linux-toradex.git/drivers/of/base.c, branch v3.15-rc7

of: make of_update_property() usable earlier in the boot process

2014-05-14T14:27:36+00:00

Commit 75b57ecf9d1d1e17d099ab13b8f48e6e038676be ('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
[] (unwind_backtrace) from [] (show_stack+0x10/0x14)
[] (show_stack) from [] (dump_stack+0x84/0x94)
[] (dump_stack) from [] (warn_slowpath_common+0x6c/0x88)
[] (warn_slowpath_common) from [] (warn_slowpath_fmt+0x30/0x40)
[] (warn_slowpath_fmt) from [] (kernfs_remove_by_name_ns+0x80/0x88)
[] (kernfs_remove_by_name_ns) from [] (of_update_property+0xc0/0xf0)
[] (of_update_property) from [] (mvebu_timer_and_clk_init+0xfc/0x194)
[] (mvebu_timer_and_clk_init) from [] (start_kernel+0x218/0x350)
[] (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 : []    lr : []    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
[] (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: Thomas Petazzoni 
Fixes: 75b57ecf9d1d ("of: Make device nodes kobjects so they show up in sysfs")
Signed-off-by: Grant Likely

of: Clean up of_update_property

2014-04-15T20:21:22+00:00

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: Guenter Roeck 
Signed-off-by: Rob Herring

Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

2014-04-04T16:50:07+00:00

Pull media updates from Mauro Carvalho Chehab:
 "The main set of series of patches for media subsystem, including:
   - document RC sysfs class
   - added an API to setup scancode to allow waking up systems using the
     Remote Controller
   - add API for SDR devices.  Drivers are still on staging
   - some API improvements for getting EDID data from media
     inputs/outputs
   - new DVB frontend driver for drx-j (ATSC)
   - one driver (it913x/it9137) got removed, in favor of an improvement
     on another driver (af9035)
   - added a skeleton V4L2 PCI driver at documentation
   - added a dual flash driver (lm3646)
   - added a new IR driver (img-ir)
   - added an IR scancode decoder for the Sharp protocol
   - some improvements at the usbtv driver, to allow its core to be
     reused.
   - added a new SDR driver (rtl2832u_sdr)
   - added a new tuner driver (msi001)
   - several improvements at em28xx driver to fix PM support, device
     removal and to split the V4L2 specific bits into a separate
     sub-driver
   - one driver got converted to videobuf2 (s2255drv)
   - the e4000 tuner driver now follows an improved binding model
   - some fixes at V4L2 compat32 code
   - several fixes and enhancements at videobuf2 code
   - some cleanups at V4L2 API documentation
   - usual driver enhancements, new board additions and misc fixups"

[ NOTE! This merge effective drops commit 4329b93b283c ("of: Reduce
  indentation in of_graph_get_next_endpoint").

  The of_graph_get_next_endpoint() function was moved and renamed by
  commit fd9fdb78a9bf ("[media] of: move graph helpers from
  drivers/media/v4l2-core to drivers/of").  It was originally called
  v4l2_of_get_next_endpoint() and lived in the file
  drivers/media/v4l2-core/v4l2-of.c.

  In that original location, it was then fixed to support empty port
  nodes by commit b9db140c1e46 ("[media] v4l: of: Support empty port
  nodes"), and that commit clashes badly with the dropped "Reduce
  intendation" commit.  I had to choose one or the other, and decided
  that the "Support empty port nodes" commit was more important ]

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (426 commits)
  [media] em28xx-dvb: fix PCTV 461e tuner I2C binding
  Revert "[media] em28xx-dvb: fix PCTV 461e tuner I2C binding"
  [media] em28xx: fix PCTV 290e LNA oops
  [media] em28xx-dvb: fix PCTV 461e tuner I2C binding
  [media] m88ds3103: fix bug on .set_tone()
  [media] saa7134: fix WARN_ON during resume
  [media] v4l2-dv-timings: add module name, description, license
  [media] videodev2.h: add parenthesis around macro arguments
  [media] saa6752hs: depends on CRC32
  [media] si4713: fix Kconfig dependencies
  [media] Sensoray 2255 uses videobuf2
  [media] adv7180: free an interrupt on failure paths in init_device()
  [media] e4000: make VIDEO_V4L2 dependency optional
  [media] af9033: Don't export functions for the hardware filter
  [media] af9035: use af9033 PID filters
  [media] af9033: implement PID filter
  [media] rtl2832_sdr: do not use dynamic stack allocation
  [media] e4000: fix 32-bit build error
  [media] em28xx-audio: make sure audio is unmuted on open()
  [media] DocBook media: v4l2_format_sdr was renamed to v4l2_sdr_format
  ...

Merge tag 'dt-for-linus' of git://git.secretlab.ca/git/linux

2014-04-02T21:27:15+00:00

Pull devicetree changes from Grant Likely:
 "Updates to devicetree core code.  This branch contains the following
  notable changes:

   - add reserved memory binding
   - make struct device_node a kobject and remove legacy
     /proc/device-tree
   - ePAPR conformance fixes
   - update in-kernel DTC copy to version v1.4.0
   - preparatory changes for dynamic device tree overlays
   - minor bug fixes and documentation changes

  The most significant change in this branch is the conversion of struct
  device_node to be a kobject that is exposed via sysfs and removal of
  the old /proc/device-tree code.  This simplifies the device tree
  handling code and tightens up the lifecycle on device tree nodes.

  [updated: added fix for dangling select PROC_DEVICETREE]"

* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux: (29 commits)
  dt: Remove dangling "select PROC_DEVICETREE"
  of: Add support for ePAPR "stdout-path" property
  of: device_node kobject lifecycle fixes
  of: only scan for reserved mem when fdt present
  powerpc: add support for reserved memory defined by device tree
  arm64: add support for reserved memory defined by device tree
  of: add missing major vendors
  of: add vendor prefix for SMSC
  of: remove /proc/device-tree
  of/selftest: Add self tests for manipulation of properties
  of: Make device nodes kobjects so they show up in sysfs
  arm: add support for reserved memory defined by device tree
  drivers: of: add support for custom reserved memory drivers
  drivers: of: add initialization code for dynamic reserved memory
  drivers: of: add initialization code for static reserved memory
  of: document bindings for reserved-memory nodes
  Revert "of: fix of_update_property()"
  kbuild: dtbs_install: new make target
  ARM: mvebu: Allows to get the SoC ID even without PCI enabled
  of: Allows to use the PCI translator without the PCI core
  ...

Merge tag 'staging-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

2014-04-01T23:45:00+00:00

Pull staging driver updates from Greg KH:
 "Here's the huge drivers/staging/ update for 3.15-rc1.

  Loads of cleanup fixes, a few drivers removed, and some new ones
  added.

  All have been in linux-next for a while"

* tag 'staging-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1375 commits)
  staging: xillybus: XILLYBUS_PCIE depends on PCI_MSI
  staging: xillybus: Added "select CRC32" for XILLYBUS in Kconfig
  staging: comedi: poc: remove obsolete driver
  staging: unisys: replace kzalloc/kfree with UISMALLOC/UISFREE
  staging: octeon-usb: prevent memory corruption
  staging: usbip: fix line over 80 characters
  staging: usbip: fix quoted string split across lines
  Staging: unisys: Remove RETINT macro
  Staging: unisys: Remove FAIL macro
  Staging: unisys: Remove RETVOID macro
  Staging: unisys: Remove RETPTR macro
  Staging: unisys: Remove RETBOOL macro
  Staging: unisys: Remove FAIL_WPOSTCODE_1 macro
  Staging: unisys: Cleanup macros to get rid of goto statements
  Staging: unisys: include: Remove unused macros from timskmod.h
  staging: dgap: fix the rest of the checkpatch warnings in dgap.c
  Staging: bcm: Remove unnecessary parentheses
  staging: wlags49_h2: Delete unnecessary braces
  staging: wlags49_h2: Do not use assignment in if condition
  staging: wlags49_h2: Enclose macro in a do-while loop
  ...

of: Add support for ePAPR "stdout-path" property

2014-03-28T15:17:23+00:00

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: Grant Likely

Merge remote-tracking branches 'regulator/topic/doc', 'regulator/topic/enable', 'regulator/topic/fan53555', 'regulator/topic/fixed', 'regulator/topic/gpio', 'regulator/topic/lp3971', 'regulator/topic/lp872x' and 'regulator/topic/max14577' into regulator-next

2014-03-26T16:57:57+00:00

of: device_node kobject lifecycle fixes

2014-03-19T14:58:40+00:00

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: Pantelis Antoniou 
[grant.likely: moved of_node_init() calls, fixed up locking, and
               dropped __of_populate() hunks]
Signed-off-by: Grant Likely

of: remove /proc/device-tree

2014-03-11T20:48:32+00:00

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: Grant Likely 
Cc: Rob Herring 
Cc: Benjamin Herrenschmidt 
Cc: David S. Miller 
Cc: Nathan Fontenot 
Cc: Pantelis Antoniou

of: Make device nodes kobjects so they show up in sysfs

2014-03-11T20:48:26+00:00

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: Grant Likely 
Tested-by: Sascha Hauer 
Cc: Rob Herring 
Cc: Benjamin Herrenschmidt 
Cc: David S. Miller 
Cc: Nathan Fontenot 
Cc: Pantelis Antoniou