Change them over to plain "ETHERNET"
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
* git://git.infradead.org/mtd-2.6: (226 commits)
mtd: tests: annotate as DANGEROUS in Kconfig
mtd: tests: don't use mtd0 as a default
mtd: clean up usage of MTD_DOCPROBE_ADDRESS
jffs2: add compr=lzo and compr=zlib options
jffs2: implement mount option parsing and compression overriding
mtd: nand: initialize ops.mode
mtd: provide an alias for the redboot module name
mtd: m25p80: don't probe device which has status of 'disabled'
mtd: nand_h1900 never worked
mtd: Add DiskOnChip G3 support
mtd: m25p80: add EON flash EN25Q32B into spi flash id table
mtd: mark block device queue as non-rotational
mtd: r852: make r852_pm_ops static
mtd: m25p80: add support for at25df321a spi data flash
mtd: mxc_nand: preset_v1_v2: unlock all NAND flash blocks
mtd: nand: switch `check_pattern()' to standard `memcmp()'
mtd: nand: invalidate cache on unaligned reads
mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set
mtd: nand: wait to set BBT version
mtd: nand: scrub BBT on ECC errors
...
Fix up trivial conflicts:
- arch/arm/mach-at91/board-usb-a9260.c
Merged into board-usb-a926x.c
- drivers/mtd/maps/lantiq-flash.c
add_mtd_partitions -> mtd_device_register vs changed to use
mtd_device_parse_register.
MII Kconfig option is apart of the core networking drivers and
by default NET_CORE is enabled so drivers selecting MII will
have MII enabled as well. It was found using the randconfig
option during testing, MII would be selected but NET_CORE
could be disabled. This caused a dependency error.
Resolved the dependency by selecting NET_CORE when MII is
selected.
Reported-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Recall the recently added prefix requirements:
* "NAND_" for flags in nand.h, used in nand_chip.options
* "NAND_BBT_" for flags in bbm.h, used in nand_chip.bbt_options
or in nand_bbt_descr.options
Thus, I am changing NAND_USE_FLASH_BBT to NAND_BBT_USE_FLASH.
Again, this flag is found in bbm.h and so should NOT be used in the
"nand_chip.options" field.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch works with the following three flags from two headers (nand.h
and bbm.h):
(1) NAND_USE_FLASH_BBT (nand.h)
(2) NAND_USE_FLASH_BBT_NO_OOB (nand.h)
(3) NAND_BBT_NO_OOB (bbm.h)
These flags are all related and interdependent, yet they were in
different headers. Flag (2) is simply the combination of (1) and (3) and
can be eliminated.
This patch accomplishes the following:
* eliminate NAND_USE_FLASH_BBT_NO_OOB (i.e., flag (2))
* move NAND_USE_FLASH_BBT (i.e., flag (1)) to bbm.h
It's important to note that because (1) and (3) are now both found in
bbm.h, they should NOT be used in the "nand_chip.options" field.
I removed a small section from the mtdnand DocBook because it referes to
NAND_USE_FLASH_BBT in nand.h, which has been moved to bbm.h.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert to mtd_device_register() and remove the CONFIG_MTD_PARTITIONS
preprocessor conditionals as partitioning is always available.
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* 'for-linus' of git://www.jni.nu/cris:
Correct auto-restart of syscalls via restartblock
CRISv10: Fix return before mutex_unlock in pcf8563
Drop the CRISv32 version of pcf8563
As MTD_CONCAT support is becoming an integral part of MTD core,
there is no need for it's special treatment. So stop checking for
MTD_CONCAT availability.
Acked by Jesper Nilsson <jesper.nilsson@axis.com> for merging this
via the MTD tree.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
All uses of the big kernel lock in the cris architecture
are for ioctl and open functions of character device drivers,
which can be trivially converted to a per-driver mutex.
Most of these are probably unnecessary, so it may make sense
to audit them and eventually remove the extra mutex introduced
by this patch.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: linux-cris-kernel@axis.com
All these files use the big kernel lock in a trivial
way to serialize their private file operations,
typically resulting from an earlier semi-automatic
pushdown from VFS.
None of these drivers appears to want to lock against
other code, and they all use the BKL as the top-level
lock in their file operations, meaning that there
is no lock-order inversion problem.
Consequently, we can remove the BKL completely,
replacing it with a per-file mutex in every case.
Using a scripted approach means we can avoid
typos.
file=$1
name=$2
if grep -q lock_kernel ${file} ; then
if grep -q 'include.*linux.mutex.h' ${file} ; then
sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
else
sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
fi
sed -i ${file} \
-e "/^#include.*linux.mutex.h/,$ {
1,/^\(static\|int\|long\)/ {
/^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);
} }" \
-e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
-e '/[ ]*cycle_kernel_lock();/d'
else
sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \
-e '/cycle_kernel_lock()/d'
fi
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
From: Frederic Weisbecker <fweisbec@gmail.com>
Pushdown the bkl to the remaining drivers using the
deprecated .ioctl.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
A number of cris specific device drivers still use the
locked ->ioctl operation. Convert them to unlocked_ioctl
with explicit lock_kernel calls.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Commit b26b2d494b ("resource/PCI: align functions now return start
of resource") added lines with missing semicolons.
Add the missing semicolons to the FRV and CRIS arch code.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: linux@dominikbrodowski.net
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
size_t desc_len cannot be less than 0, test before the subtraction.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that we return the new resource start position, there is no
need to update "struct resource" inside the align function.
Therefore, mark the struct resource as const.
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
As suggested by Linus, align functions should return the start
of a resource, not void. An update of "res->start" is no longer
necessary.
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The code didn't test the pointer to the newly allocated
memory, but a parameter sent in as value.
Since the input parameter was most often set, the code
would have used a null pointer if the kmalloc failed.
If the input parameter was not set, the code would
leak the allocated buffer.
http://bugzilla.kernel.org/show_bug.cgi?id=11363
Reported-by: Daniel Marjamäki <danielm77@spray.se>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
arch/cris/arch-v32/drivers/mach-a3/gpio.c:
+spin_lock_irqrestore(&gpio_lock, flags);
arch/cris/arch-v32/drivers/mach-a3/gpio.c:
+spin_lock_irqrestore(&gpio_lock, flags);
should that not be "spin_unlock_irqrestore()"?
The code in question was inside an (most often) undefined ifdef.
Reported-by: "Robert P. J. Day" <rpjday@crashcourse.ca>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Change cris to use the new bcd2bin/bin2bcd functions instead of the
obsolete BCD_TO_BIN/BIN_TO_BCD macros.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Chris Zankel <zankel@tensilica.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://www.jni.nu/cris:
[CRISv10] Clean up compressed/misc.c
[CRISv10] Correct whitespace damage.
[CRIS] Correct definition of subdirs for install_headers.
[CRIS] Correct image makefiles to allow using a separate OBJ-directory.
[CRIS] Build fixes for compressed and rescue images for v10 and v32:
It looks at least odd to apply spin_unlock to a mutex.
cris: compile fixes for 2.6.26-rc5
All of the open() functions which don't need the BKL on their face may
still depend on its acquisition to serialize opens against driver
initialization. So make those functions acquire then release the BKL to be
on the safe side.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This documents the fact that somebody looked at the relevant open()
functions and concluded that, due to their trivial nature, no locking was
needed.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
- Change spin_lock + local_irq_save into spin_lock_irqsave
- Change spin_unlock + local_irq_restore into spin_unlock_irqrestore
- Return ENOTTY if ioctl is not recognized as a cris ioctl.
- Make init functions static.
Changes as suggested by Andrew Morton, plus general cleanup to
ease later consolidation of driver into machine common driver.
- Correct parameter type of gpio_write to const char __user *
- Remove volatile from the arrays of machine dependent registers, use
readl and writel to access them instead.
- Remove useless casts of void.
- Use spin_lock_irqsave for locking.
- Break gpio_write into smaller sub-functions.
- Remove useless breaks after returns.
- Don't perform any change in IO_CFG_WRITE_MODE if values are invalid.
(previously values were set and then set to zero)
- Change cast for copy_to_user to (void __user *)
- Make file_operations gpio_fops static and const.
- Make setget_output static. (However, it's still inline since the CRIS
architecture is still not SMP, which makes the function small enough
to inline)
Clean up issues noticed by Andrew Morton:
- Use a combined struct for allocating the mtd_info and nand_chip structs
instead of using anonymous memory as the example in
Documentation/DocBook/mtdnand.tmpl
- Use kzalloc instead of using kmalloc/memset(0)
- Make crisv32_device_ready static.
- Moved all calls to register_chrdev to a function called by module_init.
- Added mutex locking.
- Added better error handling at start up.
- Added BIN_TO_BCD of the month value before it is saved to the RTC.
- Corrected the month value returned by pcf8563_readreg.
- Cache the voltage low value at driver init so the battery status
information does not get 'accidentally' cleared when setting the RTC time.
- Removed obsolete CONFIG_ETRAX_RTC_READONLY
- Voltage low ioctl():s RTC_VLOW_RD -> RTC_VL_READ, RTC_VLOW_SET -> RTC_VL_CLR
Artem Bityutskiy