Change the 'ret' variable from unsigned int to int to store negative error
codes or zero returned by regmap_field_read() and regmap_read(), and change
'-1' to 'negative errno' in the comments.

Storing the negative error codes in unsigned type, doesn't cause an issue
at runtime but it's ugly as pants. Additionally, assigning negative error
codes to unsigned type may trigger a GCC warning when the -Wsign-conversion
flag is enabled.

No effect on runtime.

Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Message-ID: <20250828150702.193288-1-rongqianfeng@vivo.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

The first thing __regmap_init() do is check if config is non-NULL,
so there is no need to check for this again later.

Fixes: d77e745613680c54 ("regmap: Add bulk read/write callbacks into regmap_config")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/a154d9db0f290dda96b48bd817eb743773e846e1.1755090330.git.geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>

There were already several commits to add module descriptions to regmap
modules.  But this one was still missing:

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

Signed-off-by: Luis Henriques <luis@igalia.com>
Link: https://patch.msgid.link/20250728150829.11890-1-luis@igalia.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull regmap fixes from Mark Brown:
 "These patches fix a lockdep issue Russell King reported with nested
  regmap-irqs (unusual since regmap is generally for devices on slow
  buses so devices don't get nested), plus add a missing mutex free
  which I noticed while implementing a fix for that issue"

* tag 'regmap-fix-v6.17-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: irq: Avoid lockdep warnings with nested regmap-irq chips
  regmap: irq: Free the regmap-irq mutex

While handling interrupts through regmap-irq we use a mutex to protect the
updates we are caching while genirq runs in atomic context. Russell King
reported that while running on the nVidia Jetson Xavier NX this generates
lockdep warnings since that platform has a regmap-irq for the max77686 RTC
which is a child of a max77620 which also uses regmap-irq.

[   46.723127] rtcwake/3984 is trying to acquire lock:
[   46.723235] ffff0000813b2c68 (&d->lock){+.+.}-{4:4}, at: regmap_irq_lock+0x18/0x24
[   46.723452]
               but task is already holding lock:
[   46.723556] ffff00008504dc68 (&d->lock){+.+.}-{4:4}, at: regmap_irq_lock+0x18/0x24

This happens because by default lockdep uses a single lockdep class for all
mutexes initialised from a single mutex_init() call and is unable to tell
that two distinct mutex are being taken and verify that the ordering of
operations is safe. This should be a very rare situation since normally
anything using regmap-irq will be a leaf interrupt controller due to being
on a slow bus like I2C.

We can avoid these warnings by providing the lockdep key for the regmap-irq
explicitly, allocating one for each chip so that lockdep can distinguish
between them.

Thanks to Russell for the report and analysis.

Reported-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20250731-regmap-irq-nesting-v1-2-98b4d1bf20f0@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

We do not currently free the mutex allocated by regmap-irq, do so.

Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20250731-regmap-irq-nesting-v1-1-98b4d1bf20f0@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull regmap updates from Mark Brown:
 "A very quiet release for regmap this time, just two cleanup patches
  and one almost cleanup patch which saves individual MMIO regmaps
  flagging themselves as having fast I/O"

* tag 'regmap-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: Annotate that MMIO implies fast IO
  regmap: get rid of redundant debugfs_file_{get,put}()
  regmap: kunit: Constify regmap_range_cfg array

pointless in ->read()/->write() of file_operations used only via
debugfs_create_file()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://patch.msgid.link/20250702211602.GC3406663@ZenIV
Signed-off-by: Mark Brown <broonie@kernel.org>

When __regmap_init() is called from __regmap_init_i2c() and
__regmap_init_spi() (and their devm versions), the bus argument
obtained from regmap_get_i2c_bus() and regmap_get_spi_bus(), may be
allocated using kmemdup() to support quirks. In those cases, the
bus->free_on_exit field is set to true.

However, inside __regmap_init(), buf is not freed on any error path.
This could lead to a memory leak of regmap_bus when __regmap_init()
fails. Fix that by freeing bus on error path when free_on_exit is set.

Fixes: ea030ca68819 ("regmap-i2c: Set regmap max raw r/w from quirks")
Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>
Link: https://patch.msgid.link/20250626172823.18725-1-abdun.nihaal@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Static 'struct regmap_range_cfg' array is not modified so can be changed
to const for more safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250528194501.567366-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>