Currently, when an adapter defines a max_write_len quirk,
the data will be chunked into data sizes equal to the
max_write_len quirk value.  But the payload will be increased by
the size of the register address before transmission.  The
resulting value always ends up larger than the limit set
by the quirk.

Avoid this error by setting regmap's max_write to the quirk's
max_write_len minus the number of bytes for the register and
padding.  This allows the chunking to work correctly for this
limited case without impacting other use-cases.

Signed-off-by: Jim Wylder <jwylder@google.com>
Link: https://msgid.link/r/20240523211437.2839942-1-jwylder@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull regmap fix from Mark Brown:
 "Guenter ran with memory sanitisers and found an issue in the new KUnit
  tests that Richard added where an assumption in older test code was
  exposed, this was fixed quickly by Richard"

* tag 'regmap-fix-v6.10-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: kunit: Fix array overflow in stride() test

With the rework of how the __string() handles dynamic strings where it
saves off the source string in field in the helper structure[1], the
assignment of that value to the trace event field is stored in the helper
value and does not need to be passed in again.

This means that with:

  __string(field, mystring)

Which use to be assigned with __assign_str(field, mystring), no longer
needs the second parameter and it is unused. With this, __assign_str()
will now only get a single parameter.

There's over 700 users of __assign_str() and because coccinelle does not
handle the TRACE_EVENT() macro I ended up using the following sed script:

  git grep -l __assign_str | while read a ; do
      sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file;
      mv /tmp/test-file $a;
  done

I then searched for __assign_str() that did not end with ';' as those
were multi line assignments that the sed script above would fail to catch.

Note, the same updates will need to be done for:

  __assign_str_len()
  __assign_rel_str()
  __assign_rel_str_len()

I tested this with both an allmodconfig and an allyesconfig (build only for both).

[1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/

Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts.
Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for
Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>	# xfs
Tested-by: Guenter Roeck <linux@roeck-us.net>

Force the max_register of the test regmap to be one register longer
than the number of test registers, to prevent an array overflow in
the test loop.

The test defines num_reg_defaults = 6. With 6 registers and
stride == 2 the valid register addresses would be 0, 2, 4, 6, 8, 10.
However the loop checks attempting to access the odd address, so on
the final register it accesses address 11, and it writes entry [11]
of the read/written arrays.

Originally this worked because the max_register of the regmap was
hardcoded to be BLOCK_TEST_SIZE (== 12).

commit 710915743d53 ("regmap: kunit: Run sparse cache tests at non-zero
register addresses")
introduced the ability to start the test address range from any address,
which means adjusting the max_register. If max_register was not forced,
it was calculated either from num_reg_defaults or BLOCK_TEST_SIZE. This
correctly calculated that with num_reg_defaults == 6 and stride == 2 the
final valid address is 10. So the read/written arrays are allocated to
contain entries [0..10]. When stride attempted to access [11] it was
overflowing the array.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 710915743d53 ("regmap: kunit: Run sparse cache tests at non-zero register addresses")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://msgid.link/r/20240517144703.1200995-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

The kunit_device_register() function returns error pointers, not NULL.
Passing an error pointer to get_device() will lead to an Oops.  Also
get_device() returns the same device you passed to it.  Fix it!  ;)

Fixes: 7b7982f14315 ("regmap: kunit: Create a struct device for the regmap")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/b32e80cf-b385-40cd-b8ec-77ec73e07530@moroto.mountain
Signed-off-by: Mark Brown <broonie@kernel.org>

The modpost script is not happy

  WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/base/regmap/regmap-spi.o

because there is a missing module description.

Add it to the module.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://msgid.link/r/20240410202912.1659275-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

'Regmap' should be spelled as 'regmap'. Update that.

Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://msgid.link/r/20240410202912.1659275-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Merge series from Richard Fitzgerald <rf@opensource.cirrus.com>:

This series adds some more test cases, mainly for testing:

commit eaa03486d932 ("regmap: maple: Fix uninitialized symbol 'ret' warnings")
commit 00bb549d7d63 ("regmap: maple: Fix cache corruption in regcache_maple_drop()")

And the pending patch ("regmap: Add regmap_read_bypassed()")

There are also a few small improvements to the KUnit implementation.

This adds test cases to prove that regmap_read_bypassed() reads
the hardware value while the regmap is in cache-only.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://msgid.link/r/20240408144600.230848-12-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Add a test case for dropping only some cache blocks and leaving others
unchanged.

The regmap is divided into 8 register ranges, and only 4 of these are
written with values. This creates 4 non-contiguous ranges of registers
with cached values.

One whole range is then dropped, and part of another range. A cache
sync is then performed to check that the correct registers were written,
and the correct values were written to these registers.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://msgid.link/r/20240408144600.230848-11-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>