Including:
 - Fixup outdated kernel-doc paths
 - Slightly too short title underline
 - Some typos
Signed-off-by: NAndres Rodriguez <andresx7@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Postpone calling virt_to_page() translation on memory locations not
guaranteed to be backed by a struct page.  Try first to map memory from
the device coherent memory pool, then perform translation if that fails.

On some architectures, specifically SH when configured with the SPARSEMEM
memory model, assuming a struct page is always assigned to a memory
address lead to unexpected hangs during the virtual to page address
translation. This patch fixes that specific issue but applies in the
general case too.
Suggested-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NJacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The use of "correctly mapped" here is misleading, since it can give the
wrong expectation in the case that the memory *should* have been mapped
from the per-device pool, but doing so failed for other reasons.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

__highest_present_section_nr is a more strict boundary than
NR_MEM_SECTIONS.  So checking __highest_present_section_nr directly is
enough.

Link: http://lkml.kernel.org/r/20180330032044.21647-1-richard.weiyang@gmail.comSigned-off-by: NWei Yang <richard.weiyang@gmail.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

During memory hotplugging we traverse struct pages three times:

1. memset(0) in sparse_add_one_section()
2. loop in __add_section() to set do: set_page_node(page, nid); and
   SetPageReserved(page);
3. loop in memmap_init_zone() to call __init_single_pfn()

This patch removes the first two loops, and leaves only loop 3.  All
struct pages are initialized in one place, the same as it is done during
boot.

The benefits:

 - We improve memory hotplug performance because we are not evicting the
   cache several times and also reduce loop branching overhead.

 - Remove condition from hotpath in __init_single_pfn(), that was added
   in order to fix the problem that was reported by Bharata in the above
   email thread, thus also improve performance during normal boot.

 - Make memory hotplug more similar to the boot memory initialization
   path because we zero and initialize struct pages only in one
   function.

 - Simplifies memory hotplug struct page initialization code, and thus
   enables future improvements, such as multi-threading the
   initialization of struct pages in order to improve hotplug
   performance even further on larger machines.

[pasha.tatashin@oracle.com: v5]
  Link: http://lkml.kernel.org/r/20180228030308.1116-7-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180215165920.8570-7-pasha.tatashin@oracle.comSigned-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: NIngo Molnar <mingo@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

During memory hotplugging the probe routine will leave struct pages
uninitialized, the same as it is currently done during boot.  Therefore,
we do not want to access the inside of struct pages before
__init_single_page() is called during onlining.

Because during hotplug we know that pages in one memory block belong to
the same numa node, we can skip the checking.  We should keep checking
for the boot case.

[pasha.tatashin@oracle.com: s/register_new_memory()/hotplug_memory_register()]
  Link: http://lkml.kernel.org/r/20180228030308.1116-6-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180215165920.8570-6-pasha.tatashin@oracle.comSigned-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NIngo Molnar <mingo@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When memory is hotplugged pages_correctly_reserved() is called to verify
that the added memory is present, this routine traverses through every
struct page and verifies that PageReserved() is set.  This is a slow
operation especially if a large amount of memory is added.

Instead of checking every page, it is enough to simply check that the
section is present, has mapping (struct page array is allocated), and
the mapping is online.

In addition, we should not excpect that probe routine sets flags in
struct page, as the struct pages have not yet been initialized.  The
initialization should be done in __init_single_page(), the same as
during boot.

Link: http://lkml.kernel.org/r/20180215165920.8570-5-pasha.tatashin@oracle.comSigned-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using this helper allows us to avoid the in-kernel calls to the
sys_unshare() syscall. The ksys_ prefix denotes that this function is meant
as a drop-in replacement for the syscall. In particular, it uses the same
calling convention as sys_unshare().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Using this helper allows us to avoid the in-kernel calls to the sys_chdir()
syscall. The ksys_ prefix denotes that this function is meant as a drop-in
replacement for the syscall. In particular, it uses the same calling
convention as sys_chdir().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Using this helper allows us to avoid the in-kernel calls to the
sys_chroot() syscall. The ksys_ prefix denotes that this function is
meant as a drop-in replacement for the syscall. In particular, it uses the
same calling convention as sys_chroot().

In the near future, the fs-external callers of ksys_chroot() should be
converted to use kern_path()/set_fs_root() directly. Then ksys_chroot()
can be moved within sys_chroot() again.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Using this helper allows us to avoid the in-kernel calls to the sys_mount()
syscall. The ksys_ prefix denotes that this function is meant as a drop-in
replacement for the syscall. In particular, it uses the same calling
convention as sys_mount().

In the near future, all callers of ksys_mount() should be converted to call
do_mount() directly.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

The check for the .coredump() callback in coredump_store() is
redundant. It is already assured the device driver implements
the callback upon creating the coredump sysfs entry.
Signed-off-by: NArend van Spriel <aspriel@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some devices have an optimization in place to enable the firmware to
be retaineed during a system reboot, so after reboot the device can skip
requesting and loading the firmware. This can save up to 1s in load
time. The mt7601u 802.11 device happens to be such a device.

When these devices retain the firmware on a reboot and then suspend
they can miss looking for the firmware on resume. To help with this we
need a way to cache the firmware when such an optimization has taken
place.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When the sysctl knob is used ignore the fallback mechanism we pr_info_once()
to ensure its noted the knob was used. The print incorrectly states its a
debugfs knob, its a sysctl knob, so correct this typo.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Several frameworks - clk, gpio, phy, pmw, etc. - maintain
lookup tables for describing connections and provide custom
API for handling them. This introduces a single generic
lookup table and API for the connections.

The motivation for this commit is centralizing the
connection lookup, but the goal is to ultimately extract the
connection descriptions also from firmware by using the
fwnode_graph_* functions and other mechanisms that are
available.
Reviewed-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After some other include file changes, fixes:

drivers/base/firmware_loader/fallback.c: In function 'map_fw_priv_pages':
drivers/base/firmware_loader/fallback.c:232:2: error: implicit declaration of function 'vunmap'; did you mean 'kunmap'? [-Werror=implicit-function-declaration]
  vunmap(fw_priv->data);
  ^~~~~~
  kunmap
drivers/base/firmware_loader/fallback.c:233:18: error: implicit declaration of function 'vmap'; did you mean 'kmap'? [-Werror=implicit-function-declaration]
  fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
                  ^~~~
                  kmap
drivers/base/firmware_loader/fallback.c:233:16: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
  fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
                ^
drivers/base/firmware_loader/fallback.c: In function 'firmware_loading_store':
drivers/base/firmware_loader/fallback.c:274:4: error: implicit declaration of function 'vfree'; did you mean 'kvfree'? [-Werror=implicit-function-declaration]
    vfree(fw_priv->pages);
    ^~~~~
    kvfree
drivers/base/firmware_loader/fallback.c: In function 'fw_realloc_pages':
drivers/base/firmware_loader/fallback.c:405:15: error: implicit declaration of function 'vmalloc'; did you mean 'kvmalloc'? [-Werror=implicit-function-declaration]
   new_pages = vmalloc(new_array_size * sizeof(void *));
               ^~~~~~~
               kvmalloc
drivers/base/firmware_loader/fallback.c:405:13: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
   new_pages = vmalloc(new_array_size * sizeof(void *));
             ^
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

request_firmware_into_buf() explicitly disables the firmware cache,
meanwhile the firmware cache cannot be used when request_firmware_nowait()
is used without the uevent. Enforce a sanity check for this to avoid future
issues undocumented behaviours should misuses of the firmware cache
happen later.

One of the reasons we want to enforce this is the firmware cache is
used for helping with suspend/resume, and if incompatible calls use it
they can stall suspend.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a helper to check if the firmware cache is already setup for a device.
This will be used later.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently fw_add_devm_name() returns 1 if the firmware cache
was already set. This makes it complicated for us to check for
correctness. It is actually non-fatal if the firmware cache
is already setup, so just return 0, and simplify the checkers.

fw_add_devm_name() adds device's name onto the devres for the
device so that prior to suspend we cache the firmware onto memory,
so that on resume the firmware is reliably available. We never
were checking for success for this call though, meaning in some
really rare cases we my have never setup the firmware cache for
a device, which could in turn make resume fail.

This is all theoretical, no known issues have been reported.
This small issue has been present way since the addition of the
devres firmware cache names on v3.7.

Fixes: f531f05a ("firmware loader: store firmware name into devres list")
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reflects much clearer what is being done.
While at it, kdoc'ify it.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

You currently need four different kernel builds to test the firmware
API fully. By adding a proc knob to force disable the fallback mechanism
completely we are able to reduce the amount of kernels you need built
to test the firmware API down to two.
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently one requires to test four kernel configurations to test the
firmware API completely:

0)
  CONFIG_FW_LOADER=y

1)
  o CONFIG_FW_LOADER=y
  o CONFIG_FW_LOADER_USER_HELPER=y

2)
  o CONFIG_FW_LOADER=y
  o CONFIG_FW_LOADER_USER_HELPER=y
  o CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y

3) When CONFIG_FW_LOADER=m the built-in stuff is disabled, we have
   no current tests for this.

We can reduce the requirements to three kernel configurations by making
fw_config.force_sysfs_fallback a proc knob we flip on off. For kernels that
disable CONFIG_IKCONFIG_PROC this can also enable one to inspect if
CONFIG_FW_LOADER_USER_HELPER_FALLBACK was enabled at build time by checking
the proc value at boot time.
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This will make it much easier to manage as we manage to
keep trimming componnents down into their own files to more
easily manage and maintain this codebase.
Suggested-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The firmware fallback code is optional. Split that code out to help
distinguish the fallback functionlity from othere core firmware loader
features. This should make it easier to maintain and review code
changes.

The reason for keeping the configuration onto a table which is built-in
if you enable firmware loading is so that we can later enable the kernel
after subsequent patches to tweak this configuration, even if the
firmware loader is modular.

This introduces no functional changes.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The timeout is a fallback construct, so we can just stuff the
timeout configuration under struct firmware_fallback_config.

While at it, add a few helpers which vets the use of getting or
setting the timeout as an int. The main use of the timeout is
to set a timeout for completion, and that is used as an unsigned
long. There a few cases however where it makes sense to get or
set the timeout as an int, the helpers annotate these use cases
have been properly vetted for.
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We only use the timeout for the firmware fallback mechanism
except for trying to set the timeout during the cache setup
for resume/suspend. For those cases, setting the timeout should
be a no-op, so just reflect this in code by adding helpers for it.

This change introduces no functional changes.
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

All CONFIG_FW_LOADER_USER_HELPER_FALLBACK really is, is just a bool,
initailized at build time. Define it as such. This simplifies the
logic even further, removing now all explicit #ifdefs around the code.
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

if device_register() returned an error! Always use put_device()
to give up the reference initialized.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

if device_register() returned an error! Always use put_device()
to give up the reference initialized.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

if device_register() returned an error! Always use put_device()
to give up the reference initialized.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Never directly free @dev after calling device_register(), even
if it returned an error! Always use put_device() to give up the
reference initialized.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 452562ab ("base: arch_topology: fix section
mismatch build warnings"). It causes the notifier call hangs in some
use-cases.

In some cases with using maxcpus, some of cpus are booted first and
then the remaining cpus are booted. As an example, some users who want
to realize fast boot up often use the following procedure.

  1) Define all CPUs on device tree (CA57x4 + CA53x4)
  2) Add "maxcpus=4" in bootargs
  3) Kernel boot up with CA57x4
  4) After kernel boot up, CA53x4 is booted from user

When kernel init was finished, CPUFREQ_POLICY_NOTIFIER was not still
unregisterd. This means that "__init init_cpu_capacity_callback()"
will be called after kernel init sequence. To avoid this problem,
it needs to remove __init{,data} annotations by reverting this commit.

Also, this commit was needed to fix kernel compile issue below.
However, this issue was also fixed by another patch: commit 82d8ba71
("arch_topology: Fix section miss match warning due to
free_raw_capacity()") in v4.15 as well.
Whereas commit 452562ab added all the missing __init annotations,
commit 82d8ba71 removed it from free_raw_capacity().

WARNING: vmlinux.o(.text+0x548f24): Section mismatch in reference
from the function init_cpu_capacity_callback() to the variable
.init.text:$x
The function init_cpu_capacity_callback() references
the variable __init $x.
This is often because init_cpu_capacity_callback lacks a __init
annotation or the annotation of $x is wrong.

Fixes: 82d8ba71 ("arch_topology: Fix section miss match warning due to free_raw_capacity()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGaku Inami <gaku.inami.xh@renesas.com>
Reviewed-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The firmware loader code has grown quite a bit over the years.
The practice of stuffing everything we need into one file makes
the code hard to follow.

In order to split the firmware loader code into different components
we must pick a module name and a first object target file. We must
keep the firmware_class name to remain compatible with scripts which
have been relying on the sysfs loader path for years, so the old module
name stays. We can however rename the C file without affecting the
module name.

The firmware_class used to represent the idea that the code was a simple
sysfs firmware loader, provided by the struct class firmware_class.
The sysfs firmware loader used to be the default, today its only the
fallback mechanism.

This only renames the target code then to make emphasis of what the code
does these days. With this change new features can also use a new object
files.
Signed-off-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently when debugfs_create_dir() fails we receive a warning message
that provides no indication as to what was the directory entry that
failed to be created.

Improve the warning message by printing the directory name that failed
in order to help debugging.
Signed-off-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Free map->debugfs_name when debugfs_create_dir() failed to avoid memory
leak.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

When allocating dummy names we need to store a pointer to the string we
allocate so that we don't leak it on free.
Signed-off-by: NMark Brown <broonie@kernel.org>

Since commit 9b947a13 ("regmap: use debugfs even when no device")
allows the usage of regmap debugfs even when there is no device
associated, which causes several warnings like this:

(NULL device *): Failed to create debugfs directory

This happens when the debugfs file name is 'dummy'.

The first dummy debugfs creation works fine, but subsequent creations
fail as they have all the same name.

Disambiguate the 'dummy' debugfs file name by adding a suffix entry,
so that the names become dummy0, dummy1, dummy2, etc.
Signed-off-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

If device_link_add() is invoked multiple times with the same supplier
and consumer combo, it will create the link on first addition and
return a pointer to the already existing link on all subsequent
additions.

The semantics for device_link_del() are quite different, it deletes
the link unconditionally, so multiple invocations are not allowed.

In other words, this snippet ...

    struct device *dev1, *dev2;
    struct device_link *link1, *link2;

    link1 = device_link_add(dev1, dev2, 0);
    link2 = device_link_add(dev1, dev2, 0);

    device_link_del(link1);
    device_link_del(link2);

... causes the following crash:

    WARNING: CPU: 4 PID: 2686 at drivers/base/power/runtime.c:1611 pm_runtime_drop_link+0x40/0x50
    [...]
    list_del corruption, 0000000039b800a4->prev is LIST_POISON2 (00000000ecf79852)
    kernel BUG at lib/list_debug.c:50!

The issue isn't as arbitrary as it may seem:  Imagine a device link
which is added in both the supplier's and the consumer's ->probe hook.
The two drivers can't just call device_link_del() in their ->remove hook
without coordination.

Fix by counting multiple additions and dropping the device link only
when the last addition is unwound.
Signed-off-by: NLukas Wunner <lukas@wunner.de>
[ rjw: Subject ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This makes it easy to grep :wakeup /proc/interrupts.
Suggested-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

regmap_init_mmio_clk allows to specify a clock that needs to be enabled
while accessing the registers.

However, that clock is retrieved through its clock ID, which means it will
lookup that clock based on the current device that registers the regmap,
and, in the DT case, will only look in that device OF node.

This might be problematic if the clock to enable is stored in another node.
Let's add a function that allows to attach a clock that has already been
retrieved to a regmap in order to fix this.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NMark Brown <broonie@kernel.org>