linux-toradex.git/drivers/base/regmap/regmap.c, branch v6.17-rc3

regmap: fix potential memory leak of regmap_bus

2025-06-29T21:10:36+00:00

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 
Link: https://patch.msgid.link/20250626172823.18725-1-abdun.nihaal@gmail.com
Signed-off-by: Mark Brown

regmap: regmap_multi_reg_read(): make register list const

2024-12-11T14:24:09+00:00

Mark the list of registers passed into regmap_multi_reg_read() as a
pointer to const. This allows the caller to define the register list
as const data.

This requires making the same change to _regmap_bulk_read(), which is
called by regmap_multi_reg_read().

Signed-off-by: Richard Fitzgerald 
Link: https://patch.msgid.link/20241211133558.884669-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown

regmap: Merge up v6.12-rc2

2024-12-09T12:50:45+00:00

This has fixes for several boards which help my testing a lot.

regmap: place foo / 8 and foo % 8 closer to each other

2024-12-02T00:31:00+00:00

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 
Link: https://patch.msgid.link/20241121105838.4073659-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown

regmap: Use BITS_TO_BYTES()

2024-12-02T00:30:59+00:00

BITS_TO_BYTES() is the existing macro which takes care about full
bytes that may fully hold the given amount of bits. Use it.

Signed-off-by: Andy Shevchenko 
Link: https://patch.msgid.link/20241121105838.4073659-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown

regmap: detach regmap from dev on regmap_exit

2024-12-02T00:29:31+00:00

At the end of __regmap_init(), if dev is not NULL, regmap_attach_dev()
is called, which adds a devres reference to the regmap, to be able to
retrieve a dev's regmap by name using dev_get_regmap().

When calling regmap_exit, the opposite does not happen, and the
reference is kept until the dev is detached.

Add a regmap_detach_dev() function and call it in regmap_exit() to make
sure that the devres reference is not kept.

Cc: stable@vger.kernel.org
Fixes: 72b39f6f2b5a ("regmap: Implement dev_get_regmap()")
Signed-off-by: Cosmin Tanislav 
Rule: add
Link: https://lore.kernel.org/stable/20241128130554.362486-1-demonsingur%40gmail.com
Link: https://patch.msgid.link/20241128131625.363835-1-demonsingur@gmail.com
Signed-off-by: Mark Brown

regmap: Use correct format specifier for logging range errors

2024-12-02T00:29:30+00:00

The register addresses are unsigned ints so we should use %u not %d to
log them.

Signed-off-by: Mark Brown 
Link: https://patch.msgid.link/20241127-regmap-test-high-addr-v1-1-74a48a9e0dc5@kernel.org
Signed-off-by: Mark Brown

regmap: maple: Provide lockdep (sub)class for maple tree's internal lock

2024-10-31T17:24:19+00:00

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]   
[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: [] __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 
Link: https://patch.msgid.link/20241031-regmap-maple-lockdep-fix-v2-1-06a3710f3623@collabora.com
Signed-off-by: Mark Brown

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

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

regmap: Hold the regmap lock when allocating and freeing the cache

2024-08-23T10:03:11+00:00

For the benefit of the maple tree's lockdep checking hold the lock while
creating and exiting the cache.

Signed-off-by: Mark Brown 
Link: https://patch.msgid.link/20240822-b4-regmap-maple-nolock-v1-2-d5e6dbae3396@kernel.org
Signed-off-by: Mark Brown