linux.git/drivers/base/regmap/regmap.c, branch v6.12.80

regmap: Synchronize cache for the page selector

2026-04-02T11:09:37+00:00

[ Upstream commit 09e70e4f119ff650d24c96161fd2f62ac7e424b0 ]

If the selector register is represented in each page, its value
according to the debugfs is stale because it gets synchronized
only after the real page switch happens. Hence the regmap cache
initialisation from the HW inherits outdated data in the selector
register.

Synchronize cache for the page selector just in time.

Before (offset followed by hexdump, the first byte is selector):

    // Real registers
    18: 05 ff 00 00 ff 0f 00 00 f0 00 00 00
    ...
    // Virtual (per port)
    40: 05 ff 00 00 e0 e0 00 00 00 00 00 1f
    50: 00 ff 00 00 e0 e0 00 00 00 00 00 1f
    60: 01 ff 00 00 ff ff 00 00 00 00 00 00
    70: 02 ff 00 00 cf f3 00 00 00 00 00 0c
    80: 03 ff 00 00 00 00 00 00 00 00 00 ff
    90: 04 ff 00 00 ff 0f 00 00 f0 00 00 00

After:

    // Real registers
    18: 05 ff 00 00 ff 0f 00 00 f0 00 00 00
    ...
    // Virtual (per port)
    40: 00 ff 00 00 e0 e0 00 00 00 00 00 1f
    50: 01 ff 00 00 e0 e0 00 00 00 00 00 1f
    60: 02 ff 00 00 ff ff 00 00 00 00 00 00
    70: 03 ff 00 00 cf f3 00 00 00 00 00 0c
    80: 04 ff 00 00 00 00 00 00 00 00 00 ff
    90: 05 ff 00 00 ff 0f 00 00 f0 00 00 00

Fixes: 6863ca622759 ("regmap: Add support for register indirect addressing.")
Signed-off-by: Andy Shevchenko 
Link: https://patch.msgid.link/20260302184753.2693803-1-andriy.shevchenko@linux.intel.com
Tested-by: Marek Szyprowski 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regmap: Fix race condition in hwspinlock irqsave routine

2026-01-30T09:28:41+00:00

[ Upstream commit 4b58aac989c1e3fafb1c68a733811859df388250 ]

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: 8698b9364710 ("regmap: Add hardware spinlock support")
Signed-off-by: Cheng-Yu Lee 
Co-developed-by: Yu-Chun Lin 
Signed-off-by: Yu-Chun Lin 
Link: https://patch.msgid.link/20260109032633.8732-1-eleanor.lin@realtek.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regmap: Remove superfluous check for !config in __regmap_init()

2025-10-15T09:59:55+00:00

[ Upstream commit 5c36b86d2bf68fbcad16169983ef7ee8c537db59 ]

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 
Link: https://patch.msgid.link/a154d9db0f290dda96b48bd817eb743773e846e1.1755090330.git.geert+renesas@glider.be
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regmap: fix potential memory leak of regmap_bus

2025-08-01T08:48:40+00:00

[ Upstream commit c871c199accb39d0f4cb941ad0dccabfc21e9214 ]

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 
Signed-off-by: Sasha Levin

regmap: Use correct format specifier for logging range errors

2025-01-02T09:34:18+00:00

[ Upstream commit 3f1aa0c533d9dd8a835caf9a6824449c463ee7e2 ]

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 
Signed-off-by: Sasha Levin

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

2024-12-14T19:03:40+00:00

[ Upstream commit 1ed9b927e7dd8b8cff13052efe212a8ff72ec51d ]

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 
Signed-off-by: Sasha Levin

regmap: detach regmap from dev on regmap_exit

2024-12-14T19:03:31+00:00

commit 3061e170381af96d1e66799d34264e6414d428a7 upstream.

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 
Signed-off-by: Greg Kroah-Hartman

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

regmap: Implement regmap_multi_reg_read()

2024-07-10T22:05:45+00:00

Merge series from Guenter Roeck :

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().