kernel/linux.git/drivers/base/regmap/regmap.c, branch v6.18.21

regmap: Synchronize cache for the page selector

2026-04-02T11:23:10+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 Hence the regmap cache initialisation from the HW inherits outdated data in the selector register.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

2026-01-30T09:32:16+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: use int type to store negative error codes

2025-08-28T15:18:40+00:00

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 Message-ID: <20250828150702.193288-1-rongqianfeng@vivo.com> Signed-off-by: Mark Brown

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

2025-08-13T13:19:25+00:00

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

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