linux-stable.git/drivers/base/regmap/regmap.c, branch v6.6.78

regmap: Use correct format specifier for logging range errors

2025-01-02T09:32:05+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

2024-12-14T19:00:01+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

2024-12-14T18:59:57+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

regmap: Add regmap_read_bypassed()

2024-05-17T10:01:59+00:00

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

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 
Fixes: 8a731fd37f8b ("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 
Signed-off-by: Sasha Levin

regmap: prevent noinc writes from clobbering cache

2023-11-20T10:59:33+00:00

[ Upstream commit 984a4afdc87a1fc226fd657b1cd8255c13d3fc1a ]

Currently, noinc writes are cached as if they were standard incrementing
writes, overwriting unrelated register values in the cache. Instead, we
want to cache the last value written to the register, as is done in the
accelerated noinc handler (regmap_noinc_readwrite).

Fixes: cdf6b11daa77 ("regmap: Add regmap_noinc_write API")
Signed-off-by: Ben Wolsieffer 
Link: https://lore.kernel.org/r/20231101142926.2722603-2-ben.wolsieffer@hefring.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regmap: fix NULL deref on lookup

2023-10-09T12:13:53+00:00

Not all regmaps have a name so make sure to check for that to avoid
dereferencing a NULL pointer when dev_get_regmap() is used to lookup a
named regmap.

Fixes: e84861fec32d ("regmap: dev_get_regmap_match(): fix string comparison")
Cc: stable@vger.kernel.org      # 5.8
Cc: Marc Kleine-Budde 
Signed-off-by: Johan Hovold 
Link: https://lore.kernel.org/r/20231006082104.16707-1-johan+linaro@kernel.org
Signed-off-by: Mark Brown

regmap: Merge up fixes from mainline

2023-07-23T22:34:06+00:00

There's several things here that will really help my CI.

regmap: Remove dynamic allocation warnings for rbtree and maple

2023-07-21T16:36:09+00:00

Thanks to Dan and Guenter's very prompt updates of the rbtree and maple
caches to support GPF_ATOMIC allocations and since the update shook out
a bunch of users at least some of whom have been suitably careful about
ensuring that the cache is prepoulated so there are no dynamic
allocations after init let's revert the warnings.

Signed-off-by: Mark Brown 
Link: https://lore.kernel.org/r/20230721-regmap-enable-kmalloc-v1-1-f78287e794d3@kernel.org

regmap: Reject fast_io regmap configurations with RBTREE and MAPLE caches

2023-07-20T12:57:05+00:00

REGCACHE_RBTREE and REGCACHE_MAPLE dynamically allocate memory for regmap
operations. This is incompatible with spinlock based locking which is used
for fast_io operations. Reject affected configurations.

Signed-off-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20230720032848.1306349-2-linux@roeck-us.net
Signed-off-by: Mark Brown

regmap: Drop initial version of maximum transfer length fixes

2023-07-17T05:15:14+00:00

When problems were noticed with the register address not being taken
into account when limiting raw transfers with I2C devices we fixed this
in the core.  Unfortunately it has subsequently been realised that a lot
of buses were relying on the prior behaviour, partly due to unclear
documentation not making it obvious what was intended in the core.  This
is all more involved to fix than is sensible for a fix commit so let's
just drop the original fixes, a separate commit will fix the originally
observed problem in an I2C specific way

Fixes: 3981514180c9 ("regmap: Account for register length when chunking")
Fixes: c8e796895e23 ("regmap: spi-avmm: Fix regmap_bus max_raw_write")
Signed-off-by: Mark Brown 
Reviewed-by: Xu Yilun 
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20230712-regmap-max-transfer-v1-1-80e2aed22e83@kernel.org
Signed-off-by: Mark Brown