-by: Grant Likely <grant.likely@linaro.org>
2014-11-24of/overlay: Introduce DT overlay supportPantelis Antoniou
Overlays are a method to dynamically modify part of the kernel's device tree with dynamically loaded data. Add the core functionality to parse, apply and remove an overlay changeset. The core functionality takes care of managing the overlay data format and performing the add and remove. Drivers are expected to use the overlay functionality to support custom expansion busses commonly found on consumer development boards like the BeagleBone or Raspberry Pi. The overlay code uses CONFIG_OF_DYNAMIC changesets to perform the low level work of modifying the devicetree. Documentation about internal and APIs is provided in Documentation/devicetree/overlay-notes.txt v2: - Switch from __of_node_alloc() to __of_node_dup() - Documentation fixups - Remove 2-pass processing of properties - Remove separate ov_lock; just use the DT mutex. v1: - Drop delete capability using '-' prefix. The '-' prefixed names are valid properties and nodes and there is no need for it just yet. - Do not update special properties - name & phandle ones. - Change order of node attachment, so that the special property update works. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Signed-off-by: Grant Likely <grant.likely@linaro.org>