kernel.git/drivers/mfd/mfd-core.c, branch linux-6.3.y

mfd: Move from strlcpy with unused retval to strscpy

2022-09-28T15:17:39Z

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

2022-09-28T15:09:50Z

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

mfd: core: Use acpi_dev_for_each_child()

2022-06-27T11:22:06Z

Instead of walking the list of children of an ACPI device directly, use acpi_dev_for_each_child() to carry out an action for all of the given ACPI device's children. This will help to eliminate the children list head from struct acpi_device as it is redundant and it is used in questionable ways in some places (in particular, locking is needed for walking the list pointed to it safely, but it is often missing). Signed-off-by: Rafael J. Wysocki Reviewed-by: Andy Shevchenko Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/2726954.BEx9A2HvPv@kreacher

mfd: core: Add missing of_node_put for loop iteration

2021-11-05T14:40:25Z

Early exits from for_each_child_of_node() should decrement the node reference counter. Reported by Coccinelle: drivers/mfd/mfd-core.c:197:2-24: WARNING: Function "for_each_child_of_node" should have of_node_put() before goto around lines 209. Fixes: c94bb233a9fe ("mfd: Make MFD core code Device Tree and IRQ domain aware") Signed-off-by: Krzysztof Kozlowski Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20210528115126.18370-1-krzysztof.kozlowski@canonical.com

mfd: Remove software node conditionally and locate at right place

2021-06-02T09:50:00Z

Currently the software node is removed in error case and at ->remove() stage unconditionally, that ruins the symmetry. Besides, in some cases, when mfd_add_device() fails, the device_remove_software_node() call may lead to NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 00000000 ... EIP: strlen+0x12/0x20 ... kernfs_name_hash+0x13/0x70 kernfs_find_ns+0x32/0xc0 kernfs_remove_by_name_ns+0x2a/0x90 sysfs_remove_link+0x16/0x30 software_node_notify.cold+0x34/0x6b device_remove_software_node+0x5a/0x90 mfd_add_device.cold+0x30a/0x427 Fix all these by guarding device_remove_software_node() with a conditional and locating it at the right place. Fixes: 42e59982917a ("mfd: core: Add support for software nodes") Signed-off-by: Andy Shevchenko Signed-off-by: Lee Jones

mfd: core: Use acpi_find_child_device() for child devices lookup

2021-04-14T15:06:36Z

Use acpi_find_child_device() for child devices lookup in mfd_acpi_add_device() instead of open coded approach. No functional change intended. While at it, amend a note comment, since usage of _ADR is found on other platforms and tables than Intel Galileo Gen 2, in particular USB wired devices are using it, according to Microsoft specifications for embedded platforms. Signed-off-by: Andy Shevchenko Signed-off-by: Lee Jones

mfd: core: Remove support for dangling device properties

2021-04-14T15:06:14Z

From now on only accepting complete software nodes. Signed-off-by: Heikki Krogerus Signed-off-by: Andy Shevchenko Signed-off-by: Lee Jones

mfd: core: Add support for software nodes

2021-04-14T15:06:07Z

The old device property API is going to be removed and replaced with the newer software node API. This prepares MFD subsystem for the transition. Signed-off-by: Heikki Krogerus Signed-off-by: Andy Shevchenko Signed-off-by: Lee Jones

mfd: mfd-core: Ensure disabled devices are ignored without error

2020-08-28T08:51:41Z

Commit e49aa9a9bd22 ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes") changed the semantics for disabled devices in mfd_add_device(). Instead of silently ignoring a disabled child device, an error was returned. On receipt of the error mfd_add_devices() the precedes to remove *all* child devices and returns an all-failed error to the caller, which will inevitably fail the parent device as well. This patch reverts back to the old semantics and ignores child devices which are disabled in Device Tree. Fixes: e49aa9a9bd22 ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes") Reported-by: Icenowy Zheng Tested-by: Icenowy Zheng Signed-off-by: Lee Jones

mfd: core: Fix double-free in mfd_remove_devices_fn()

2020-08-24T13:23:55Z

The pdev.mfd_cell is released by platform_device_release(), which is invoked by platform_device_unregister(). Hence mfd_remove_devices_fn() shouldn't release the cell variable. The double-free bug is reported KASAN during of MFD driver module removal. Fixes: 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes") Reported-by: Marek Szyprowski Signed-off-by: Dmitry Osipenko Signed-off-by: Lee Jones