Some of the exit paths were not correctly releasing the node. Fix it by
creating an 'err' label for collecting the error paths and releasing the
node.

Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

of_get_next_available_child() acquires devtree_lock, then calls
of_device_is_available() which calls of_get_property() which calls
of_find_property() which tries to re-acquire devtree_lock, thus causing
deadlock.

To avoid this, create a new __of_device_is_available() which calls
__of_get_property() instead, which calls __of_find_property(), which
does not take the lock,. Update of_get_next_available_child() to call
the new __of_device_is_available() since it already owns the lock.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

With the locking cleanup in place (from "OF: Fixup resursive
locking code paths"), we can now do the conversion from the
rw_lock to a raw spinlock as required for preempt-rt.

The previous cleanup and this conversion were originally
separate since they predated when mainline got raw spinlock (in
commit c2f21ce2 "locking: Implement new raw_spinlock").

So, at that point in time, the cleanup was considered plausible
for mainline, but not this conversion.  In any case, we've kept
them separate as it makes for easier review and better bisection.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
[PG: taken from preempt-rt, update subject & add a commit log]
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

In some situations, userspace may want to resolve a
device by function and logical number (ie, "serial0")
rather than by the base address or full device path. Being
able to resolve a device by alias frees userspace from the
burden of otherwise having to maintain a mapping between
device addresses and their logical assignments on each
platform when multiple instances of the same hardware block
are present in the system.

Although the uevent device attribute contains devicetree
compatible information and the full device path, the uevent
does not list the alises that may have been defined for the
device.
Signed-off-by: NStepan Moskovchenko <stepanm@codeaurora.org>
[grant.likely: Removed OF_ALIAS_N field; I don't think it's needed]
[grant.likely: Added #ifndef _LINUX_OF_PRIVATE_H wrapper]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

There is no real reason to use a rwlock for devtree_lock. It even
could be a mutex, but unfortunately it's locked from cpu hotplug
paths which can't schedule :(

So it needs to become a raw lock on rt as well.  The devtree_lock would
be the only user of a raw_rw_lock, so we are better off cleaning up the
recursive locking paths which allows us to convert devtree_lock to a
read_lock.

Here we do the standard thing of introducing __foo() as the "raw"
version of foo(), so that we can take better control of the locking.
The "raw" versions are not exported and are for internal use within
the file itself.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

The of_find_matching_node_and_match() function incorrectly sets the matched
entry to 'matches' when the compatible value of a node matches one of the
possible values. This results in incorrectly selecting the the first entry in
the 'matches' list as the matched entry. Fix this by noting down the result of
the call to of_match_node() and setting that as the matched entry.
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Commit 50c8af4c, "of: introduce for_each_matching_node_and_match()"
renamed of_find_matching_node() to of_find_matching_node_and_match() and
created a new static inline of_find_matching_node() wrapper around the
new name. However, the change neglected to change the EXPORT_SYMBOL()
reference causing build errors for modules.

This patch fixes the EXPORT_SYMBOL() statement. Discovered on a PowerPC
Efika build with the mpc52xx_uart driver being built as a module.
Reported-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The "struct device_node *" argument of of_parse_phandle_with_args() can
be const. Making this change makes it explicit that the function will
not modify a node.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
[grant.likely: Resolved conflict with previous patch modifying of_parse_phandle()]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

ERROR: "allnodes" [drivers/w1/masters/w1-gpio.ko] undefined!
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
[grant.likely: allnodes is too generic; rename to of_allnodes]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Ville Syrjala <syrjala@sci.fi>

The existing function does not change the passed device_node pointer. It is
only handed to of_get_property which itself takes a const struct device_node.

of_parse_phandle() can therefore take a const pointer as well.
Signed-off-by: NSteffen Trumtrar <s.trumtrar@pengutronix.de>
[grant.likely: drop extraneous whitespace change]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The of reconfiguration notification chains should be exported for use
by modules.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The following pattern of code is tempting:

    for_each_matching_node(np, table) {
        match = of_match_node(table, np);

However, this results in iterating over table twice; the second time
inside of_match_node(). The implementation of for_each_matching_node()
already found the match, so this is redundant. Invent new function
of_find_matching_node_and_match() and macro
for_each_matching_node_and_match() to remove the double iteration,
thus transforming the above code to:

    for_each_matching_node_and_match(np, table, &match)
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

This adds following helper routines:
- of_property_read_u8_array()
- of_property_read_u16_array()
- of_property_read_u8()
- of_property_read_u16()

This expects arrays from DT to be passed as:
- u8 array:
	property = /bits/ 8 <0x50 0x60 0x70>;
- u16 array:
	property = /bits/ 16 <0x5000 0x6000 0x7000>;
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Rename the prom_*_property routines of the generic OF code to of_*_property.
This brings them in line with the naming used by the rest of the OF code.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: NGeoff Levand <geoff@infradead.org>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This patch moves the notification chain for updates to the device tree
from the powerpc/pseries code to the base OF code. This makes this
functionality available to all architectures.

Additionally the notification chain is updated to allow notifications
for property add/remove/update. To make this work a pointer to a new
struct (of_prop_reconfig) is passed to the routines in the notification chain.
The of_prop_reconfig property contains a pointer to the node containing the
property and a pointer to the property itself. In the case of property
updates, the property pointer refers to the new property.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

When adding or removing a device tree node we should also update
the device tree in /proc/device-tree. This action is already done in the
generic OF code for adding/removing properties of a node. This patch adds
this functionality for nodes.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This patch introduces of_get_child_by_name function to get a child node
by its name in a given parent node.

Without this patch each driver code has to iterate the parent and do
a string compare, However having of_get_child_by_name libary function would
avoid code duplication, errors and is more convenient.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Macro for_each_child_of_node() makes it easy to iterate over all of the
children for a given device tree node, including those nodes that are
marked as unavailable (i.e. status = "disabled").

Introduce for_each_available_child_of_node(), which is like
for_each_child_of_node(), but it automatically skips unavailable nodes.
This also requires the introduction of helper function
of_get_next_available_child(), which returns the next available child
node.
Signed-off-by: NTimur Tabi <timur@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

prom_update_property() currently fails if the property doesn't
actually exist yet which isn't what we want. Change to add-or-update
instead of update-only, then we can remove a lot duplicated lines.
Suggested-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NDong Aisheng <dong.aisheng@linaro.org>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This reverts commit 107a84e6.

Meelis Roos reports a regression since 3.5-rc5 that stops Sun Fire V100
and Sun Netra X1 sparc64 machines from booting, hanging after enabling
serial console.  He bisected it to commit 107a84e6.

Rob Herring explains:
 "The problem is match combinations of compatible plus name and/or type
  fail to match correctly.  I have a fix for this, but given how late it
  is for 3.5 I think it is best to revert this for now.  There could be
  other cases that rely on the current although wrong behavior.  I will
  post an updated version for 3.6."
Bisected-and-reported-by: NMeelis Roos <mroos@linux.ee>
Requested-by: NRob Herring <rob.herring@calxeda.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The pattern (np ? np->full_name : "<none>") is rather common in the
kernel, but can also make for quite long lines.  This patch adds a new
inline function, of_node_full_name() so that the test for a valid node
pointer doesn't need to be open coded at all call sites.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Make of_parse_phandle_with_args return -ENOENT instead of -EINVAL when
no matching property is found, which allows to discriminate between
absence of property and parsing error.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Fixes the following sparse warnings:
drivers/of/base.c:176:41: warning: Using plain integer as NULL pointer
drivers/of/base.c:178:37: warning: Using plain integer as NULL pointer
drivers/of/base.c:500:49: warning: Using plain integer as NULL pointer
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

The pattern (np ? np->full_name : "<none>") is rather common in the
kernel, but can also make for quite long lines.  This patch adds a new
inline function, of_node_full_name() so that the test for a valid node
pointer doesn't need to be open coded at all call sites.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

When matching devices against an OF device ID table, the first string of
the compatible property that is listed in the table should match,
regardless of its position in the table.

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

This patch adds macros of_property_for_each_u32() and
of_property_for_each_string(), which iterate over an array of values
within a device-tree property. Usage is for example:

struct property *prop;
const __be32 *p;
u32 u;
of_property_for_each_u32(np, "propname", prop, p, u)
	printk("U32 value: %x\n", u);

struct property *prop;
const char *s;
of_property_for_each_string(np, "propname", prop, s)
	printk("String value: %s\n", s);

Based on work by Rob Herring <robherring2@gmail.com>

Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Only two architectures use the OF node reference counting and reclaim bits.
There is no need to compile it for the rest of the PowerPC platforms or for
any of the other architectures.  This patch makes iseries and pseries
select CONFIG_OF_DYNAMIC, and makes it default to off for everything else.

It is still safe to turn on CONFIG_OF_DYNAMIC on all architectures, it just
isn't necessary.

v2: Also select OF_DYNAMIC for PPC_CHROMA and MPC885ADS as reported by Michael
    Meuling
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jimi Xenidis <jimix@pobox.com> (for PPC_CHROMA bug fix)
Cc: Rob Herring <rob.herring@calxeda.com>

Add a helper function for finding the index of a string in a string
list property.  This helper is useful for bindings that use a separate
*-name property for attaching names to tuples in another property such
as 'reg' or 'gpios'.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Make this macro easier to use(do not need to pass properties, a node is
enough), also change to a more sensible name as for_each_child_of_node.
Signed-off-by: NDong Aisheng <dong.aisheng@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

The current implementation just ignore any NULL string inserted in a
multiple strings property.
In some cases we can have a property with a fix number of strings but
not necessarily used, like for example in a list of valid pinmux modes.

 prop = "uart_rx", "uart_tx", "", "", "safe_mode";

Do no skip NULL string and take them into account in
of_property_read_string_index and of_property_count_strings.
Reported-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBenoit Cousson <b-cousson@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

of_parse_phandle_with_args() needs to return quite a bit of data.  Rather
than making each datum a separate **out_ argument, this patch creates
struct of_phandle_args to contain all the returned data and reworks the
user of the function.  This patch also enables of_parse_phandle_with_args()
to return the device node pointer for the phandle node.

This patch also ends up being fairly major surgery to
of_parse_handle_with_args().  The existing structure didn't work well
when extending to use of_phandle_args, and I discovered bugs during testing.
I also took the opportunity to rename the function to be like the
existing of_parse_phandle().

v2: - moved declaration of of_phandle_args to fix compile on non-DT builds
    - fixed incorrect index in example usage
    - fixed incorrect return code handling for empty entries
Reviewed-by: NShawn Guo <shawn.guo@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Add a helper similar to of_property_read_u32() that handles 64-bit
integers.

v2/v3: constify device node and property name parameters.

Cc: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NJamie Iles <jamie@jamieiles.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Add of_property_read_string_index and of_property_count_strings
to retrieve one string inside a property that will contains
severals strings.
Signed-off-by: NBenoit Cousson <b-cousson@ti.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NKevin Hilman <khilman@ti.com>

The patch adds function of_alias_scan to populate a global lookup
table with the properties of 'aliases' node and function
of_alias_get_id for drivers to find alias id from the lookup table.

v3: Split out automatic addition of aliases on id lookup so that it can be
    debated separately from the core functionality.
v2: - Add of_chosen/of_aliases populating and of_alias_scan() invocation
    for OF_PROMTREE.
    - Add locking
    - rework parse loop
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

This reverts commit 750f463a.

of_alias_* still needs work to be generalized for 'promtree' dt
platforms, and to no implicitly create entries for available ids.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The patch adds function of_alias_scan to populate a global lookup
table with the properties of 'aliases' node and function
of_alias_get_id for drivers to find alias id from the lookup table.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
[grant.likely: add locking and rework parse loop]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The helper functions for reading u32 integers, u32 arrays and strings
should have the property name as a const pointer.

Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NJamie Iles <jamie@jamieiles.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Rework of_property_read_u32 to read an array of values. Then
of_property_read_u32 becomes an inline with array size of 1.

Also make struct device_node ptr const.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The existing dt codes usually call of_get_property to get a string
property and save it as a 'const char *'.  The patch adds'const' for
of_property_read_string parameter **out_string to make the converting
of existing code a little easier.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Add helper functions to retrieve unsigned integer and string property
values from properties of a device node. These helper functions can be
used to lookup a property in a device node, perform error checking and
read the property value.

[grant.likely@secretlab.ca: Proposal and initial implementation]
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
[grant.likely: some word smithing and be more defensive validating the string]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>