Add support for creating device links out of the following DT bindings:
- interrupts-extended
- nvmem-cells
- phys
- wakeup-parent
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200724234415.1651639-1-saravanak@google.comSigned-off-by: NRob Herring <robh@kernel.org>

Consider this example where -> means LHS device is a consumer of RHS
device and indentation represents "child of" of the previous device.

Device A -> Device C

Device B -> Device A
	Device C

Without this commit:
1. Device A is added.
2. Device A is added to waiting for supplier list (Device C)
3. Device B is added
4. Device B is linked as a consumer to Device A
5. Device A doesn't probe because it's waiting for Device C to be added.
6. Device B doesn't probe because Device A hasn't probed.
7. Device C will never be added because it's parent hasn't probed.

So, Device A, B and C will be in a probe/add deadlock.

This commit detects this scenario and stops trying to create a device
link between Device A and Device C since doing so would create the
following cycle:
Device A -> Devic C -(parent)-> Device B -> Device A.

With this commit:
1. Device A is added.
3. Device B is added
4. Device B is linked as a consumer to Device A
5. Device A probes.
6. Device B probes because Device A has probed.
7. Device C is added and probed.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200610011934.49795-3-saravanak@google.comSigned-off-by: NRob Herring <robh@kernel.org>

When creating a consumer/supplier relationship between two devices,
make sure the supplier node is actually active. Otherwise this will
create a link relationship that will never be fulfilled. This, in the
worst case scenario, will hang the system during boot.

Note that, in practice, the fact that a device-tree represented
consumer/supplier relationship isn't fulfilled will not prevent devices
from successfully probing.

Fixes: a3e1d1a7 ("of: property: Add functional dependency link from DT bindings")
Signed-off-by: NNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: NSaravana Kannan <saravanak@google.com>
Signed-off-by: NRob Herring <robh@kernel.org>

Upon adding a new device from a DT node, we scan its properties and its
children's properties in order to create a consumer/supplier
relationship between the device and the property provider.

That said, it's possible for some of the node's children to be disabled,
which will create links that'll never be fulfilled.

To get around this, use the for_each_available_child_of_node() function
instead of for_each_available_node() when iterating over the node's
children.

Fixes: d4387cd1 ("of: property: Create device links for all child-supplier depencencies")
Signed-off-by: NNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: NSaravana Kannan <saravanak@google.com>
Signed-off-by: NRob Herring <robh@kernel.org>

When of_link_to_phandle() was implemented initially, there was no way to
tell if device_link_add() was failing because the supplier device hasn't
been parsed yet, hasn't been added yet, the links were creating a cycle,
etc. Some of these were transient errors that'd go away at a later
point.

However, with the current set of improved checks, if device_link_add()
fails, it'll only be for permanent errors like cycles or out-of-memory
errors.

Also, with the addition of DL_FLAG_SYNC_STATE_ONLY flag [1] to device
links, all the valid dependency cycles due to "proxy" device links
(needed for correctness of sync_state() device callback) will never fail
device_link_add() due to cycles.

So, continuing to retry failing device links (by returning -EAGAIN) is
no longer useful. At worst, it prevents platforms from setting
fw_devlink=on (or better) because it prevents proper boot up. So, let's
not do that anymore.

[1] - https://lore.kernel.org/lkml/20191028220027.251605-1-saravanak@google.com/
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Tested-by: NNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: NRob Herring <robh@kernel.org>

Add support for creating device links out of more DT properties.

Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Signed-off-by: NRob Herring <robh@kernel.org>

With the addition of fw_devlink kernel commandline option, of_devlink is
redundant and not useful anymore. So, delete it.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-6-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The fw_devlink_get_flags() provides the right flags to use when creating
mandatory device links derived from information provided by the
firmware. So, use that.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-5-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for creating device links out of more DT properties.

To: lkml <linux-kernel@vger.kernel.org>
To: John Stultz <john.stultz@linaro.org>
To: Rob Herring <robh@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Tested-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NRob Herring <robh@kernel.org>

Add support for creating device links out of more DT properties.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vinod Koul <vkoul@kernel.org>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20191120071302.227777-1-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 8e12257d ("of: property: Add device link support for iommus,
mboxes and io-channels") added device link support for IOMMU linkages
described using the "iommus" property. For PCI devices, this property
is not present and instead the "iommu-map" property is used on the host
bridge node to map the endpoint RequesterIDs to their corresponding
IOMMU instance.

Add support for "iommu-map" to the device link supplier bindings so that
probing of PCI devices can be deferred until after the IOMMU is
available.

Cc: Rob Herring <robh@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>
Acked-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191120190028.4722-1-will@kernel.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The of_is_ancestor_of() function was renamed from of_link_is_valid()
based on review feedback. The rename meant the semantics of the function
had to be inverted, but this was missed in the earlier patch.

So, fix the semantics of of_is_ancestor_of() and invert the conditional
expressions where it is used.

Fixes: a3e1d1a7 ("of: property: Add functional dependency link from DT bindings")
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191120080230.16007-1-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Property fetching functions which return number of successfully fetched
properties should not state that out-values are only modified if 0 is
returned. Fix this. Also, "pointer to return value" is slightly suboptimal
phrase as "return value" commonly refers to value function returns (not via
arguments). Rather use "pointer to found values".
Signed-off-by: NMatti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: NFrank Rowand <frowand.list@gmail.com>
Signed-off-by: NRob Herring <robh@kernel.org>

Add support for creating device links out of more DT properties.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20191105065000.50407-4-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a DEFINE_SIMPLE_PROP macro to make it easy to add support for simple
properties with fixed names that just list phandles and phandle args.

Add a DEFINE_SUFFIX_PROP macro to make it easy to add support for
properties with fixes suffix that just list phandles and phandle args.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20191105065000.50407-3-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Adding a debug log instead of silently ignoring a phandle for an early
device. Also, return the right error code instead of 0 even though the
actual execution flow won't change.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20191105065000.50407-2-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some devices need to be initialized really early and can't wait for
driver core or drivers to be functional.  These devices are typically
initialized without creating a struct device for their device nodes.

If a supplier ends up being one of these devices, skip trying to add
device links to them.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-6-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When creating device links to proxy the sync_state() needs of child
dependencies, create SYNC_STATE_ONLY device links so that children
dependencies don't block probing of the parent.

Also, differentiate between missing suppliers of parent device vs
missing suppliers of child devices so that driver core doesn't block
parent device probing when only child supplier dependencies are missing.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-5-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Better variable and function names. Remove "," after the sentinel in an
array initialization list.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Acked-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20191011191521.179614-2-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The prefix is used for printing purpose before a node, and it also works
as a separator between two nodes.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Rob Herring <robh@kernel.org> (for OF)
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The fwnode framework did not have means to obtain the name of a node. Add
that now, in form of the fwnode_get_name() function and a corresponding
get_name fwnode op. OF and ACPI support is included.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Rob Herring <robh@kernel.org> (for OF)
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

A parent device can have child devices that it adds when it probes. But
this probing of the parent device can happen way after kernel init is done
-- for example, when the parent device's driver is loaded as a module.

In such cases, if the child devices depend on a supplier in the system, we
need to make sure the supplier gets the sync_state() callback only after
these child devices are added and probed.

To achieve this, when creating device links for a device by looking at its
DT node, don't just look at DT references at the top node level. Look at DT
references in all the descendant nodes too and create device links from the
ancestor device to all these supplier devices.

This way, when the parent device probes and adds child devices, the child
devices can then create their own device links to the suppliers and further
delay the supplier's sync_state() callback to after the child devices are
probed.

Example:
In this illustration, -> denotes DT references and indentation
represents child status.

Device node A
	Device node B -> D
	Device node C -> B, D

Device node D

Assume all these devices have their drivers loaded as modules.

Without this patch, this is the sequence of events:
1. D is added.
2. A is added.
3. Device D probes.
4. Device D gets its sync_state() callback.
5. Device B and C might malfunction because their resources got
   altered/turned off before they can make active requests for them.

With this patch, this is the sequence of events:
1. D is added.
2. A is added and creates device links to D.
3. Device link from A to B is not added because A is a parent of B.
4. Device D probes.
5. Device D does not get it's sync_state() callback because consumer A
   hasn't probed yet.
5. Device A probes.
5. a. Devices B and C are added.
5. b. Device links from B and C to D are added.
5. c. Device A's probe completes.
6. Device D does not get it's sync_state() callback because consumer A
   has probed but consumers B and C haven't probed yet.
7. Device B and C probe.
8. Device D gets it's sync_state() callback because all its consumers
   have probed.
9. None of the devices malfunction.
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-7-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add device links after the devices are created (but before they are
probed) by looking at common DT bindings like clocks and
interconnects.

Automatically adding device links for functional dependencies at the
framework level provides the following benefits:

- Optimizes device probe order and avoids the useless work of
  attempting probes of devices that will not probe successfully
  (because their suppliers aren't present or haven't probed yet).

  For example, in a commonly available mobile SoC, registering just
  one consumer device's driver at an initcall level earlier than the
  supplier device's driver causes 11 failed probe attempts before the
  consumer device probes successfully. This was with a kernel with all
  the drivers statically compiled in. This problem gets a lot worse if
  all the drivers are loaded as modules without direct symbol
  dependencies.

- Supplier devices like clock providers, interconnect providers, etc
  need to keep the resources they provide active and at a particular
  state(s) during boot up even if their current set of consumers don't
  request the resource to be active. This is because the rest of the
  consumers might not have probed yet and turning off the resource
  before all the consumers have probed could lead to a hang or
  undesired user experience.

  Some frameworks (Eg: regulator) handle this today by turning off
  "unused" resources at late_initcall_sync and hoping all the devices
  have probed by then. This is not a valid assumption for systems with
  loadable modules. Other frameworks (Eg: clock) just don't handle
  this due to the lack of a clear signal for when they can turn off
  resources. This leads to downstream hacks to handle cases like this
  that can easily be solved in the upstream kernel.

  By linking devices before they are probed, we give suppliers a clear
  count of the number of dependent consumers. Once all of the
  consumers are active, the suppliers can turn off the unused
  resources without making assumptions about the number of consumers.

By default we just add device-links to track "driver presence" (probe
succeeded) of the supplier device. If any other functionality provided
by device-links are needed, it is left to the consumer/supplier
devices to change the link when they probe.

kbuild test robot reported clang error about missing const
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-4-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The node returned by of_graph_get_endpoint_by_regs has a reference taken,
and we need to put that reference back when done with the node.

However, the documentation for that node doesn't mention it, so let's make
sure it does.
Signed-off-by: NMaxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: NRob Herring <robh@kernel.org>

Add an of_node_put when the result of of_graph_get_remote_port_parent is
not available.

The semantic match that finds this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@r exists@
local idexpression e;
expression x;
@@
e = of_graph_get_remote_port_parent(...);
... when != x = e
    when != true e == NULL
    when != of_node_put(e)
    when != of_fwnode_handle(e)
(
return e;
|
*return ...;
)
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Cc: stable@vger.kernel.org
Signed-off-by: NRob Herring <robh@kernel.org>

Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: NRob Herring <robh@kernel.org>

Constify device_get_match_data() as OF and ACPI variants return
constant value.
Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NFrank Rowand <frank.rowand@sony.com>
Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: NRob Herring <robh@kernel.org>

Now that we have a get_match_data() callback as part of the firmware node,
implement the OF specific piece for it.
Signed-off-by: NSinan Kaya <okaya@codeaurora.org>
Reviewed-by: NRob Herring <robh@kernel.org>
Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The fwnode_handle_get() function is used to obtain a reference to an
fwnode. A common usage pattern for the OF equivalent of the function is:

	mynode = of_node_get(node);

Similarly make fwnode_handle_get() return the fwnode to which the
reference was obtained.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Using CONFIG_OF_DYNAMIC=y uncovered an imbalance in the usecount of the
node being passed to of_fwnode_graph_get_port_parent(). Preserve the
usecount by using of_get_parent() instead of of_get_next_parent() which
don't decrement the usecount of the node passed to it.

Fixes: 3b27d00e ("device property: Move fwnode graph ops to firmware specific locations")
Signed-off-by: NNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NRob Herring <robh@kernel.org>

Now, we can use of_graph_get_remote_endpoint(). Let's use it.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NRob Herring <robh@kernel.org>

Fix inconsistent use of of_graph_get_port_parent() where
asoc_simple_card_parse_graph_dai() does of_node_get() before
calling it while other callers do not. We can fix this by
not trashing the node passed to of_graph_get_port_parent().

Let's also make sure the callers have correct refcounts and remove
related incorrect of_node_put() calls for of_for_each_phandle
as that's done by of_phandle_iterator_next() except when
we break out of the loop early.

Let's fix both issues with a single patch to avoid kobject
refcounts getting messed up more if two patches are merged
separately.

Otherwise strange issues can happen caused by memory corruption
caused by too many kobject_del() calls such as:

BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:747
...
(___might_sleep)
(__mutex_lock)
(mutex_lock_nested)
(kernfs_remove)
(kobject_del)
(kobject_put)
(of_get_next_parent)
(of_graph_get_port_parent)
(asoc_simple_card_parse_graph_dai [snd_soc_simple_card_utils])
(asoc_graph_card_probe [snd_soc_audio_graph_card])

Fixes: 0ef472a9 ("of_graph: add of_graph_get_port_parent()")
Fixes: 2692c1c6 ("ASoC: add audio-graph-card support")
Fixes: 1689333f ("ASoC: simple-card-utils: add asoc_simple_card_parse_graph_dai()")
Signed-off-by: NTony Lindgren <tony@atomide.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Tested-by: NAntonio Borneo <borneo.antonio@gmail.com>
Tested-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The new fwnode_property_get_reference_args() interface amends the fwnode
property API with the functionality of both of_parse_phandle_with_args()
and __acpi_node_get_property_reference().

The semantics is slightly different: the cells property is ignored on ACPI
as the number of arguments can be explicitly obtained from the firmware
interface.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Make fwnode arguments to the fwnode property API const.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Instead of relying on the struct fwnode_handle type field, define
fwnode_operations structs for all separate types of fwnodes. To find out
the type, compare to the ops field to relevant ops structs.

This change has two benefits:

1. it avoids adding the type field to each and every instance of struct
fwnode_handle, thus saving memory and

2. makes the ops field the single factor that defines both the types of
the fwnode as well as defines the implementation of its operations,
decreasing the possibility of bugs when developing code dealing with
fwnode internals.
Suggested-by: NRob Herring <robh@kernel.org>
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NRob Herring <robh@kernel.org>

Add fwnode_device_is_available() to tell whether the device corresponding
to a certain fwnode_handle is available for use.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move firmware specific implementations of the fwnode graph operations to
firmware specific locations.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The device and fwnode property API supports Devicetree, ACPI and pset
properties. The implementation of this functionality for each firmware
type was embedded in the fwnode property core. Move it out to firmware
type specific locations, making it easier to maintain.

Depends-on: ("of: Move OF property and graph API from base.c to property.c")
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>