linux-stable.git/drivers/of/base.c, branch linux-4.9.y

of: fix missing kobject init for !SYSFS && OF_DYNAMIC config

2020-04-24T05:59:10+00:00

[ Upstream commit bd82bbf38cbe27f2c65660da801900d71bcc5cc8 ]

The ref counting is broken for OF_DYNAMIC when sysfs is disabled because
the kobject initialization is skipped. Only the properties
add/remove/update should be skipped for !SYSFS config.

Tested-by: Nicolas Pitre 
Reviewed-by: Frank Rowand 
Acked-by: Grant Likely 
Signed-off-by: Rob Herring 
Signed-off-by: Lee Jones 
Signed-off-by: Greg Kroah-Hartman

of: make PowerMac cache node search conditional on CONFIG_PPC_PMAC

2019-11-25T08:52:08+00:00

[ Upstream commit f6707fd6241e483f6fea2caae82d876e422bb11a ]

Cache nodes under the cpu node(s) is PowerMac specific according to the
comment above, so make the code enforce that.

Signed-off-by: Rob Herring 
Signed-off-by: Sasha Levin

of: add helper to lookup compatible child node

2018-12-01T08:44:21+00:00

[ Upstream commit 36156f9241cb0f9e37d998052873ca7501ad4b36 ]

Add of_get_compatible_child() helper that can be used to lookup
compatible child nodes.

Several drivers currently use of_find_compatible_node() to lookup child
nodes while failing to notice that the of_find_ functions search the
entire tree depth-first (from a given start node) and therefore can
match unrelated nodes. The fact that these functions also drop a
reference to the node they start searching from (e.g. the parent node)
is typically also overlooked, something which can lead to use-after-free
bugs.

Signed-off-by: Johan Hovold 
Signed-off-by: Rob Herring 
Signed-off-by: Sasha Levin

OF: Prevent unaligned access in of_alias_scan()

2018-04-29T09:31:57+00:00

commit de96ec2a77c6d06a423c2c495bb4a2f4299f3d9e upstream.

When allocating a struct alias_prop, of_alias_scan() only requested that
it be aligned on a 4 byte boundary. The struct contains pointers which
leads to us attempting 64 bit writes on 64 bit systems, and if the CPU
doesn't support unaligned memory accesses then this causes problems -
for example on some MIPS64r2 CPUs including the "mips64r2-generic" QEMU
emulated CPU it will trigger an address error exception.

Fix this by requesting alignment for the struct alias_prop allocation
matching that which the compiler expects, using the __alignof__ keyword.

Signed-off-by: Paul Burton 
Acked-by: Rob Herring 
Reviewed-by: Grant Likely 
Cc: Frank Rowand 
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14306/
Signed-off-by: Ralf Baechle 
Cc: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

Revert "console: don't prefer first registered if DT specifies stdout-path"

2016-11-11T16:12:37+00:00

This reverts commit 05fd007e4629 ("console: don't prefer first
registered if DT specifies stdout-path").

The reverted commit changes existing behavior on which many ARM boards
rely.  Many ARM small-board-computers, like e.g.  the Raspberry Pi have
both a video output and a serial console.  Depending on whether the user
is using the device as a more regular computer; or as a headless device
we need to have the console on either one or the other.

Many users rely on the kernel behavior of the console being present on
both outputs, before the reverted commit the console setup with no
console= kernel arguments on an ARM board which sets stdout-path in dt
would look like this:

  [root@localhost ~]# cat /proc/consoles
  ttyS0                -W- (EC p a)    4:64
  tty0                 -WU (E  p  )    4:1

Where as after the reverted commit, it looks like this:

  [root@localhost ~]# cat /proc/consoles
  ttyS0                -W- (EC p a)    4:64

This commit reverts commit 05fd007e4629 ("console: don't prefer first
registered if DT specifies stdout-path") restoring the original
behavior.

Fixes: 05fd007e4629 ("console: don't prefer first registered if DT specifies stdout-path")
Link: http://lkml.kernel.org/r/20161104121135.4780-2-hdegoede@redhat.com
Signed-off-by: Hans de Goede 
Cc: Paul Burton 
Cc: Rob Herring 
Cc: Frank Rowand 
Cc: Thorsten Leemhuis 
Cc: Greg Kroah-Hartman 
Cc: Tejun Heo 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

console: don't prefer first registered if DT specifies stdout-path

2016-10-08T01:46:30+00:00

If a device tree specifies a preferred device for kernel console output
via the stdout-path or linux,stdout-path chosen node properties or the
stdout alias then the kernel ought to honor it & output the kernel
console to that device.  As it stands, this isn't the case.  Whilst we
parse the stdout-path properties & set an of_stdout variable from
of_alias_scan(), and use that from of_console_check() to determine
whether to add a console device as a preferred console whilst
registering it, we also prefer the first registered console if no other
has been selected at the time of its registration.

This means that if a console other than the one the device tree selects
via stdout-path is registered first, we will switch to using it & when
the stdout-path console is later registered the call to
add_preferred_console() via of_console_check() is too late to do
anything useful.  In practice this seems to mean that we switch to the
dummy console device fairly early & see no further console output:

    Console: colour dummy device 80x25
    console [tty0] enabled
    bootconsole [ns16550a0] disabled

Fix this by not automatically preferring the first registered console if
one is specified by the device tree.  This allows consoles to be
registered but not enabled, and once the driver for the console selected
by stdout-path calls of_console_check() the driver will be added to the
list of preferred consoles before any other console has been enabled.
When that console is then registered via register_console() it will be
enabled as expected.

Link: http://lkml.kernel.org/r/20160809151937.26118-1-paul.burton@imgtec.com
Signed-off-by: Paul Burton 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: Tejun Heo 
Cc: Sergey Senozhatsky 
Cc: Jiri Slaby 
Cc: Daniel Vetter 
Cc: Ivan Delalande 
Cc: Thierry Reding 
Cc: Borislav Petkov 
Cc: Jan Kara 
Cc: Petr Mladek 
Cc: Joe Perches 
Cc: Greg Kroah-Hartman 
Cc: Rob Herring 
Cc: Frank Rowand 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

of: Add array read functions with min/max size limits

2016-09-15T13:33:01+00:00

Add a new set of array reading functions that take a minimum and
maximum size limit and will fail if the property size is not within
the size limits. This makes it more convenient for drivers that
use variable-size DT arrays which must be bounded at both ends -
data must be at least N entries but must not overflow the array
it is being copied into. It is also more efficient than making this
functionality out of existing public functions and avoids duplication.

The existing array functions have been left in the API, since there
are a very large number of clients of those functions and their
existing functionality is still useful. This avoids turning a small
API improvement into a major kernel rework.

The old functions have been turned into mininmal static inlines calling
the new functions. The old functions had no upper limit on the actual
size of the dts entry, to preserve this functionality rather than keeping
two near-identical implementations, if the new function is called with
max=0 there is no limit on the size of the dts entry but only the min
number of elements are read.

Signed-off-by: Richard Fitzgerald 
Signed-off-by: Rob Herring

of: Make of_find_property_value_of_size take a length range

2016-09-15T13:32:57+00:00

In preparation for adding variable-length array reads, change
of_find_property_value_of_size so that it takes an optional
maximum length. If the maximum is passed as 0, the behaviour is
unchanged and it will return a property if it's >= the requested
minimum length. If maximum is non-zero it will only return a
property whose length is min <= l <= max.

Signed-off-by: Richard Fitzgerald 
Signed-off-by: Rob Herring

of: fix reference counting in of_graph_get_endpoint_by_regs

2016-08-15T16:15:05+00:00

The called of_graph_get_next_endpoint() already decrements the refcount
of the prev node, so it is wrong to do it again in the calling function.

Use the for_each_endpoint_of_node() helper to interate through the
endpoint OF nodes, which already does the right thing and simplifies
the code a bit.

Fixes: 8ccd0d0ca041
(of: add helper for getting endpoint node of specific identifiers)
Cc: stable@vger.kernel.org
Reported-by: David Jander 
Signed-off-by: Lucas Stach 
Acked-by: Philipp Zabel 
Signed-off-by: Rob Herring

of: Delete an unnecessary check before the function call "of_node_put"

2016-08-09T17:36:27+00:00

The of_node_put() function tests whether its argument is NULL
and then returns immediately.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring 
Signed-off-by: Rob Herring