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440787 commits

Author SHA1 Message Date
Frank Praznik
914c578391 HID: sony: Fix Sixaxis cable state detection
Byte 31 of the Sixaxis report can change depending on whether or not the
controller is rumbling.  Using bit 3 is the only reliable way to detect the
state of the cable regardless of rumble activity.

Signed-off-by: Frank Praznik <frank.praznik@oh.rr.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-04-01 18:44:06 +02:00
Petri Gynther
4522643aa9 HID: uhid: Add UHID_CREATE2 + UHID_INPUT2
UHID_CREATE2:
HID report descriptor data (rd_data) is an array in struct uhid_create2_req,
instead of a pointer. Enables use from languages that don't support pointers,
e.g. Python.

UHID_INPUT2:
Data array is the last field of struct uhid_input2_req. Enables userspace to
write only the required bytes to kernel (ev.type + ev.u.input2.size + the part
of the data array that matters), instead of the entire struct uhid_input2_req.

Note:
UHID_CREATE2 increases the total size of struct uhid_event slightly, thus
increasing the size of messages that are queued for userspace. However, this
won't affect the userspace processing of these events.

[Jiri Kosina <jkosina@suse.cz>: adjust to hid_get_raw_report() and
				hid_output_raw_report() API changes]

Signed-off-by: Petri Gynther <pgynther@google.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-04-01 18:27:33 +02:00
Miklos Szeredi
bd42998a6b ext4: add cross rename support
Implement RENAME_EXCHANGE flag in renameat2 syscall.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-04-01 17:08:44 +02:00
Miklos Szeredi
bd1af145b9 ext4: rename: split out helper functions
Cross rename (exchange source and dest) will need to call some of these
helpers for both source and dest, while overwriting rename currently only
calls them for one or the other.  This also makes the code easier to
follow.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-04-01 17:08:44 +02:00
Miklos Szeredi
0d7d5d678b ext4: rename: move EMLINK check up
Move checking i_nlink from after ext4_get_first_dir_block() to before.  The
check doesn't rely on the result of that function and the function only
fails on fs corruption, so the order shouldn't matter.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-04-01 17:08:44 +02:00
Miklos Szeredi
c0d268c366 ext4: rename: create ext4_renament structure for local vars
Need to split up ext4_rename() into helpers but there are too many local
variables involved, so create a new structure.  This also, apparently,
makes the generated code size slightly smaller.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-04-01 17:08:43 +02:00
Miklos Szeredi
da1ce0670c vfs: add cross-rename
If flags contain RENAME_EXCHANGE then exchange source and destination files.
There's no restriction on the type of the files; e.g. a directory can be
exchanged with a symlink.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:43 +02:00
J. Bruce Fields
4fd699ae3f vfs: lock_two_nondirectories: allow directory args
lock_two_nondirectories warned if either of its args was a directory.
Instead just ignore the directory args.  This is needed for locking in
cross rename.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-01 17:08:43 +02:00
Miklos Szeredi
0b3974eb04 security: add flags to rename hooks
Add flags to security_path_rename() and security_inode_rename() hooks.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:43 +02:00
Miklos Szeredi
0a7c3937a1 vfs: add RENAME_NOREPLACE flag
If this flag is specified and the target of the rename exists then the
rename syscall fails with EEXIST.

The VFS does the existence checking, so it is trivial to enable for most
local filesystems.  This patch only enables it in ext4.

For network filesystems the VFS check is not enough as there may be a race
between a remote create and the rename, so these filesystems need to handle
this flag in their ->rename() implementations to ensure atomicity.

Andy writes about why this is useful:

"The trivial answer: to eliminate the race condition from 'mv -i'.

Another answer: there's a common pattern to atomically create a file
with contents: open a temporary file, write to it, optionally fsync
it, close it, then link(2) it to the final name, then unlink the
temporary file.

The reason to use link(2) is because it won't silently clobber the destination.

This is annoying:
 - It requires an extra system call that shouldn't be necessary.
 - It doesn't work on (IMO sensible) filesystems that don't support
hard links (e.g. vfat).
 - It's not atomic -- there's an intermediate state where both files exist.
 - It's ugly.

The new rename flag will make this totally sensible.

To be fair, on new enough kernels, you can also use O_TMPFILE and
linkat to achieve the same thing even more cleanly."

Suggested-by: Andy Lutomirski <luto@amacapital.net> 
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:43 +02:00
Miklos Szeredi
520c8b1650 vfs: add renameat2 syscall
Add new renameat2 syscall, which is the same as renameat with an added
flags argument.

Pass flags to vfs_rename() and to i_op->rename() as well.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:42 +02:00
Miklos Szeredi
bc27027a73 vfs: rename: use common code for dir and non-dir
There's actually very little difference between vfs_rename_dir() and
vfs_rename_other() so move both inline into vfs_rename() which still stays
reasonably readable.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:42 +02:00
Miklos Szeredi
de22a4c372 vfs: rename: move d_move() up
Move the d_move() in vfs_rename_dir() up, similarly to how it's done in
vfs_rename_other().  The next patch will consolidate these two functions
and this is the only structural difference between them.

I'm not sure if doing the d_move() after the dput is even valid.  But there
may be a logical explanation for that.  But moving the d_move() before the
dput() (and the mutex_unlock()) should definitely not hurt.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:42 +02:00
Miklos Szeredi
44b1d53043 vfs: add d_is_dir()
Add d_is_dir(dentry) helper which is analogous to S_ISDIR().

To avoid confusion, rename d_is_directory() to d_can_lookup().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:41 +02:00
David Woodhouse
7713ec066a iommu/vt-d: Fix error handling in ANDD processing
If we failed to find an ACPI device to correspond to an ANDD record, we
would fail to increment our pointer and would just process the same record
over and over again, with predictable results.

Turn it from a while() loop into a for() loop to let the 'continue' in
the error paths work correctly.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2014-04-01 14:58:38 +01:00
Taras Kondratiuk
41b5368f31 ARM: kprobes-test: Workaround GAS .align bug
By default if no fill symbol is given to .align directive in a code
section it fills gap with NOPs. If previous fragment is not
instruction-aligned, additional pre-alignment is done by zero bytes
before NOPs. These zero bytes are marked as data by special symbol $d in
symbol table. Unfortunately GAS assumes that there is only code in the
code section so it "puts back" code symbol $a at the end of this
pre-alignment. So if there is some data after alignment it will be
interpreted as code and will be swapped back to LE for BE8 system during
a final linking.

If explicit fill value is given to .align, the NOP-padding code is
skipped and symbol table does not get messed-up.

So the workaround for this issue:
Use explicit fill value if data should be aligned in the code section.

Acked-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
2014-04-01 16:48:27 +03:00
Ben Dooks
3b86ee7a69 ARM: kprobes-test: use <asm/opcodes.h> for Thumb instruction building
The kprobes test will build certain instructions incorrectly if building
big endian as .word/.short output gets endian-swapped by the linker.
Change to using <asm/opcodes.h> and __inst_thumbXX() to produce instructions.

Acked-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
2014-04-01 16:48:26 +03:00
Ben Dooks
af886d2dfd ARM: kprobes-test: use <asm/opcodes.h> for ARM instruction building
The kprobes test will build certain instructions incorrectly if building
big endian as .word output gets endian-swapped by the linker. Change to
using <asm/opcodes.h> and __inst_arm() to produce instructions.

Acked-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
[taras.kondratiuk@linaro.org: fixed unsupported coprocessor instructions]
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
2014-04-01 16:48:24 +03:00
Ben Dooks
4712e17aa4 ARM: kprobes-test: use <asm/opcodes.h> for instruction accesses
Ensure we read instructions in the correct endian-ness by using
the <asm/opcodes.h> helper to transform them as necessary.

Acked-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
[taras.kondratiuk@linaro.org: fix next_instruction() function]
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
2014-04-01 16:48:23 +03:00
Ben Dooks
888be25402 ARM: probes: fix instruction fetch order with <asm/opcodes.h>
If we are running BE8, the data and instruction endianness do not
match, so use <asm/opcodes.h> to correctly translate memory accesses
into ARM instructions.

Acked-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
[taras.kondratiuk@linaro.org: fixed Thumb instruction fetch order]
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
2014-04-01 16:45:19 +03:00
Ingo Molnar
b8c89c6a0d Fix the code to tell when a CMCI storm ends by actually
looking at the machine check banks when we poll while
 interrupts are disabled.
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Merge tag 'please-pull-cmci-storm' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras into x86/urgent

Pull RAS/CMCI storm code fix from Tony Luck:

 "Fix the code to tell when a CMCI storm ends by actually
  looking at the machine check banks when we poll while
  interrupts are disabled."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-01 15:13:16 +02:00
Maciej W. Rozycki
023de4a09f x86/apic: Reinstate error IRQ Pentium erratum 3AP workaround
A change introduced with commit 60283df7ac
("x86/apic: Read Error Status Register correctly") removed a read from the
APIC ESR register made before writing to same required to retrieve the
correct error status on Pentium systems affected by the 3AP erratum[1]:

	"3AP. Writes to Error Register Clears Register

	PROBLEM: The APIC Error register is intended to only be read.
	If there is a write to this register the data in the APIC Error
	register will be cleared and lost.

	IMPLICATION: There is a possibility of clearing the Error
	register status since the write to the register is not
	specifically blocked.

	WORKAROUND: Writes should not occur to the Pentium processor
	APIC Error register.

	STATUS: For the steppings affected see the Summary Table of
	Changes at the beginning of this section."

The steppings affected are actually: B1, B3 and B5.

To avoid this information loss this change avoids the write to
ESR on all Pentium systems where it is actually never needed;
in Pentium processor documentation ESR was noted read-only and
the write only required for future architectural
compatibility[2].

The approach taken is the same as in lapic_setup_esr().

References:

	[1] "Pentium Processor Family Developer's Manual", Intel Corporation,
	    1997, order number 241428-005, Appendix A "Errata and S-Specs for the
	    Pentium Processor Family", p. A-92,

	[2] "Pentium Processor Family Developer's Manual, Volume 3: Architecture
	    and Programming Manual", Intel Corporation, 1995, order number
	    241430-004, Section 19.3.3. "Error Handling In APIC", p. 19-33.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1404011300010.27402@eddie.linux-mips.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-01 14:59:43 +02:00
Stephen Warren
3534b842a8 ASoC: tlv320aic23: add an of_match table
Add a device tree match table. This serves to make the driver's support
of device tree more explicit. Perhaps the fallback for DT matching to
using the i2c_device_id table will go away one day, since it fails in
face of devices from different vendors with the same name.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 13:34:22 +01:00
Thierry Reding
2ae69a4604 pwm: pxa: Constify OF match table
The table is never modified and all OF functions that use it take a
const struct of_device_id *.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-04-01 14:06:43 +02:00
Thierry Reding
fdec4f7271 pwm: pxa: Fix typo "pwm" -> "PWM"
Being an abbreviation, PWM should always be capitalized in prose.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-04-01 14:04:59 +02:00
Thierry Reding
f409cd3833 Revert "pwm: pxa: Use of_match_ptr()"
This reverts commit 8468949cdd.

The OF match table dummy for non-OF configurations cannot be removed
because it is still used by the pxa_pwm_get_id_dt() function.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-04-01 14:01:32 +02:00
Stephen Warren
2951f93f43 ASoC: max98090: add an of_match table
Add a device tree match table. This serves to make the driver's support
of device tree more explicit. Perhaps the fallback for DT matching to
using the i2c_device_id table will go away one day, since it fails in
face of devices from different vendors with the same name.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 12:46:12 +01:00
Stephen Warren
c31b0cb1f1 ASoC: alc5632: add an of_match table
Add a device tree match table. This serves to make the driver's support
of device tree more explicit. Perhaps the fallback for DT matching to
using the i2c_device_id table will go away one day, since it fails in
face of devices from different vendors with the same name.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 12:39:44 +01:00
Stephen Warren
e3efe3bedb ASoC: alc5632: fix uninit var in alc5632_probe()
alc5632_probe() returns ret, yet it is not initialized or set anywhere.
This ends up causing the function to appear to fail, and audio not to
work on the Toshiba AC100, with my compiler at least.

This function used to set ret in all cases, but recent cleanup removed
that.

Fixes: 5d6be5aa6b ("ASoC: codec: Simplify ASoC probe code.")
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 12:39:26 +01:00
Gerald Schaefer
9f0128f9e7 s390/sclp: add timeout for queued requests
This patch adds a timeout option for queued requests and introduces
sclp_sync_request_timeout() to use this timer. With this, blocking the
system too long, e.g. during an SE reboot, can be avoided in critical
situations like CPU and memory hotplug.
Since there is no way to cancel a running request, this timeout only
applies to queued requests that have not yet been started.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-04-01 13:25:26 +02:00
Daeseok Youn
a7a037c837 regmap: adds missing braces in regmap_init()
It need to add curly braces because the inner for "if" has
two statements.

coccicheck says:
 drivers/base/regmap/regmap.c:765:2-44:
code aligned with following code on line 766

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 12:09:08 +01:00
Jianyu Zhan
5f0985bb11 mm/slab.c: cleanup outdated comments and unify variables naming
As time goes, the code changes a lot, and this leads to that
some old-days comments scatter around , which instead of faciliating
understanding, but make more confusion. So this patch cleans up them.

Also, this patch unifies some variables naming.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2014-04-01 13:49:25 +03:00
Joonsoo Kim
24f870d8f0 slab: fix wrongly used macro
commit 'slab: restrict the number of objects in a slab' uses
__builtin_constant_p() on #if macro. It is wrong usage of builtin
function, but it is compiled on x86 without any problem, so I can't
find it before 0 day build system find it.

This commit fixes the situation by using KMALLOC_MIN_SIZE, instead of
KMALLOC_SHIFT_LOW. KMALLOC_SHIFT_LOW is parsed to ilog2() on some
architecture and this ilog2() uses __builtin_constant_p() and results in
the problem. This problem would disappear by using KMALLOC_MIN_SIZE,
since it is just constant.

Tested-by: David Rientjes <rientjes@google.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2014-04-01 13:38:04 +03:00
Mika Westerberg
d16a5aa9e8 pwm: add support for Intel Low Power Subsystem PWM
Add support for Intel Low Power I/O subsystem PWM controllers found on
Intel BayTrail SoC.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Chew, Kean Ho <kean.ho.chew@intel.com>
Signed-off-by: Chang, Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com>
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-04-01 12:03:40 +02:00
Thomas Gleixner
b1d8e431bd can: c_can: Avoid led toggling for every packet.
There is no point to toggle the RX led for every packet. Especially if
we have a full FIFO we want to avoid everything we can.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:55:02 +02:00
Thomas Gleixner
5a7513adab can: c_can: Simplify TX interrupt cleanup
The function loads the message object from the hardware to get the
payload length. The previous patch stores that information in an
array, so we can avoid the hardware access.

Remove the hardware access and move the led toggle outside of the
spinlocked region. Toggle the led only once when at least one packet
has been received.

Binary size shrinks along with the code

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:55:01 +02:00
Thomas Gleixner
9024700854 can: c_can: Store dlc private
We can avoid the HW access in TX cleanup path for retrieving the DLC
of the sent package if we store the DLC in a private array.

Ideally this should be handled in the can_echo_skb functions, but I
leave that exercise to the CAN folks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:55:01 +02:00
Thomas Gleixner
c0a9f4d396 can: c_can: Reduce register access
commit 4ce78a838c (can: c_can: Speed up rx_poll function) hyped a
performance improvement by reducing the access to the interrupt
pending register from a dual 16 bit to a single 16 bit access. Wow!

Thereby it crippled the driver to cast the 16 msg objects in stone,
which is completly braindead as contemporary hardware has up to 128
message objects. Supporting larger object buffers is a major surgery,
but it'd be definitely worth it especially as the driver does not
support HW message filtering ....

The logic of the "FIFO" implementation is to split the FIFO in half.

For the lower half we read the buffers and clear the interrupt pending
bit, but keep the newdat bit set, so the HW will queue above those
buffers.

When we read out the last low buffer then we reenable all the low half
buffers by clearing the newdat bit.

The upper half buffers clear the newdat and the interrupt pending bit
right away as we know that the lower half bits are clear and give us a
headstart against the hardware.

Now the implementation is:

    transfer_message_object()
    read_object_and_put_into_skb();

    if (obj < END_OF_LOW_BUF)
       clear_intpending(obj)
    else if (obj > END_OF_LOW_BUF)
       clear_intpending_and_newdat(obj)
    else if (obj == END_OF_LOW_BUF)
       clear_newdat_of_all_low_objects()

The hardware allows to avoid most of the mess simply because we can
tell the transfer_message_object() function to clear bits right away.

So we can be clever and do:

   if (obj <= END_OF_LOW_BUF)
      ctrl = TRANSFER_MSG | CLEAR_INTPND;
   else
      ctrl = TRANSFER_MSG | CLEAR_INTPND | CLEAR_NEWDAT;

    transfer_message_object(ctrl)
    read_object_and_put_into_skb();

    if (obj == END_OF_LOW_BUF)
       clear_newdat_of_all_low_objects()

So we save a complete control operation on all message objects except
the one which is the end of the low buffer. That's a few micro seconds
per object.

I'm not adding a boasting profile to that, simply because it's self
explaining.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject and commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:55:01 +02:00
Thomas Gleixner
520f570c43 can: c_can: Make the code readable
If every other line contains line breaks, that's a clear sign for
indentation level madness. Split out the inner loop and move the code
to a separate function. gcc creates slightly worse code for that, but
we'll fix that in the next step.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:55:00 +02:00
Thomas Gleixner
bf88a20611 can: c_can: Provide protection in the xmit path
The network core does not serialize the access to the hardware. The
xmit related code lets the following happen:

CPU0 	     	       CPU1
interrupt()
 do_poll()
   c_can_do_tx()
    Fiddle with HW and	xmit()
    internal data	  Fiddle with HW and
    	     		  internal data

due the complete lack of serialization.

Add proper locking.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:55:00 +02:00
Thomas Gleixner
710c56105d can: c_can: Remove EOB exit
The rx_poll code has the following gem:

	if (msg_ctrl_save & IF_MCONT_EOB)
		return num_rx_pkts;

The EOB bit is the indicator for the hardware that this is the last
configured FIFO object. But this object can contain valid data, if we
manage to free up objects before the overrun case hits.

Now if the code exits due to the EOB bit set, then this buffer is
stale and the interrupt bit and NewDat bit of the buffer are still
set. Results in a nice interrupt storm unless we come into an overrun
situation where the MSGLST bit gets set.

     ksoftirqd/0-3     [000] ..s.    79.124101: c_can_poll: rx_poll: val: 00008001 pend 00008001
     ksoftirqd/0-3     [000] ..s.    79.124176: c_can_poll: rx_poll: val: 00008000 pend 00008000
     ksoftirqd/0-3     [000] ..s.    79.124187: c_can_poll: rx_poll: val: 00008002 pend 00008002
     ksoftirqd/0-3     [000] ..s.    79.124256: c_can_poll: rx_poll: val: 00008000 pend 00008000
     ksoftirqd/0-3     [000] ..s.    79.124267: c_can_poll: rx_poll: val: 00008000 pend 00008000

The amazing thing is that the check of the MSGLST (aka overrun bit)
used to be after the check of the EOB bit. That was "fixed" in commit
5d0f801a2c(can: c_can: Fix RX message handling, handle lost message
before EOB). But the author of this "fix" did not even understand that
the EOB check is broken as well.

Again a simple solution: Remove

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject and commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:59 +02:00
Thomas Gleixner
07c7b6f616 can: c_can: Fix the lost message handling
The lost message handling is broken in several ways.

1) Clearing the message lost flag is done by writing 0 to the
   message control register of the object.

   #define IF_MCONT_CLR_MSGLST    (0 << 14)

   That clears the object buffer configuration in the worst case,
   which results in a loss of the EOB flag. That leaves the FIFO chain
   without a limit and causes a complete lockup of the HW

2) In case that the error skb allocation fails, the code happily
   claims that it handed down a packet. Just an accounting bug, but ....

3) The code adds a lot of pointless overhead to that error case, where
   we need to get stuff done as fast as possible to avoid more packet
   loss.

   - printk an annoying error message
   - reread the object buffer for nothing

Fix is simple again:

  - Use the already known MSGCTRL content and only clear the MSGLST bit
  - Fix the buffer accounting by adding a proper return code
  - Remove the pointless operations

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:59 +02:00
Thomas Gleixner
64f08f2f35 can: c_can: Fix buffer ordering
The buffer handling of c_can has been broken forever. That leads to
message reordering:

ksoftirqd/0-3     [000] ..s.    79.123776: c_can_poll: rx_poll: val: 00007fff
ksoftirqd/0-3     [000] ..s.    79.124101: c_can_poll: rx_poll: val: 00008001

What happens is:

CPU				HW
				queue new packet into obj 16 (0-15 are busy)
read obj 1-15
return because pending is 0
				set pending obj 16 -> pending reg 8000
				queue new packet into obj 1
				set pending obj 1 -> pending reg 8001

So the current algorithmus reads the newest message first, which
violates the ordering rules of CAN.

Add proper handling of that situation by analyzing the contents of the
pending register for gaps.

This does NOT fix the message object corruption which can lead to
interrupt storms. Thats addressed in the next patches.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:58 +02:00
Thomas Gleixner
640916db2b can: c_can: Make it SMP safe
The hardware has two message control interfaces, but the code only uses the
first one. So on SMP the following can be observed:

CPU0 	       	CPU1
rx_poll()
  write IF1	xmit()
		write IF1
  write IF1

That results in corrupted message object configurations. The TX/RX is not
globally serialized it's only serialized on a core.

Simple solution: Let RX use IF1 and TX use IF2 and all is good.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:58 +02:00
Thomas Gleixner
5bb9cbaa62 can: c_can: Fix hardware raminit function
The function is broken in several ways:

    - The function does not wait for the init to complete.
      That can take quite some microseconds.

    - No protection against being called for two chips at the same
      time. SMP is such a new thing, right?

Clear the start and the init done bit unconditionally and wait for both bits to
be clear.

In the enable path set the init bit and wait for the init done bit.

Add proper locking.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:57 +02:00
Thomas Gleixner
9fac1d1ab8 can: c_can: Wait for CONTROL_INIT to be cleared
According to the documentation the CPU must wait for CONTROL_INIT to
be cleared before writing to the baudrate registers.

Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:57 +02:00
Marc Kleine-Budde
130a5171da can: c_can: check return value to users of c_can_set_bittiming()
This patch adds return value checking to all direct and indirect users of
c_can_set_bittiming().

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:56 +02:00
Marc Kleine-Budde
f29b423834 can: c_can: free_c_can_dev(): add missing netif_napi_del()
This patch adds the missing netif_napi_del() to the free_c_can_dev() function.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:56 +02:00
Robert Schwebel
5fb7639dee can: Documentation: fix parameter name "sample-point"
This patch fixes the name of the parameter to configure the sample point used
in iproute2's ip command. The correct writing is "sample-point" not
"sample_point".

Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:55 +02:00
Bjorn Van Tilt
636d0375e7 can: usb_8dev: Fix memory leak in usb_8dev_start_xmit
Fixed a memory leak when an error occurred in the transmit function. In the
error handling the urb wasn't freed before returning. There was also a call to
the usb_unanchor_urb() function but the urb wasn't anchored.

Signed-off-by: Bjorn Van Tilt <bjorn.vantilt@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-04-01 11:54:55 +02:00