linux-toradex.git/drivers/mfd/syscon.c, branch v7.0-rc6

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using

    git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook

mfd: syscon: Return -EPROBE_DEFER if the syscon is not found

2025-11-13T14:32:39+00:00

These days we can register syscons with of_syscon_register_regmap() so
when we can't find the syscon that probably means it hasn't been
registered yet.  Return -EPROBE_DEFER so the driver will try probing
again.

Signed-off-by: Dan Carpenter 
Reviewed-by: Arnd Bergmann 
Reviewed-by: Chen-Yu Tsai 
Acked-by: Rob Herring (Arm) 
Link: https://patch.msgid.link/aQdHmrchkmOr34r3@stanley.mountain
Signed-off-by: Lee Jones

Merge tag 'mfd-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd

2025-03-29T21:33:13+00:00

Pull MFD updates from Lee Jones:
"Maxim MAX77705:
- Added core MFD driver.
- Added charger driver.
- Added devicetree bindings for the charger and MFD core.
- Added Haptic controller support via the input subsystem.
- Added LED support.
- Added support to simple-mfd-i2c for fuel gauge and hwmon.

Samsung S2MPU05 (Exynos7870 PMIC):
- Added core MFD support.
- Added Regulator support for 21 LDOs and 5 BUCKs.
- Added devicetree bindings for regulators and the PMIC core.

TI TPS65215 & TPS65214:
- Added support to the existing TPS65219 driver.
- Added devicetree bindings.

STMicroelectronics STM32MP25:
- Added support to the stm32-timers MFD driver.
- Added devicetree bindings.

Congatec Board Controller (CGBC):
- Added HWMON support for internal sensors.
- Added support for the conga-SA8 module.

Microchip LAN969X:
- Enabled the at91-usart MFD driver for this architecture.

MediaTek MT6359:
- Added mfd_cell for mt6359-accdet to allow its driver to probe.

Other misc driver updates:
- AXP20X (AXP717): Added AXP717_TS_PIN_CFG register to writeable regs
for temperature sensor configuration.
- SM501: Switched to using BIT() macro to mitigate potential integer
overflows in GPIO functions.
- ENE KB3930: Added a NULL pointer check for off_gpios during probe
to prevent potential dereference.
- SYSCON: Added a check for invalid resource size to prevent issues
from DT misconfiguration.
- CGBC: Corrected signedness issues in cgbc_session_request
- intel_soc_pmic_chtdc_ti / intel_soc_pmic_crc: Removed unneeded
explicit assignment to REGCACHE_NONE.
- ipaq-micro / tps65010: Switched to using str_enable_disable()
helpers for clarity and potential size reduction.
- upboard-fpga: Removed unnecessary ACPI_PTR() annotation.
- max8997: Removed unused max8997_irq_exit() function, using devm_*
helpers instead.
- lp3943: Dropped unused #include from the header file.
- db8500-prcmu: Removed needless return statements in void APIs.
- qnap-mcu: Replaced commas with semicolons between expressions for
correctness.
- STA2X11: Removed the core MFD driver as the underlying platform
support was removed.
- EZX-PCAP: Removed the unused pcap_adc_sync function.
- PCF50633 (OpenMoko PMIC): Removed the entire driver (core, adc,
gpio, irq) as the underlying s3c24xx platform support was removed.

Devicetree updates:
- Converted fsl,mcu-mpc8349emitx binding to YAML
- Added qcom,msm8937-tcsr compatible
- Added microchip,sama7d65-flexcom compatible
- Added rockchip,rk3528-qos syscon compatible
- Added airoha,en7581-pbus-csr syscon compatible
- Added microchip,sama7d65-ddr3phy syscon compatible
- Added microchip,sama7d65-sfrbu syscon compatible"

* tag 'mfd-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (49 commits)
mfd: cgbc-core: Add support for conga-SA8
dt-bindings: mfd: syscon: Add microchip,sama7d65-sfrbu
dt-bindings: mfd: syscon: Add microchip,sama7d65-ddr3phy
mfd: cgbc: Add support for HWMON
dt-bindings: mfd: syscon: Add the pbus-csr node for Airoha EN7581 SoC
mfd: cgbc-core: Cleanup signedness in cgbc_session_request()
mfd: pcf50633: Remove remaining PCF50633 support
mfd: pcf50633: Remove unused platform IRQ code
mfd: pcF50633-gpio: Remove unused driver
mfd: pcf50633-adc: Remove unused driver
mfd: qnap-mcu: Convert commas to semicolons in qnap_mcu_exec()
mfd: mt6397-core: Add mfd_cell for mt6359-accdet
dt-bindings: mfd: syscon: Add rk3528 QoS register compatible
dt-bindings: mfd: atmel,sama5d2-flexcom: Add microchip,sama7d65-flexcom
mfd: ezx-pcap: Remove unused pcap_adc_sync
mfd: db8500-prcmu: Remove needless return in three void APIs
mfd: Remove STA2x11 core driver
mfd: max77620: Allow building as a module
mfd: ene-kb3930: Fix a potential NULL pointer dereference
dt-bindings: mfd: qcom,tcsr: Add compatible for MSM8937
...

mfd: syscon: Add check for invalid resource size

2025-03-14T08:59:07+00:00

Add a consistency check to avoid assigning an invalid value to
max_register due to a possible DT misconfiguration.

Suggested-by: Mark Langsdorf 
Signed-off-by: Eder Zulian 
Link: https://lore.kernel.org/r/20250212184524.585882-1-ezulian@redhat.com
Signed-off-by: Lee Jones

mfd: syscon: Restore device_node_to_regmap() for non-syscon nodes

2025-02-11T14:53:39+00:00

Commit ba5095ebbc7a ("mfd: syscon: Allow syscon nodes without a
"syscon" compatible") broke drivers which call device_node_to_regmap()
on nodes without a "syscon" compatible. Restore the prior behavior for
device_node_to_regmap().

This also makes using device_node_to_regmap() incompatible with
of_syscon_register_regmap() again, so add kerneldoc for
device_node_to_regmap() and syscon_node_to_regmap() to make it clear
how and when each one should be used.

Fixes: ba5095ebbc7a ("mfd: syscon: Allow syscon nodes without a "syscon" compatible")
Reported-by: Vaishnav Achath 
Signed-off-by: Rob Herring (Arm) 
Reviewed-by: Daniel Golle 
Reviewed-by: AngeloGioacchino Del Regno 
Tested-by: Chen-Yu Tsai 
Tested-by: Nishanth Menon 
Tested-by: Daniel Golle 
Tested-by: Frank Wunderlich 
Tested-by: Dhruva Gole 
Tested-by: Nícolas F. R. A. Prado 
Tested-by: AngeloGioacchino Del Regno 
Link: https://lore.kernel.org/r/20250124191644.2309790-1-robh@kernel.org
Signed-off-by: Lee Jones

mfd: syscon: Allow syscon nodes without a "syscon" compatible

2025-01-09T11:11:54+00:00

of_syscon_register_regmap() was added for nodes which need a custom
regmap setup. It's not really correct for those nodes to claim they are
compatible with "syscon" as the default handling likely doesn't work in
those cases. If device_node_get_regmap() happens to be called first,
then of_syscon_register() will be called and an incorrect regmap will be
created (barring some other error). That may lead to unknown results in
the worst case. In the best case, of_syscon_register_regmap() will fail
with -EEXIST. This problem remains unless these cases drop "syscon" (an
ABI issue) or we exclude them using their specific compatible. ATM,
there is only one user: "google,gs101-pmu"

There are also cases of adding "syscon" compatible to existing nodes
after the fact in order to register the syscon. That presents a
potential DT ABI problem. Instead, if there's a kernel change needing a
syscon for a node, then it should be possible to allow the kernel to
register a syscon without a DT change. That's only possible by using
of_syscon_register_regmap() currently, but in the future we may want to
support a match list for cases which don't need a custom regmap.

With this change, the lookup functions will succeed for any node
registered by of_syscon_register_regmap() regardless of whether the node
compatible contains "syscon".

Signed-off-by: Rob Herring (Arm) 
Tested-by: Will McVicker 
Reviewed-by: Pankaj Dubey 
Reviewed-by: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20241217-syscon-fixes-v2-3-4f56d750541d@kernel.org
Signed-off-by: Lee Jones

mfd: syscon: Remove the platform driver support

2025-01-09T11:11:47+00:00

The platform driver is dead code. It is not used by DT platforms since
commit bdb0066df96e ("mfd: syscon: Decouple syscon interface from
platform devices") which said:

    For non-DT based platforms, this patch keeps syscon platform driver
    structure so that syscon can be probed and such non-DT based drivers
    can use syscon_regmap_lookup_by_pdev API and access regmap handles.
    Once all users of "syscon_regmap_lookup_by_pdev" migrated to DT based,
    we can completely remove platform driver of syscon, and keep only helper
    functions to get regmap handles.

The last user of syscon_regmap_lookup_by_pdevname() was removed in 2018.
syscon_regmap_lookup_by_pdevname() was then removed in 2019, but that
commit failed to remove the rest of the platform driver.

Signed-off-by: Rob Herring (Arm) 
Tested-by: Krzysztof Kozlowski 
Tested-by: Will McVicker 
Acked-by: Liviu Dudau 
Reviewed-by: Pankaj Dubey 
Tested-by: Pankaj Dubey 
Reviewed-by: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20241217-syscon-fixes-v2-2-4f56d750541d@kernel.org
Signed-off-by: Lee Jones

mfd: syscon: Fix race in device_node_get_regmap()

2025-01-09T11:11:36+00:00

It is possible for multiple, simultaneous callers calling
device_node_get_regmap() with the same node to fail to find an entry in
the syscon_list. There is a period of time while the first caller is
calling of_syscon_register() that subsequent callers also fail to find
an entry in the syscon_list and then call of_syscon_register() a second
time.

Fix this by keeping the lock held until after of_syscon_register()
completes and adds the node to syscon_list. Convert the spinlock to a
mutex as many of the functions called in of_syscon_register() such as
kzalloc() and of_clk_get() may sleep.

Fixes: bdb0066df96e ("mfd: syscon: Decouple syscon interface from platform devices")
Signed-off-by: Rob Herring (Arm) 
Reviewed-by: Krzysztof Kozlowski 
Tested-by: Krzysztof Kozlowski 
Tested-by: Will McVicker 
Tested-by: Pankaj Dubey 
Reviewed-by: Pankaj Dubey 
Link: https://lore.kernel.org/r/20241217-syscon-fixes-v2-1-4f56d750541d@kernel.org
Signed-off-by: Lee Jones

mfd: syscon: Use regmap max_register_is_0 as needed

2024-10-16T08:04:09+00:00

syscon has always set the optional max_register configuration of
regmap to ensure the correct checks are in place. However, a recent
commit 0ec74ad3c157 ("regmap: rework ->max_register handling")
introduced explicit configuration in regmap framework for register
maps that is exactly 1 register, when max_register is pointing to a
valid register 0. This commit solved a previous limitation of regmap
framework.

Update syscon driver to consistent in regmap configuration for
all sizes of syscons by using this new capability by setting
max_register_is_0, when the max_register is valid and 0.

Signed-off-by: Nishanth Menon 
Link: https://lore.kernel.org/r/20240903184710.1552067-1-nm@ti.com
Signed-off-by: Lee Jones