kernel/linux.git/drivers/mfd/mfd-core.c, branch v6.18.21

mfd: core: Add locking around 'mfd_of_node_list'

2026-03-04T12:21:12+00:00

[ Upstream commit 20117c92bcf9c11afd64d7481d8f94fdf410726e ] Manipulating a list in the kernel isn't safe without some sort of mutual exclusion. Add a mutex any time we access / modify 'mfd_of_node_list' to prevent possible crashes. Cc: stable@vger.kernel.org Fixes: 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes") Signed-off-by: Douglas Anderson Link: https://patch.msgid.link/20251210113002.1.I6ceaca2cfb7eb25737012b166671f516696be4fd@changeid Signed-off-by: Lee Jones Signed-off-by: Sasha Levin

mfd: core: Increment of_node's refcount before linking it to the platform device

2025-10-01T09:28:37+00:00

When an MFD device is added, a platform_device is allocated. If this device is linked to a DT description, the corresponding OF node is linked to the new platform device but the OF node's refcount isn't incremented. As of_node_put() is called during the platform device release, it leads to a refcount underflow. Call of_node_get() to increment the OF node's refcount when the node is linked to the newly created platform device. Signed-off-by: Bastien Curutchet Link: https://lore.kernel.org/r/20250820-mfd-refcount-v1-1-6dcb5eb41756@bootlin.com Signed-off-by: Lee Jones

mfd: Add missing MODULE_DESCRIPTION() macros

2024-07-04T16:38:40+00:00

On x86, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mfd/arizona.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mfd/pcf50633-gpio.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mfd/timberdale.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mfd/ssbi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mfd/rt4831.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mfd/intel_soc_pmic_bxtwc.o Add the missing invocation of the MODULE_DESCRIPTION() macro to all files which have a MODULE_LICENSE(). This includes mfd-core.c and vexpress-sysreg.c which, although they did not produce a warning with the x86 allmodconfig configuration, may cause this warning with other configurations. Signed-off-by: Jeff Johnson Reviewed-by: Charles Keepax Acked-by: Liviu Dudau Acked-by: Andy Shevchenko # for Intel Broxton PMIC Link: https://lore.kernel.org/r/20240609-md-drivers-mfd-v1-1-47cdd0b394e9@quicinc.com Signed-off-by: Lee Jones

mfd: core: Make use of device_set_node()

2024-07-04T16:08:03+00:00

Use device_set_node() instead of assigning pdev->dev.of_node directly because it also sets the firmware node. Signed-off-by: Andy Shevchenko Reviewed-by: Herve Codina Link: https://lore.kernel.org/r/20240530115147.1112498-1-andriy.shevchenko@linux.intel.com Signed-off-by: Lee Jones

mfd: core: Constify the struct device_type usage

2024-02-23T16:27:13+00:00

Since commit aed65af1cc2f ("drivers: make device_type const"), the driver core can properly handle constant struct device_type. Move the mfd_dev_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman Signed-off-by: Ricardo B. Marliere Link: https://lore.kernel.org/r/20240219-device_cleanup-mfd-v1-1-e4eef5ed2da8@marliere.net Signed-off-by: Lee Jones

mfd: core: Ensure disabled devices are skipped without aborting

2023-11-01T10:02:10+00:00

The loop searching for a matching device based on its compatible string is aborted when a matching disabled device is found. This abort prevents to add devices as soon as one disabled device is found. Continue searching for an other device instead of aborting on the first disabled one fixes the issue. Fixes: 22380b65dc70 ("mfd: mfd-core: Ensure disabled devices are ignored without error") Signed-off-by: Herve Codina Reviewed-by: Christophe Leroy Signed-off-by: Christophe Leroy Link: https://lore.kernel.org/r/528425d6472176bb1d02d79596b51f8c28a551cc.1692376361.git.christophe.leroy@csgroup.eu Signed-off-by: Lee Jones

mfd: core: Use of_property_read_reg() to parse "reg"

2023-06-15T15:22:54+00:00

Use the recently added of_property_read_reg() helper to get the untranslated "reg" address value. Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20230609183159.1766429-1-robh@kernel.org Signed-off-by: Lee Jones

mfd: core: Remove .enable() and .disable() callbacks

2023-04-26T10:40:29+00:00

With commit dd77f5fa97d3 ("mfd: Remove toshiba tmio drivers") the last mfd driver that implements these callbacks is gone and since commit 652719b1003a ("w1: remove ds1wm driver") the last user is gone. The corresponding functions mfd_cell_enable() and mfd_cell_disable() are also unused (since commit 0ca222c81977 ("leds: Remove asic3 driver")). Signed-off-by: Uwe Kleine-König Acked-by: Arnd Bergmann Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20230308091257.2404932-1-u.kleine-koenig@pengutronix.de

mfd: Move from strlcpy with unused retval to strscpy

2022-09-28T15:17:39+00:00

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20220818210030.7012-1-wsa+renesas@sang-engineering.com

mfd: core: Delete corresponding OF node entries from list on MFD removal

2022-09-28T15:09:50+00:00

When we consider MFD which implements hotplug (e.g. USB hotplug driver based on product and vendor IDs) functionality it turns out that its sub-devices are correctly matched with corresponding device tree nodes only at the first time. When physical device reboots or is replugged (and MFD driver is disconnected and probed back again) all sub-devices fails in mfd_add_device() with error 'Failed to locate of_node'. The reason of that behavior is that when any MFD sub-device is created for the first time (and matched with device tree node) it is added to the mfd_of_node_list. It looks like this list is never cleaned even if devices added there are intentionally removed from the system. So when MFD device is replugged and all sub-devices are matched with their device tree nodes again they fail as matched nodes already exist in mfd_of_node_list. In other words current implementation does not support MFD with hotplug feature. This commit extends MFD core for hotplugging support by removing appropriate OF node entry from mfd_of_node_list when corresponding device is removed from the system. Thanks to that when device is added once again it can be matched with its device tree node successfully. Signed-off-by: Michal Oleszczyk Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20220809060336.31892-1-m.oleszczyk@grinn-global.com