Pull regmap fixes from Mark Brown:
"A couple of substantial fixes here, one from Doug which fixes the
debugfs code for MMIO regmaps (fortunately not the common case) and
one from Marc fixing lookups of multiple regmaps for the same device
(a very unusual case).
There's also a fix for Kconfig to ensure we enable SoundWire properly"
* tag 'regmap-fix-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: debugfs: Don't sleep while atomic for fast_io regmaps
regmap: add missing dependency on SoundWire
regmap: dev_get_regmap_match(): fix string comparison
If a regmap has "fast_io" set then its lock function uses a spinlock.
That doesn't work so well with the functions:
* regmap_cache_only_write_file()
* regmap_cache_bypass_write_file()
Both of the above functions have the pattern:
1. Lock the regmap.
2. Call:
debugfs_write_file_bool()
copy_from_user()
__might_fault()
__might_sleep()
Let's reorder things a bit so that we do all of our sleepable
functions before we grab the lock.
Fixes: d3dc5430d6 ("regmap: debugfs: Allow writes to cache state settings")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200715164611.1.I35b3533e8a80efde0cec1cc70f71e1e74b2fa0da@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>
When executing the following command, we met kernel dump.
dmesg -c > /dev/null; cd /sys;
for i in `ls /sys/kernel/debug/regmap/* -d`; do
echo "Checking regmap in $i";
cat $i/registers;
done && grep -ri "0x02d0" *;
It is because the count value is too big, and kmalloc fails. So add an
upper bound check to allow max size `PAGE_SIZE << (MAX_ORDER - 1)`.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/1584064687-12964-1-git-send-email-peng.fan@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
The debugfs core will warn if a file or directory can not be created, so
there's no need to duplicate the warning, nor really do anything else.
Cc: Mark Brown <broonie@kernel.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190731132923.GA13829@kroah.com
Signed-off-by: Mark Brown <broonie@kernel.org>
There were a few files in the regmap code that did not have SPDX
identifiers on them, so fix that up. At the same time, remove the "free
form" text that specified the license of the file, as that is impossible
for any tool to properly parse.
Also, as Mark loves // comment markers, convert all of the headers to be
the same to make things look consistent :)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently when debugfs_create_dir() fails we receive a warning message
that provides no indication as to what was the directory entry that
failed to be created.
Improve the warning message by printing the directory name that failed
in order to help debugging.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Free map->debugfs_name when debugfs_create_dir() failed to avoid memory
leak.
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When allocating dummy names we need to store a pointer to the string we
allocate so that we don't leak it on free.
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit 9b947a13e7 ("regmap: use debugfs even when no device")
allows the usage of regmap debugfs even when there is no device
associated, which causes several warnings like this:
(NULL device *): Failed to create debugfs directory
This happens when the debugfs file name is 'dummy'.
The first dummy debugfs creation works fine, but subsequent creations
fail as they have all the same name.
Disambiguate the 'dummy' debugfs file name by adding a suffix entry,
so that the names become dummy0, dummy1, dummy2, etc.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This fixes a possible NULL pointer dereference oops in
regmap_name_read_file() when the regmap does not have a device
associated with it. For example syscon regmaps retrieved with
syscon_regmap_lookup_by_compatible() don't have a device.
Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This is a follow-up to commit a5ba91c380 ("regmap: debugfs: emit a
debug message when locking is disabled"). I figured that a user may
see this message, grep the code, come to this place and he still won't
know why we actually disabled debugfs.
Add a comment explaining the reason.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Mark Brown <broonie@kernel.org>
We currently silently omit creating the debugfs entries when regmap
locking is disabled. Users may not be aware of the reason for which
regmap files don't show up in debugfs. Add a dev_dbg() message
explaining that.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Mark Brown <broonie@kernel.org>
The recently added support for disabling the regmap internal locking left
debugfs enabled for devices with the locking disabled. This is a problem
since debugfs allows userspace to do things like initiate reads from the
hardware which will use the scratch buffers protected by the regmap locking
so could cause data corruption.
For safety address this by just disabling debugfs for these devices. That
is overly conservative since some of the debugfs files just read internal
data structures but it's much simpler to implmement and less likely to
lead to problems with tooling that works with debugfs.
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for dumping write only device registers in debugfs. This is
useful for audio codecs that have write only registers (like WM8731).
The logic that decides if a value can be printed is moved to
regmap_printable() function to allow for easier future updates.
Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Unlike the registers file we don't have any substantial performance
concerns rendering the entire file (it involves no device accesses) so
just use seq_printf() to simplify the code.
Signed-off-by: Mark Brown <broonie@kernel.org>
By printing the newline character to entry, we can avoid accounting
for it manually in several places.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since we know the length of entry and that there's room enough in the
output buffer, using memcpy instead of snprintf is simpler and
cheaper.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Calling strlen() no less than three times on entry is silly. Since
we're formatting into a buffer with plenty of room, there's no chance
of truncation, so snprintf() has actually returned the value we want,
meaning we don't even have to call strlen once.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now we no longer use the scratch buffer for register length calculation
there is no need for callers to supply one.
Signed-off-by: Mark Brown <broonie@kernel.org>
The in kernel snprintf() will conveniently return the actual length of
the printed string even if not given an output beffer at all so just do
that rather than relying on the user to pass in a suitable buffer,
ensuring that we don't need to worry if the buffer was truncated due to
the size of the buffer passed in.
Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
If a read is attempted which is smaller than the line length then we may
underflow the subtraction we're doing with the unsigned size_t type so
move some of the calculation to be additions on the right hand side
instead in order to avoid this.
Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
