Prevent _regmap_update_bits() from accessing hardware when the register
map is in cache-only mode.
Unlike regmap_raw_read() and _regmap_read(), the volatile
_regmap_update_bits() fast path bypasses the cache_only check. This can
result in unexpected hardware accesses while the device is suspended.
Return -EBUSY to ensure behavior is consistent with other cache-only
access paths.
Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Link: https://patch.msgid.link/20260528053204.46783-1-phucduc.bui@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The resource-managed devm_regmap_init() can be a bit simpler by using
devm_add_action_or_reset() instead of devres_alloc(). This allows to
drop the less-obvious pointer to pointer (struct regmap **ptr) and make
devm_regmap_release() interface simpler.
Code is functionally equivalent with minor difference: devres_alloc()
will happen now after successful resource init (__regmap_init()).
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20260305201349.32734-2-krzysztof.kozlowski@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Commit e062bdfdd6 ("regmap: warn users about uninitialized flat cache")
warns when REGCACHE_FLAT is used without full defaults. This causes
false positives on hardware where many registers reset to zero but are
not listed in reg_defaults, forcing drivers to maintain large tables
just to silence the warning.
Add a reg_default_cb() hook so drivers can supply defaults for registers
not present in reg_defaults when populating REGCACHE_FLAT. This keeps
the warning quiet for known zero-reset registers without bloating
tables. Provide a generic regmap_default_zero_cb() helper for drivers
that need zero defaults.
The hook is only used for REGCACHE_FLAT; the core does not
check readable/writeable access, so drivers must provide readable_reg/
writeable_reg callbacks and handle holes in the register map.
Signed-off-by: Sheetal <sheetal@nvidia.com>
Link: https://patch.msgid.link/20260123095346.1258556-3-sheetal@nvidia.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Previously, the address of the shared member '&map->spinlock_flags' was
passed directly to 'hwspin_lock_timeout_irqsave'. This creates a race
condition where multiple contexts contending for the lock could overwrite
the shared flags variable, potentially corrupting the state for the
current lock owner.
Fix this by using a local stack variable 'flags' to store the IRQ state
temporarily.
Fixes: 8698b93647 ("regmap: Add hardware spinlock support")
Signed-off-by: Cheng-Yu Lee <cylee12@realtek.com>
Co-developed-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Link: https://patch.msgid.link/20260109032633.8732-1-eleanor.lin@realtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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>
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: ea030ca688 ("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>
On x86 the compiler (gcc (Debian 14.2.0-8) 14.2.0) may generate
a better code if it sees division and modulo goes together.
Function old new delta
__regmap_init 3740 3732 -8
Total: Before=31159, After=31151, chg -0.03%
clang (Debian clang version 18.1.8) on x86_64 still shows better code
Function old new delta
__regmap_init 3582 3579 -3
Total: Before=39854, After=39851, chg -0.01%
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20241121105838.4073659-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In some cases when using the maple tree register cache, the lockdep
validator might complain about invalid deadlocks:
[7.131886] Possible interrupt unsafe locking scenario:
[7.131890] CPU0 CPU1
[7.131893] ---- ----
[7.131896] lock(&mt->ma_lock);
[7.131904] local_irq_disable();
[7.131907] lock(rockchip_drm_vop2:3114:(&vop2_regmap_config)->lock);
[7.131916] lock(&mt->ma_lock);
[7.131925] <Interrupt>
[7.131928] lock(rockchip_drm_vop2:3114:(&vop2_regmap_config)->lock);
[7.131936]
*** DEADLOCK ***
[7.131939] no locks held by swapper/0/0.
[7.131944]
the shortest dependencies between 2nd lock and 1st lock:
[7.131950] -> (&mt->ma_lock){+.+.}-{2:2} {
[7.131966] HARDIRQ-ON-W at:
[7.131973] lock_acquire+0x200/0x330
[7.131986] _raw_spin_lock+0x50/0x70
[7.131998] regcache_maple_write+0x68/0xe0
[7.132010] regcache_write+0x6c/0x90
[7.132019] _regmap_read+0x19c/0x1d0
[7.132029] _regmap_update_bits+0xc0/0x148
[7.132038] regmap_update_bits_base+0x6c/0xa8
[7.132048] rk8xx_probe+0x22c/0x3d8
[7.132057] rk8xx_spi_probe+0x74/0x88
[7.132065] spi_probe+0xa8/0xe0
[...]
[7.132675] }
[7.132678] ... key at: [<ffff800082943c20>] __key.0+0x0/0x10
[7.132691] ... acquired at:
[7.132695] _raw_spin_lock+0x50/0x70
[7.132704] regcache_maple_write+0x68/0xe0
[7.132714] regcache_write+0x6c/0x90
[7.132724] _regmap_read+0x19c/0x1d0
[7.132732] _regmap_update_bits+0xc0/0x148
[7.132741] regmap_field_update_bits_base+0x74/0xb8
[7.132751] vop2_plane_atomic_update+0x480/0x14d8 [rockchipdrm]
[7.132820] drm_atomic_helper_commit_planes+0x1a0/0x320 [drm_kms_helper]
[...]
[7.135112] -> (rockchip_drm_vop2:3114:(&vop2_regmap_config)->lock){-...}-{2:2} {
[7.135130] IN-HARDIRQ-W at:
[7.135136] lock_acquire+0x200/0x330
[7.135147] _raw_spin_lock_irqsave+0x6c/0x98
[7.135157] regmap_lock_spinlock+0x20/0x40
[7.135166] regmap_read+0x44/0x90
[7.135175] vop2_isr+0x90/0x290 [rockchipdrm]
[7.135225] __handle_irq_event_percpu+0x124/0x2d0
In the example above, the validator seems to get the scope of
dependencies wrong, since the regmap instance used in rk8xx-spi driver
has nothing to do with the instance from vop2.
Improve validation by sharing the regmap's lockdep class with the maple
tree's internal lock, while also providing a subclass for the latter.
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://patch.msgid.link/20241031-regmap-maple-lockdep-fix-v2-1-06a3710f3623@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
Merge series from Guenter Roeck <linux@roeck-us.net>:
regmap_multi_reg_read() is similar to regmap_bilk_read() but reads from
an array of non-sequential registers. It is helpful if multiple non-
sequential registers need to be read in a single operation which would
otherwise have to be mutex protected.
The name of the new function was chosen to match the existing function
regmap_multi_reg_write().
Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.
A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.
For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When regmap consists of single register, 'regmap' subsystem is unable to
understand whether ->max_register is set or not, because in both cases it
is equal to zero. It leads to that the logic based on value of
->max_register doesn't work. For example using of REGCACHE_FLAT fails.
This patch introduces an extra parameter to regmap config, indicating
that zero value in ->max_register is authentic.
Signed-off-by: Jan Dakinevich <jan.dakinevich@salutedevices.com>
Link: https://lore.kernel.org/r/20240126200836.1829995-1-jan.dakinevich@salutedevices.com
Signed-off-by: Mark Brown <broonie@kernel.org>
bui duc phucandMark Brown
Andy ShevchenkoandMark Brown
Krzysztof KozlowskiandMark Brown
Linus Torvalds
Kees Cook
SheetalandMark Brown
Cheng-Yu LeeandMark Brown
Qianfeng RongandMark Brown
Geert UytterhoevenandMark Brown
Abdun NihaalandMark Brown
Richard FitzgeraldandMark Brown
Cosmin TanislavandMark Brown
Cristian CiocalteaandMark Brown
Al Viro
Guenter RoeckandMark Brown
Jan DakinevichandMark Brown
Hugo VilleneuveandMark Brown