Commit Graph

41 Commits

Author SHA1 Message Date
Geert Uytterhoeven a514266ba6 of: overlay: Fix forgotten reference to of_overlay_apply()
While technically the ovcs_id is still returned by of_overlay_apply(),
this is an internal function.  All public callers of of_overlay_remove()
pass an ovcs_id returned by the public function of_overlay_fdt_apply().

Fixes: 39a751a4cb ("of: change overlay apply input data from unflattened to FDT")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
2018-03-17 18:18:38 -05:00
Frank Rowand b89dae1852 of: overlay: do not include path in full_name of added nodes
Struct device_node full_name no longer includes the full path name
when the devicetree is created from a flattened device tree (FDT).
The overlay node creation code was not modified to reflect this
change.  Fix the node full_name generated by overlay code to contain
only the basename.

Unittests call an overlay internal function to create new nodes.
Fix up these calls to provide basename only instead of the full
path.

Fixes: a7e4cfb0a7 ("of/fdt: only store the device node basename
in full_name")

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2018-03-05 15:38:34 -06:00
Frank Rowand e547c00316 of: improve reporting invalid overlay target path
Errors while developing the patch to create of_overlay_fdt_apply()
exposed inadequate error messages to debug problems when overlay
devicetree fragment nodes contain an invalid target path.  Improve
the messages in find_target_node() to remedy this.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
2018-03-04 00:29:40 -08:00
Frank Rowand 39a751a4cb of: change overlay apply input data from unflattened to FDT
Move duplicating and unflattening of an overlay flattened devicetree
(FDT) into the overlay application code.  To accomplish this,
of_overlay_apply() is replaced by of_overlay_fdt_apply().

The copy of the FDT (aka "duplicate FDT") now belongs to devicetree
code, which is thus responsible for freeing the duplicate FDT.  The
caller of of_overlay_fdt_apply() remains responsible for freeing the
original FDT.

The unflattened devicetree now belongs to devicetree code, which is
thus responsible for freeing the unflattened devicetree.

These ownership changes prevent early freeing of the duplicated FDT
or the unflattened devicetree, which could result in use after free
errors.

of_overlay_fdt_apply() is a private function for the anticipated
overlay loader.

Update unittest.c to use of_overlay_fdt_apply() instead of
of_overlay_apply().

Move overlay fragments from artificial locations in
drivers/of/unittest-data/tests-overlay.dtsi into one devicetree
source file per overlay.  This led to changes in
drivers/of/unitest-data/Makefile and drivers/of/unitest.c.

  - Add overlay directives to the overlay devicetree source files so
    that dtc will compile them as true overlays into one FDT data
    chunk per overlay.

  - Set CFLAGS for drivers/of/unittest-data/testcases.dts so that
    symbols will be generated for overlay resolution of overlays
    that are no longer artificially contained in testcases.dts

  - Unflatten and apply each unittest overlay FDT using
    of_overlay_fdt_apply().

  - Enable the of_resolve_phandles() check for whether the unflattened
    overlay is detached.  This check was previously disabled because the
    overlays from tests-overlay.dtsi were not unflattened into detached
    trees.

  - Other changes to unittest.c infrastructure to manage multiple test
    FDTs built into the kernel image (access by name instead of
    arbitrary number).

  - of_unittest_overlay_high_level(): previously unused code to add
    properties from the overlay_base devicetree to the live tree
    was triggered by the restructuring of tests-overlay.dtsi and thus
    testcases.dts.  This exposed two bugs: (1) the need to dup a
    property before adding it, and (2) property 'name' is
    auto-generated in the unflatten code and thus will be a duplicate
    in the __symbols__ node - do not treat this duplicate as an error.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
2018-03-04 00:29:24 -08:00
Rob Herring af6074fc9a of: Use SPDX license tag for DT files
Convert remaining DT files to use SPDX-License-Identifier tags.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2018-01-08 08:22:45 -06:00
Geert Uytterhoeven 589b754df3 of: overlay: Make node skipping in init_overlay_changeset() clearer
Make it more clear that nodes without "__overlay__" subnodes are
skipped, by reverting the logic and using continue.
This also reduces indentation level.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-08 09:32:18 -06:00
Geert Uytterhoeven 35e691eddc of: overlay: Fix out-of-bounds write in init_overlay_changeset()
If an overlay has no "__symbols__" node, but it has nodes without
"__overlay__" subnodes at the end (e.g. a "__fixups__" node), after
filling in all fragments for nodes with "__overlay__" subnodes,
"fragment = &fragments[cnt]" will point beyond the end of the allocated
array.

Hence writing to "fragment->overlay" will overwrite unallocated memory,
which may lead to a crash later.

Fix this by deferring both the assignment to "fragment" and the
offending write afterwards until we know for sure the node has an
"__overlay__" subnode, and thus a valid entry in "fragments[]".

Fixes: 61b4de4e0b ("of: overlay: minor restructuring")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-08 09:32:10 -06:00
Geert Uytterhoeven 5e4748175f of: overlay: Fix (un)locking in of_overlay_apply()
The special overlay mutex is taken first, hence it should be released
last in the error path.

of_resolve_phandles() must be called with of_mutex held.  Without it, a
node and new phandle could be added via of_attach_node(), making the max
phandle wrong.

free_overlay_changeset() must be called with of_mutex held, if any
non-trivial cleanup is to be done.

Hence move "mutex_lock(&of_mutex)" up, as suggested by Frank, and merge
the two tail statements of the success and error paths, now they became
identical.

Note that while the two mutexes are adjacent, we still need both:
__of_changeset_apply_notify(), which is called by __of_changeset_apply()
unlocks of_mutex, then does notifications then locks of_mutex.  So the
mutex get released in the middle of of_overlay_apply()

Fixes: f948d6d8b7 ("of: overlay: avoid race condition between applying multiple overlays")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-06 16:08:30 -06:00
Geert Uytterhoeven 1352f09b4c of: overlay: Fix memory leak in of_overlay_apply() error path
If of_resolve_phandles() fails, free_overlay_changeset() is called in
the error path.  However, that function returns early if the list hasn't
been initialized yet, before freeing the object.

Explicitly calling kfree() instead would solve that issue. However, that
complicates matter, by having to consider which of two different methods
to use to dispose of the same object.

Hence make free_overlay_changeset() consider initialization state of the
different parts of the object, making it always safe to call (once!) to
dispose of a (partially) initialized overlay_changeset:
  - Only destroy the changeset if the list was initialized,
  - Make init_overlay_changeset() store the ID in ovcs->id on success,
    to avoid calling idr_remove() with an error value or an already
    released ID.

Reported-by: Colin King <colin.king@canonical.com>
Fixes: f948d6d8b7 ("of: overlay: avoid race condition between applying multiple overlays")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-06 16:04:36 -06:00
Geert Uytterhoeven 6de67de326 of: overlay: Remove else after goto
If an "if" branch is terminated by a "goto", there's no need to have an
"else" statement and an indented block of code.

Remove the "else" statement to simplify the code flow for the casual
reviewer.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-06 14:56:33 -06:00
Geert Uytterhoeven e9d92e40ac of: Spelling s/changset/changeset/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-06 14:56:32 -06:00
Frank Rowand 4ee7c0d964 of: overlay: make pr_err() string unique
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>
2017-10-19 17:15:09 -05:00
Frank Rowand a1d19bd4cf of: overlay: pr_err from return NOTIFY_OK to overlay apply/remove
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>
2017-10-19 17:15:09 -05:00
Frank Rowand 34ca5d76f2 of: overlay: remove unneeded check for NULL kbasename()
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>
2017-10-17 20:47:56 -05:00
Frank Rowand e0a58f3e08 of: overlay: remove a dependency on device node full_name
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>
2017-10-17 20:47:37 -05:00
Frank Rowand 3912b7917a of: overlay: simplify applying symbols from an overlay
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>
2017-10-17 20:47:34 -05:00
Frank Rowand f948d6d8b7 of: overlay: avoid race condition between applying multiple overlays
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>
2017-10-17 20:47:27 -05:00
Frank Rowand 6d0f5470db of: overlay: loosen overly strict phandle clash check
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>
2017-10-17 20:47:22 -05:00
Frank Rowand 87f242c119 of: overlay: expand check of whether overlay changeset can be removed
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>
2017-10-17 20:47:17 -05:00
Frank Rowand 24789c5ce5 of: overlay: detect cases where device tree may become corrupt
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>
2017-10-17 20:47:14 -05:00
Frank Rowand 61b4de4e0b of: overlay: minor restructuring
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>
2017-10-17 20:46:59 -05:00
Frank Rowand 42b2e94fe8 of: overlay: rename identifiers in dup_and_fixup_symbol_prop()
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>
2017-10-17 20:46:55 -05:00
Frank Rowand 0290c4ca25 of: overlay: rename identifiers to more reflect what they do
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>
2017-10-17 20:46:17 -05:00
Frank Rowand bbed8794d5 of: overlay.c: Convert comparisons to zero or NULL to logical expressions
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>
2017-10-17 20:46:15 -05:00
Frank Rowand 646afc4ad7 of: overlay.c: Remove comments that state the obvious, to reduce clutter
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>
2017-10-17 20:46:13 -05:00
Lixin Wang ac0f3e30d8 of: overlay: fix memory leak related to duplicated property
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>
2017-10-17 08:55:54 -05:00
Frank Rowand d1651b03c2 of: overlay: add overlay symbols to live device tree
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>
2017-07-20 09:40:05 -05:00
Frank Rowand c1cd1e01fe of: overlay: correctly apply overlay node with unit-address
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>
2017-07-20 09:36:15 -05:00
Rob Herring 0d638a07d3 of: Convert to using %pOF instead of full_name
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>
2017-07-18 17:09:18 -05:00
Frank Rowand 7a12f45989 of: detect invalid phandle in overlay
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>
2017-06-22 11:19:09 -05:00
XuYing 261c73f3f6 of: remove redundant memset in overlay
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>
2017-01-09 14:21:23 -06:00
Geliang Tang 30965eeab5 of: drop duplicate headers
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>
2017-01-04 14:01:28 -06:00
Alan Tull 39a842e22c of/overlay: add of overlay notifications
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>
2016-11-10 17:03:35 +01:00
Rob Herring 606ad42aa3 of: use pr_fmt prefix for all console printing
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>
2016-07-18 16:57:42 -05:00
Gavin Shan 183223770a drivers/of: Export OF changeset functions
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>
2016-01-13 16:10:37 -06:00
Julia Lawall 001cf5048e of/overlay: add missing of_node_put
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>
2015-10-22 09:35:51 -05:00
Geert Uytterhoeven 94a8bf9740 of/overlay: Grammar s/an negative/a negative/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
2015-05-28 13:00:25 -05:00
Fabio Estevam d3a891652a of/overlay: Remove unused variable
Commit 3e7f7626fd ("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>
2015-03-10 10:34:33 -05:00
Mark Brown 0d1886df6f of/overlay: Directly include idr.h
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>
2015-03-02 08:08:40 -06:00
Pantelis Antoniou 3e7f7626fd of/overlay: Do not generate duplicate nodes
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>
2015-01-22 15:36:48 +00:00
Pantelis Antoniou 7518b5890d of/overlay: Introduce DT overlay support
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>
2014-11-24 22:25:10 +00:00