A value of '0' isn't a valid phandle, so searching for a node with that
phandle is pointless. It will result in nothing but false positives.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Simply swap of_alias and of_chosen initialization so
that of_alias ends up read first. This must be done
because it is accessed couple of lines below when
trying to initialize the of_stdout using the alias
based legacy method.

[Fixes a752ee56 - tty: Update hypervisor tty drivers to
use core stdout parsing code]
Signed-off-by: NLaurentiu Tudor <Laurentiu.Tudor@freescale.com>
[glikely: Don't move the 'if (!of_aliases)' test]
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

This patch is to the fix the recent runtime bug in kernel reported by
<fengguang.wu@intel.com>. The bug was exposed by commit b951f9dc,
"Enabling OF selftest to run without machine's devicetree" and is
exposed when CONFIG_OF_SELFTEST is enabled and CONFIG_SYSFS is
disabled.

Mail Subject: [OF test] BUG: unable to handle kernel NULL pointer
dereference at 00000038

Tested on x86 and arm architecture
Signed-off-by: NGaurav Minocha <gaurav.minocha.os@gmail.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

The comments above of_console_check() say that it will return TRUE if it
registers a preferred console, but add_preferred_console() uses a
0-equals-success convention, so this leaves of_console_check() with an
inconsistent policy for its return values.

Fortunately, nobody was actually checking the return value of
of_console_check(), so this isn't significant at the moment.

But let's match the comments, so we're doing what we say.

Fixes: 3482f2c5 ('of: Create of_console_check() for selecting a console specified in /chosen')
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Currently, devicetree reconfig notifiers get emitted before the change
is applied to the tree, but that behaviour is problematic if the
receiver wants the determine the new state of the tree. The current
users don't care, but the changeset code to follow will be making
multiple changes at once. Reorder notifiers to get emitted after the
change has been applied to the tree so that callbacks see the new tree
state.

At the same time, fixup the existing callbacks to expect the new order.
There are a few callbacks that compare the old and new values of a
changed property. Put both property pointers into the of_prop_reconfig
structure.

The current notifiers also allow the notifier callback to fail and
cancel the change to the tree, but that feature isn't actually used.
It really isn't valid to ignore a tree modification provided by firmware
anyway, so remove the ability to cancel a change to the tree.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>
Cc: Nathan Fontenot <nfont@austin.ibm.com>

PowerPC does an odd thing with dynamic nodes. It uses a notifier to
catch new node additions and set some of the values like name and type.
This makes no sense since that same code can be put directly into
of_attach_node(). Besides, all dynamic node users need this, not just
powerpc. Fix this problem by moving the logic out of arch/powerpc and
into drivers/of/dynamic.c.

It is also important to remove this notifier because we want to move the
firing of notifiers from before the tree is modified to after so that
the receiver gets a consistent view of the tree, but that is
incompatible with notifiers that modify the node.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>
Cc: Nathan Fontenot <nfont@austin.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>

All of the DT modification functions are split into two parts, the first
part manipulates the DT data structure, and the second part updates
sysfs, but the code isn't very consistent about how the second half is
called. They don't all enforce the same rules about when it is valid to
update sysfs, and there isn't any clarity on locking.

The transactional DT modification feature that is coming also needs
access to these functions so that it can perform all the structure
changes together, and then all the sysfs updates as a second stage
instead of doing each one at a time.

Fix up the second have by creating a separate __of_*_sysfs() function
for each of the helpers. The new functions have consistent naming (ie.
of_node_add() becomes __of_attach_node_sysfs()) and all of them now
defer if of_init hasn't been called yet.

Callers of the new functions must hold the of_mutex to ensure there are
no race conditions with of_init(). The mutex ensures that there will
only ever be one writer to the tree at any given time. There can still
be any number of readers and the raw_spin_lock is still used to make
sure access to the data structure is still consistent.

Finally, put the function prototypes into of_private.h so they are
accessible to the transaction code.
Signed-off-by: NPantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Changed suffix from _post to _sysfs to match existing code]
[grant.likely: Reorganized to eliminate trivial wrappers]
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

The DT overlay code will need to manipulate nodes and properties while
already holding the devicetree lock, or on nodes that are not yet
attached to the tree, but the current helper functions don't allow that.
Extract the core behaviour from the accessors and create the following
unlocked variants.

The unlocked variants require either the lock to already be held or for
the nodes to be detached from the tree. Changes to live nodes will not
get updated in sysfs, so the caller must arrange for housekeeping to
take place after dropping the lock.

The new functions are: __of_add_property(), __of_remove_property(),
__of_update_property(), __of_attach_node() and __of_detach_node().
Signed-off-by: NPantelis Antoniou <pantelis.antoniou@konsulko.com>
[Remove unnecessary diff hunks and rewrite commit text]
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Split the dynamic device tree code into a separate file to make it
really clear what features CONFIF_OF_DYNAMIC add to the kernel. Without
CONFIG_OF_DYNAMIC only properties can be changed, and notifiers do not
get sent. Enabling it turns on reference counting, notifiers and the
ability to add and remove nodes.

v2: Moved of_node_release() into dynamic.c
Signed-off-by: NGrant Likely <grant.likely@linaro.org>
Signed-off-by: NPantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Rob Herring <robh+dt@kernel.org>

We're overloading usage of of_aliases_mutex for sysfs changes,
so rename to something that is more generic.
Signed-off-by: NPantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

The evh_bytechan, hvc_opal and hvc_vio drivers all open code the parsing
of the stdout node in the device tree. This patch simplifies the driver
by removing the duplicated functionality.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

The devicetree has a binding for specifying the console device in the
/chosen node, but the kernel doesn't use it consistently. This change
adds an API for testing if a device node is a console, and adds a
preferred console entry if it is.

At the same time this patch removes the of_device_is_stdout_path() API
since it is unused.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>
Tested-by: NSascha Hauer <s.hauer@pengutronix.de>

of_find_node_by_path() is borked because of_allnodes is not guaranteed to
contain the root of the tree after using any of the dynamic update functions
because some other nodes ends up as of_allnodes.

Fixes: c22e650e of: Make of_find_node_by_path() handle /aliases
Reported-by: pantelis.antoniou@konsulko.com
Signed-off-by: NFrank Rowand <frank.rowand@sonymobile.com>
Signed-off-by: NRob Herring <robh@kernel.org>

This makes sure a format string cannot leak into the kobject name that
is constructed. (And splits the >80 character line.)
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NRob Herring <robh@kernel.org>

Add an early check for the node argument in __of_get_next_child and
of_get_next_available_child() to avoid dereferencing a NULL node pointer
a few lines after.

CC: Daniel Mack <zonque@gmail.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Make of_find_node_by_path() handle aliases as prefixes. To make this
work the name search is refactored to search by path component instead
of by full string. This should be a more efficient search, and it makes
it possible to start a search at a subnode of a tree.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NPantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Rework to not require allocating at runtime]
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

When iterating over nodes, sometimes it needs to be done when the DT
lock is already held. This patch makes an unlocked version of the
for_each_child_of_node() macro.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

The of_update_property() is intented to update a property in a node
and if the property does not exist, will add it.

The second search of the property is possibly won't be found, that
maybe removed by other thread just before the second search begain.

Using the __of_find_property() and __of_add_property() instead and
move them into lock operations.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
[grant.likely: conflict with another change in same function]
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Commit 75b57ecf ('of: Make device
nodes kobjects so they show up in sysfs') has turned Device Tree nodes
in kobjects and added a sysfs based representation for Device Tree
nodes. Since the sysfs logic is only available after the execution of
a core_initcall(), the patch took precautions in of_add_property() and
of_remove_property() to not do any sysfs related manipulation early in
the boot process.

However, it forgot to do the same for of_update_property(), which if
used early in the boot process (before core_initcalls have been
called), tries to call sysfs_remove_bin_file(), and crashes:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at /home/thomas/projets/linux-2.6/fs/kernfs/dir.c:1216 kernfs_remove_by_name_ns+0x80/0x88()
kernfs: can not remove '(null)', no directory
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.15.0-rc1-00127-g1d7e7b2-dirty #423
[<c0014910>] (unwind_backtrace) from [<c00110ec>] (show_stack+0x10/0x14)
[<c00110ec>] (show_stack) from [<c04c84b8>] (dump_stack+0x84/0x94)
[<c04c84b8>] (dump_stack) from [<c001d8c0>] (warn_slowpath_common+0x6c/0x88)
[<c001d8c0>] (warn_slowpath_common) from [<c001d90c>] (warn_slowpath_fmt+0x30/0x40)
[<c001d90c>] (warn_slowpath_fmt) from [<c0104468>] (kernfs_remove_by_name_ns+0x80/0x88)
[<c0104468>] (kernfs_remove_by_name_ns) from [<c0394d98>] (of_update_property+0xc0/0xf0)
[<c0394d98>] (of_update_property) from [<c0647248>] (mvebu_timer_and_clk_init+0xfc/0x194)
[<c0647248>] (mvebu_timer_and_clk_init) from [<c0640934>] (start_kernel+0x218/0x350)
[<c0640934>] (start_kernel) from [<00008070>] (0x8070)
---[ end trace 3406ff24bd97382e ]---
Unable to handle kernel NULL pointer dereference at virtual address 0000003c
pgd = c0004000
[0000003c] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W     3.15.0-rc1-00127-g1d7e7b2-dirty #423
task: c10ad4d8 ti: c10a2000 task.ti: c10a2000
PC is at kernfs_find_ns+0x8/0xf0
LR is at kernfs_find_and_get_ns+0x30/0x48
pc : [<c0103834>]    lr : [<c010394c>]    psr: 600001d3
sp : c10a3f34  ip : 00000073  fp : 00000000
r10: 00000000  r9 : cfffc240  r8 : cfdf2980
r7 : cf812c00  r6 : 00000000  r5 : 00000000  r4 : c10b45e0
r3 : c10ad4d8  r2 : 00000000  r1 : cf812c00  r0 : 00000000
Flags: nZCv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 0000404a  DAC: 00000015
Process swapper/0 (pid: 0, stack limit = 0xc10a2240)
Stack: (0xc10a3f34 to 0xc10a4000)
3f20:                                              c10b45e0 00000000 00000000
3f40: cf812c00 c010394c 00000063 cf812c00 00000001 cf812c00 cfdf29ac c03932cc
3f60: 00000063 cf812bc0 cfdf29ac cf812c00 ffffffff c03943f8 cfdf2980 c0104468
3f80: cfdf2a04 cfdf2980 cf812bc0 c06634b0 c10aa3c0 c0394da4 c10f74dc cfdf2980
3fa0: cf812bc0 c0647248 c10aa3c0 ffffffff c10de940 c10aa3c0 ffffffff c0640934
3fc0: ffffffff ffffffff c06404ec 00000000 00000000 c06634b0 00000000 10c53c7d
3fe0: c10aa434 c06634ac c10ae4c8 0000406a 414fc091 00008070 00000000 00000000
[<c0103834>] (kernfs_find_ns) from [<00000001>] (0x1)
Code: e5c89001 eaffffcf e92d40f0 e1a06002 (e1d023bc)
---[ end trace 3406ff24bd97382f ]---
Kernel panic - not syncing: Attempted to kill the idle task!
---[ end Kernel panic - not syncing: Attempted to kill the idle task!

To fix this problem, we simply skip the sysfs related calls in
of_update_property(), and rely on of_init() to fix up things when it
will be called, exactly as is done in of_add_property() and
of_remove_property().
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Fixes: 75b57ecf ("of: Make device nodes kobjects so they show up in sysfs")
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Signed-off-by: NGeert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: NRob Herring <robh@kernel.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

After searching for the old property, bail out with -ENODEV
if it was not found.

It is unnecessary to check if oldprop is NULL before removing
its binary file; the check was already done before.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NRob Herring <robh@kernel.org>

ePAPR 1.1 defines the "stdout-path" property for specifying the console
device, but Linux currently only handles the older "linux,stdout-path"
property. This patch adds parsing for the new property name.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

After the move to having device nodes be proper kobjects the lifecycle
of the node needs to be controlled better.

At first convert of_add_node() in the unflattened functions to
of_init_node() which initializes the kobject so that of_node_get/put
work correctly even before of_init is called.

Afterwards introduce of_node_is_initialized & of_node_is_attached that
query the underlying kobject about the state (attached means kobj
is visible in sysfs)

Using that make sure the lifecycle of the tree is correct at all
times.
Signed-off-by: NPantelis Antoniou <panto@antoniou-consulting.com>
[grant.likely: moved of_node_init() calls, fixed up locking, and
               dropped __of_populate() hunks]
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

The same data is now available in sysfs, so we can remove the code
that exports it in /proc and replace it with a symlink to the sysfs
version.

Tested on versatile qemu model and mpc5200 eval board. More testing
would be appreciated.

v5: Fixed up conflicts with mainline changes
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>

Device tree nodes are already treated as objects, and we already want to
expose them to userspace which is done using the /proc filesystem today.
Right now the kernel has to do a lot of work to keep the /proc view in
sync with the in-kernel representation. If device_nodes are switched to
be kobjects then the device tree code can be a whole lot simpler. It
also turns out that switching to using /sysfs from /proc results in
smaller code and data size, and the userspace ABI won't change if
/proc/device-tree symlinks to /sys/firmware/devicetree/base.

v7: Add missing sysfs_bin_attr_init()
v6: Add __of_add_property() early init fixes from Pantelis
v5: Rename firmware/ofw to firmware/devicetree
    Fix updating property values in sysfs
v4: Fixed build error on Powerpc
    Fixed handling of dynamic nodes on powerpc
v3: Fixed handling of duplicate attribute and child node names
v2: switch to using sysfs bin_attributes which solve the problem of
    reporting incorrect property size.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Tested-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>

If of_graph_parse_endpoint is given a parentless node instead of an
endpoint node, it is clearly a bug.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>

This patch adds a new struct of_endpoint which is then embedded in struct
v4l2_of_endpoint and contains the endpoint properties that are not V4L2
(or even media) specific: the port number, endpoint id, local device tree
node and remote endpoint phandle. of_graph_parse_endpoint parses those
properties and is used by v4l2_of_parse_endpoint, which just adds the
V4L2 MBUS information to the containing v4l2_of_endpoint structure.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>

A 'return endpoint;' at the end of the (!prev) case allows to
reduce the indentation level of the (prev) case.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>

If of_graph_get_next_endpoint is given a parentless node instead of an
endpoint node, it is clearly a bug.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>

This patch moves the parsing helpers used to parse connected graphs
in the device tree, like the video interface bindings documented in
Documentation/devicetree/bindings/media/video-interfaces.txt, from
drivers/media/v4l2-core/v4l2-of.c into drivers/of/base.c.

This allows to reuse the same parser code from outside the V4L2
framework, most importantly from display drivers.
The functions v4l2_of_get_next_endpoint, v4l2_of_get_remote_port,
and v4l2_of_get_remote_port_parent are moved. They are renamed to
of_graph_get_next_endpoint, of_graph_get_remote_port, and
of_graph_get_remote_port_parent, respectively.
Since there are not that many current users yet, switch all of
them to the new functions right away.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>

This reverts commit 02ed594e.

The change is completely broken. It attempt to get the previous item in
a linked list by grabbing the address of a stack variable. Outright
wrong.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

In the current implementation of __of_match_node(), it will compare
each given match entry against all the node's compatible strings
with of_device_is_compatible().

To achieve multiple compatible strings per node with ordering from
specific to generic, this requires given matches to be ordered from
specific to generic. For most of the drivers this is not true and
also an alphabetical ordering is more sane there.

Therefore, we define a following priority order for the match, and
then scan all the entries to find the best match.
  1. specific compatible && type && name
  2. specific compatible && type
  3. specific compatible && name
  4. specific compatible
  5. general compatible && type && name
  6. general compatible && type
  7. general compatible && name
  8. general compatible
  9. type && name
  10. type
  11. name

v5: Fix nested locking bug
v4: Short-circuit failure cases instead of mucking with score, and
    remove extra __of_device_is_compatible() wrapper stub.
    Move scoring logic directly into __of_device_is_compatible()
v3: Also need to bail out when there does have a compatible member in match
    entry, but it doesn't match with the device node's compatible.
v2: Fix the bug such as we get the same score for the following two match
    entries with the empty node 'name2 { };'
	struct of_device_id matches[] = {
		{.name = "name2", },
		{.name = "name2", .type = "type1", },
		{}
	};
Signed-off-by: NKevin Hao <haokexin@gmail.com>
[grant.likely: added v4 changes]
Signed-off-by: NGrant Likely <grant.likely@linaro.org>
Tested-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Tested-by: NStephen Chivers <schivers@csc.com>
Tested-by: NSachin Kamat <sachin.kamat@linaro.org>

This reverts commit 06b29e76.
As pointed out by Grant Likely, we should also take the type and name
into account when searching the best compatible match. That means the
match with compatible, type and name should be better than the match
just with the same compatible string. So revert this and we will
implement another method to find the best match entry.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

Currently, of_match_node compares each given match against all node's
compatible strings with of_device_is_compatible.

To achieve multiple compatible strings per node with ordering from
specific to generic, this requires given matches to be ordered from
specific to generic. For most of the drivers this is not true and also
an alphabetical ordering is more sane there.

Therefore, this patch introduces a function to match each of the node's
compatible strings against all given compatible matches without type and
name first, before checking the next compatible string. This implies
that node's compatibles are ordered from specific to generic while
given matches can be in any order. If we fail to find such a match
entry, then fall-back to the old method in order to keep compatibility.

Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Tested-by: NStephen Chivers <schivers@csc.com>
Signed-off-by: NRob Herring <robh@kernel.org>

This reverts commit 10535314.
Stephen Chivers reported this is broken as we will get a match
entry '.type = "serial"' instead of the '.compatible = "ns16550"'
in the following scenario:
	serial0: serial@4500 {
		compatible = "fsl,ns16550", "ns16550";
	}

	struct of_device_id of_platform_serial_table[] = {
		{ .compatible = "ns8250",   .data = (void *)PORT_8250, },
		{ .compatible = "ns16450",  .data = (void *)PORT_16450, },
		{ .compatible = "ns16550a", .data = (void *)PORT_16550A, },
		{ .compatible = "ns16550",  .data = (void *)PORT_16550, },
		{ .compatible = "ns16750",  .data = (void *)PORT_16750, },
		{ .compatible = "ns16850",  .data = (void *)PORT_16850, },
		...
		{ .type = "serial",         .data = (void *)PORT_UNKNOWN, },
		{ /* end of list */ },
	};

So just revert this patch, we will use another implementation to find
the best compatible match in a follow-on patch.
Reported-by: NStephen N Chivers <schivers@csc.com.au>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NRob Herring <robh@kernel.org>

The need to know the number of array elements in a property is
a common pattern. To prevent duplication of open-coded implementations
add a helper static function that also centralises strict sanity
checking and DTB format details, as well as a set of wrapper functions
for u8, u16, u32 and u64.
Suggested-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NHeiko Stuebner <heiko.stuebner@bqreaders.com>
Acked-by: NRob Herring <robh@kernel.org>
Acked-by: NGrant Likely <grant.likely@linaro.org>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

The of_update_property() is intented to update a property in a node
and if the property does not exist, will add it.

The second search of the property is possibly won't be found, that
maybe removed by other thread just before the second search begain.

Using the __of_find_property() and __of_add_property() instead and
move them into lock operations.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

There two places will use the same code for adding one new property to
the DT node. Adding __of_add_property() and prepare for fixing
of_update_property()'s bug.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

When attaching a node always clear the detach flag. Without this change
the sequence detach, attach fails.
Signed-off-by: NPantelis Antoniou <panto@antoniou-consulting.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

From IEEE 1275, there defined a standard 'status' property indicating the
operational status of one device. The 'status' property has four possible
values: 'okay/ok', 'disabled', 'fail' and 'fail-xxx'.

If it is absent, that means the status of the device is unknown or okay.

The __of_device_is_available checks the state of the 'status' property of
a device. If the property is absent or set to 'okay/ok', it returns 1.
Otherwise it returns 0.

While in __of_device_is_available:
 >	status = of_get_property(device, "status", &statlen);
 >	if (status == NULL)
 >		return 1;
The status value returned from 'of_get_property()' will be NULL in two cases:
Firstly: the 'device' value (device node) is NULL.
Secondly: the 'status' property is actaully not exist.

If the device node is NULL, the __of_device_is_available will return true,
that will mean the absent state of the 'status' property.

So this add the device node check before checking the 'status' property's
state, and if the device node is not exist, 0 will be returned.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>