kernel/linux.git/drivers/base/regmap/regmap.c, branch v6.6.132

regmap: Synchronize cache for the page selector

2026-04-02T11:07:21+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 Hence the regmap cache initialisation from the HW inherits outdated data in the selector register.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

2026-01-30T09:27:35+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()

2025-10-15T09:57:49+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

2025-08-01T08:47:28+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

2025-01-02T09:32:05+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