linux-toradex.git/include/linux/device.h, branch v6.4-rc1

driver core: device.h: remove extern from function prototypes

2023-03-24T14:35:31+00:00

The kernel coding style does not require 'extern' in function prototypes
in .h files, so remove them from include/linux/device.h as they are not
needed.

Acked-by: Rafael J. Wysocki 
Link: https://lore.kernel.org/r/20230324122711.2664537-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

driver core: device.h: make struct bus_type a const *

2023-03-23T12:21:58+00:00

Now that all users who accessed the bus_type structure in struct device
are properly using it as a const *, mark it as such so that no one can
modify it going forward anymore.

Cc: "Rafael J. Wysocki" 
Link: https://lore.kernel.org/r/20230313182918.1312597-35-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

driver core: device: make device_create() take a const struct class

2023-03-17T14:16:50+00:00

The functions device_create() and device_create_with_groups() do not
modify the struct class passed into it, so enforce this by changing the
function parameters to be struct const class.

Cc: "Rafael J. Wysocki" 
Link: https://lore.kernel.org/r/20230313181843.1207845-12-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

driver core: device: mark struct class in struct device as constant

2023-03-17T14:16:48+00:00

The pointer to a struct class in a struct device should never be used to
change anything in that class.  So mark it as constant to enforce this
requirement.

This requires a few minor changes to some internal driver core functions
to enforce the const * being used here now.

Cc: "Rafael J. Wysocki" 
Link: https://lore.kernel.org/r/20230313181843.1207845-11-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

driver core: device: make device_destroy() take a const class *

2023-03-17T14:16:43+00:00

device_destroy() does not modify the struct class passed into it, so
mark it as const to enforce this rule.

Cc: "Rafael J. Wysocki" 
Link: https://lore.kernel.org/r/20230313181843.1207845-9-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

devres: Pass unique name of the resource to devm_add_action_or_reset()

2023-03-17T14:09:59+00:00

All the same as it's done in the commit e32c80bbd2f9 ("devres:
Pass unique name of the resource to devm_add_action()") applies
to the devm_add_action_or_reset(), which this change makes real.
This helps with debug resource management.

Reported-and-tested-by: Mirsad Goran Todorovac 
Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20230313113100.59643-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

devres: Pass unique name of the resource to devm_add_action()

2023-03-10T08:06:22+00:00

Pass the unique name of the resource to devm_add_action(),
so it will be easier to debug managed resources.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20230224200745.17324-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

driver core: remove CONFIG_SYSFS_DEPRECATED and CONFIG_SYSFS_DEPRECATED_V2

2023-03-06T06:46:23+00:00

CONFIG_SYSFS_DEPRECATED was added in commit 88a22c985e35
("CONFIG_SYSFS_DEPRECATED") in 2006 to allow systems with older versions
of some tools (i.e. Fedora 3's version of udev) to boot properly.  Four
years later, in 2010, the option was attempted to be removed as most of
userspace should have been fixed up properly by then, but some kernel
developers clung to those old systems and refused to update, so we added
CONFIG_SYSFS_DEPRECATED_V2 in commit e52eec13cd6b ("SYSFS: Allow boot
time switching between deprecated and modern sysfs layout") to allow
them to continue to boot properly, and we allowed a boot time parameter
to be used to switch back to the old format if needed.

Over time, the logic that was covered under these config options was
slowly removed from individual driver subsystems successfully, removed,
and the only thing that is now left in the kernel are some changes in
the block layer's representation in sysfs where real directories are
used instead of symlinks like normal.

Because the original changes were done to userspace tools in 2006, and
all distros that use those tools are long end-of-life, and older
non-udev-based systems do not care about the block layer's sysfs
representation, it is time to finally remove this old logic and the
config entries from the kernel.

Cc: Jonathan Corbet 
Cc: "Rafael J. Wysocki" 
Cc: linux-block@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Acked-by: Jens Axboe 
Link: https://lore.kernel.org/r/20230223073326.2073220-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

driver core: fw_devlink: Add DL_FLAG_CYCLE support to device links

2023-02-08T12:37:54+00:00

fw_devlink uses DL_FLAG_SYNC_STATE_ONLY device link flag for two
purposes:

1. To allow a parent device to proxy its child device's dependency on a
   supplier so that the supplier doesn't get its sync_state() callback
   before the child device/consumer can be added and probed. In this
   usage scenario, we need to ignore cycles for ensure correctness of
   sync_state() callbacks.

2. When there are dependency cycles in firmware, we don't know which of
   those dependencies are valid. So, we have to ignore them all wrt
   probe ordering while still making sure the sync_state() callbacks
   come correctly.

However, when detecting dependency cycles, there can be multiple
dependency cycles between two devices that we need to detect. For
example:

A -> B -> A and A -> C -> B -> A.

To detect multiple cycles correct, we need to be able to differentiate
DL_FLAG_SYNC_STATE_ONLY device links used for (1) vs (2) above.

To allow this differentiation, add a DL_FLAG_CYCLE that can be use to
mark use case (2). We can then use the DL_FLAG_CYCLE to decide which
DL_FLAG_SYNC_STATE_ONLY device links to follow when looking for
dependency cycles.

Fixes: 2de9d8e0d2fe ("driver core: fw_devlink: Improve handling of cyclic dependencies")
Signed-off-by: Saravana Kannan 
Tested-by: Colin Foster 
Tested-by: Sudeep Holla 
Tested-by: Douglas Anderson 
Tested-by: Geert Uytterhoeven 
Tested-by: Luca Weiss  # qcom/sm7225-fairphone-fp4
Link: https://lore.kernel.org/r/20230207014207.1678715-6-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman

driver core: device_get_devnode() should take a const *

2023-01-27T12:45:40+00:00

device_get_devnode() should take a constant * to struct device as it
does not modify it in any way, so modify the function definition to do
this and move it out of device.h as it does not need to be exposed to
the whole kernel tree.

Cc: Thomas Gleixner 
Cc: Jason Gunthorpe 
Cc: Ira Weiny 
Cc: Dan Williams 
Cc: Won Chung 
Acked-by: Rafael J. Wysocki 
Reviewed-by: Andy Shevchenko 
Acked-by: Hans de Goede 
Link: https://lore.kernel.org/r/20230111113018.459199-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman