commit fea88064445a59584460f7f67d102b6e5fc1ca1d upstream.

Since commit 0ec7731655de ("regmap: Ensure range selector registers
are updated after cache sync") opening pcm512x based soundcards fail
with EINVAL and dmesg shows sync cache and pm_runtime_get errors:

[  228.794676] pcm512x 1-004c: Failed to sync cache: -22
[  228.794740] pcm512x 1-004c: ASoC: error at snd_soc_pcm_component_pm_runtime_get on pcm512x.1-004c: -22

This is caused by the cache check result leaking out into the
regcache_sync return value.

Fix this by making the check local-only, as the comment above the
regcache_read call states a non-zero return value means there's
nothing to do so the return value should not be altered.

Fixes: 0ec7731655de ("regmap: Ensure range selector registers are updated after cache sync")
Cc: stable@vger.kernel.org
Signed-off-by: Matthias Reichl <hias@horus.com>
Link: https://lore.kernel.org/r/20231203222216.96547-1-hias@horus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 0ec7731655de196bc1e4af99e495b38778109d22 ]

When we sync the register cache we do so with the cache bypassed in order
to avoid overhead from writing the synced values back into the cache. If
the regmap has ranges and the selector register for those ranges is in a
register which is cached this has the unfortunate side effect of meaning
that the physical and cached copies of the selector register can be out of
sync after a cache sync. The cache will have whatever the selector was when
the sync started and the hardware will have the selector for the register
that was synced last.

Fix this by rewriting all cached selector registers after every sync,
ensuring that the hardware and cache have the same content. This will
result in extra writes that wouldn't otherwise be needed but is simple
so hopefully robust. We don't read from the hardware since not all
devices have physical read support.

Given that nobody noticed this until now it is likely that we are rarely if
ever hitting this case.

Reported-by: Hector Martin <marcan@marcan.st>
Cc: stable@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231026-regmap-fix-selector-sync-v1-1-633ded82770d@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit fd883d79e4dcd2417c2b80756f22a2ff03b0f6e0 ]

There is no sense in doing a cache sync on REGCACHE_NONE regmaps.
Instead of panicking the kernel due to missing cache_ops, return an error
to client driver.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/20230313071812.13577-1-alexander.stein@ew.tq-group.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Fix the following coccicheck warnings:

./drivers/base/regmap/regcache.c:71:3-18: WARNING: Assignment of
0/1 to bool variable.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Zhong <abaci-bugfix@linux.alibaba.com>
Link: https://lore.kernel.org/r/1611215961-33725-1-git-send-email-abaci-bugfix@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Non-incrementing writes can fail if register + length crosses page
border. However for non-incrementing writes we should not check for page
border crossing. Fix this by passing additional flag to _regmap_raw_write
and passing length to _regmap_select_page basing on the flag.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Fixes: cdf6b11daa77 ("regmap: Add regmap_noinc_write API")
Link: https://lore.kernel.org/r/20200917153405.3139200-2-dmitry.baryshkov@linaro.org
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>

Reported-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

Commit 2cbbb579bcbe3 ("regmap: Add the LZO cache support") added support
for LZO compression in regcache, but there were never any users added
afterwards. Since LZO support itself has its own size, it currently is
rather a deoptimization.

So make it optional by introducing a symbol that can be selected by
drivers wanting to make use of it.

Saves e.g. ~46 kB on MIPS (size of LZO support + regcache LZO code).

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Most of the kernel-doc comments in regmap don't actually generate
correctly. This patch fixes up a few common issues, corrects some typos
and adds some missing argument descriptions.

The most common issues being using a : after the function name which
causes the short description to not render correctly and not separating
the long and short descriptions of the function. There are quite a few
instances of arguments not being described or given the wrong name as
well.

This patch doesn't fixup functions/structures that are currently missing
descriptions.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

In 3245d460 (regmap: cache: Fall back to register by register read for
cache defaults) non-readable registers are skipped when initializing
reg_defaults, but are still included in num_reg_defaults. So there can
be uninitialized entries at the end of reg_defaults, which can cause
problems when the register cache initializes from the full array.

Fixed it by excluding non-readable registers from the count as well.

Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Signed-off-by: Mark Brown <broonie@kernel.org>