regmap_debugfs_get_dump_start should return the offset of the register
it should start reading from, However in the current code at one point
the code does not return correct register offset.
With this patch all the returns from this function takes reg_stride in
to consideration to return correct offset.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
A register write to hardware is reasonably unlikely to cause locking
dependency issues, the reason we're tainting is that unexpected changes
in the hardware configuration may confuse drivers.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This file lists the register ranges in the register map. The condition
to split the range is based on whether the block is readable or not.
Ensure that we lock the `debugfs_off_cache' list whenever we access
and modify the list. There is a possible race otherwise between the
read() operations of the `registers' file and the `range' file.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
We don't need to use any of the file position information
to calculate the base and max register of each block. Just
use the counter directly.
Set `i = base' at the top to avoid GCC flow analysis bugs. The
value of `i' can never be undefined or 0 in the if (c) { ... }.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Pull module update from Rusty Russell:
"The sweeping change is to make add_taint() explicitly indicate whether
to disable lockdep, but it's a mechanical change."
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
MODSIGN: Add option to not sign modules during modules_install
MODSIGN: Add -s <signature> option to sign-file
MODSIGN: Specify the hash algorithm on sign-file command line
MODSIGN: Simplify Makefile with a Kconfig helper
module: clean up load_module a little more.
modpost: Ignore ARC specific non-alloc sections
module: constify within_module_*
taint: add explicit flag to show whether lock dep is still OK.
module: printk message when module signature fail taints kernel.
In preparation to support the regmap debugfs ranges functionality
factor this code out to a separate function. We'll need to ensure
that the value has been correctly calculated from two separate places
in the code.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Optimize this so that we can better guess where to start scanning
from. We know the length of the register field format, therefore
given the file pointer position align to the nearest register
field and scan from there onwards. We round down in this calculation
and we let the rest of the code figure out where to start scanning
from.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
We are keeping track of the maximum register as well, this will make
things easier for us in sharing this code with the code implementing
the register ranges functionality. It also simplifies a bit the
calculations when looking for the relevant block:offset from within
the cache.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
At the moment, if the length of the register field format is
N bytes, we can only get anything meaningful back to userspace
by providing a buffer that is N + 2 bytes large. Fix this
so we that we only need to provide a buffer of N bytes.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Gcc warns about the case where regmap_read_debugfs tries to walk an
empty map->debugfs_off_cache list, which would results in uninitialized
variable getting returned, if we hadn't checked the same condition
just before that.
After an originally suggested inferior patch from Arnd Bergmann,
this is the solution that Russell King came up with, sidestepping
the problem by merging the error case for an empty list with the
normal path.
Without this patch, building mxs_defconfig results in:
drivers/base/regmap/regmap-debugfs.c: In function 'regmap_read_debugfs':
drivers/base/regmap/regmap-debugfs.c:147:9: : warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
Reported-by: Vincent Stehle <v-stehle@ti.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Fix up all callers as they were before, with make one change: an
unsigned module taints the kernel, but doesn't turn off lockdep.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't want to bomb out early if we failed to get the cache any more,
just soldier on instead and we won't get confused and always return the
first block.
Reported-by: Philipp Zabel <p.zabel@pengutronix.de
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Rather than trying to soldier on with a partially allocated cache just
throw the cache away and pretend we don't have one in case we can get a
full cache next time around.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Return the start of the last block we tried to read rather than a position,
and also make sure we update the byte position while we're at it. Without
this reads that go into nonexistant areas get confused.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Avoid doing a linear scan of the entire register map for each read() of
the debugfs register dump by recording the offsets where valid registers
exist when we first read the registers file. This assumes the set of
valid registers never changes, if this is not the case invalidation of
the cache will be required.
This could be further improved for large blocks of contiguous registers
by calculating the register we will read from within the block - currently
we do a linear scan of the block. An rbtree may also be worthwhile.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
In preparation for doing things a bit more quickly than a linear scan
factor out the initial seek from the debugfs register dump.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
If count is less than the size of a register then we may hit integer
wraparound when trying to move backwards to check if we're still in
the buffer. Instead move the position forwards to check if it's still
in the buffer, we are unlikely to be able to allocate a buffer
sufficiently big to overflow here.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org
