When pulling the recent pinctrl merge, I was surprised by how a
pinctrl-only pull request ended up rebuilding basically the whole
kernel.
The reason for that ended up being that <linux/device.h> included
<linux/pinctrl/devinfo.h>, so any change to that file ended up causing
pretty much every driver out there to be rebuilt.
The reason for that was because 'struct device' has this in it:
#ifdef CONFIG_PINCTRL
struct dev_pin_info *pins;
#endif
but we already avoid header includes for these kinds of things in that
header file, preferring to just use a forward-declaration of the
structure instead. Exactly to avoid this kind of header dependency.
Since some drivers seem to expect that <linux/pinctrl/devinfo.h> header
to come in automatically, move the include to <linux/pinctrl/pinctrl.h>
instead. It might be better to just make the includes more targeted,
but I'm not going to review every driver.
It would definitely be good to have a tool for finding and minimizing
header dependencies automatically - or at least help with them. Right
now we almost certainly end up having way too many of these things, and
it's hard to test every single configuration.
FWIW, you can get a sense of the "hotness" of a header file with something
like this after doing a full build:
find . -name '.*.o.cmd' -print0 |
xargs -0 tail --lines=+2 |
grep -v 'wildcard ' |
tr ' \\' '\n' |
sort | uniq -c | sort -n | less -S
which isn't exact (there are other things in those '*.o.cmd' than just
the dependencies, and the "--lines=+2" only removes the header), but
might a useful approximation.
With this patch, <linux/pinctrl/devinfo.h> drops to "only" having 833
users in the current x86-64 allmodconfig. In contrast, <linux/device.h>
has 14857 build files including it directly or indirectly.
Of course, the headers that absolutely _everybody_ includes (things like
<linux/types.h> etc) get a score of 23000+.
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull driver core updates from Greg KH:
"Here is the set of "big" driver core patches for 4.16-rc1.
The majority of the work here is in the firmware subsystem, with
reworks to try to attempt to make the code easier to handle in the
long run, but no functional change. There's also some tree-wide sysfs
attribute fixups with lots of acks from the various subsystem
maintainers, as well as a handful of other normal fixes and changes.
And finally, some license cleanups for the driver core and sysfs code.
All have been in linux-next for a while with no reported issues"
* tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (48 commits)
device property: Define type of PROPERTY_ENRTY_*() macros
device property: Reuse property_entry_free_data()
device property: Move property_entry_free_data() upper
firmware: Fix up docs referring to FIRMWARE_IN_KERNEL
firmware: Drop FIRMWARE_IN_KERNEL Kconfig option
USB: serial: keyspan: Drop firmware Kconfig options
sysfs: remove DEBUG defines
sysfs: use SPDX identifiers
drivers: base: add coredump driver ops
sysfs: add attribute specification for /sysfs/devices/.../coredump
test_firmware: fix missing unlock on error in config_num_requests_store()
test_firmware: make local symbol test_fw_config static
sysfs: turn WARN() into pr_warn()
firmware: Fix a typo in fallback-mechanisms.rst
treewide: Use DEVICE_ATTR_WO
treewide: Use DEVICE_ATTR_RO
treewide: Use DEVICE_ATTR_RW
sysfs.h: Use octal permissions
component: add debugfs support
bus: simple-pm-bus: convert bool SIMPLE_PM_BUS to tristate
...
This adds the coredump driver operation. When the driver defines it
a coredump file is added in the sysfs folder of the device upon
driver binding. The file is removed when the driver is unbound.
User-space can trigger a coredump for this device by echo'ing to
the coredump file.
Signed-off-by: Arend van Spriel <aspriel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The GPIO 'value' attribute is time critical. A small bench with
'perf record' on the app below shows that 80% of the time spent in
sysfs_kf_seq_show() is spent in memset() for zeroising the buffer.
|--67.48%--sysfs_kf_seq_show
| |
| |--54.40%--memset
| |
| |--11.49%--dev_attr_show
| | |
| | |--10.06%--value_show
| | | |
| | | |--4.75%--sprintf
| | | | |
This patch changes the attribute type to prealloc, eliminating the
need to zeroise the buffer at each read. 'perf record' gives the
following result.
|--42.41%--sysfs_kf_read
| |
| |--39.73%--dev_attr_show
| | |
| | |--38.23%--value_show
| | | |
| | | |--29.22%--sprintf
| | | | |
Test done with the following small app:
int main(int argc, char **argv)
{
int fd = open(argv[1], O_RDONLY);
for (;;) {
int buf[512];
read(fd, buf, 512);
lseek(fd, 0, SEEK_SET);
}
exit(0);
}
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Now that the SPDX tag is in all driver core files, that identifies the
license in a specific and legally-defined manner. So the extra GPL text
wording can be removed as it is no longer needed at all.
This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.
No copyright headers or other non-license-description text was removed.
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Update the driver core files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.
This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull dma-mapping updates from Christoph Hellwig:
- turn dma_cache_sync into a dma_map_ops instance and remove
implementation that purely are dead because the architecture doesn't
support noncoherent allocations
- add a flag for busses that need DMA configuration (Robin Murphy)
* tag 'dma-mapping-4.15' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: turn dma_cache_sync into a dma_map_ops method
sh: make dma_cache_sync a no-op
xtensa: make dma_cache_sync a no-op
unicore32: make dma_cache_sync a no-op
powerpc: make dma_cache_sync a no-op
mn10300: make dma_cache_sync a no-op
microblaze: make dma_cache_sync a no-op
ia64: make dma_cache_sync a no-op
frv: make dma_cache_sync a no-op
x86: make dma_cache_sync a no-op
floppy: consolidate the dummy fd_cacheflush definition
drivers: flag buses which demand DMA configuration
The motivation for this change is to provide a way to work around
a problem with the direct-complete mechanism used for avoiding
system suspend/resume handling for devices in runtime suspend.
The problem is that some middle layer code (the PCI bus type and
the ACPI PM domain in particular) returns positive values from its
system suspend ->prepare callbacks regardless of whether the driver's
->prepare returns a positive value or 0, which effectively prevents
drivers from being able to control the direct-complete feature.
Some drivers need that control, however, and the PCI bus type has
grown its own flag to deal with this issue, but since it is not
limited to PCI, it is better to address it by adding driver flags at
the core level.
To that end, add a driver_flags field to struct dev_pm_info for flags
that can be set by device drivers at the probe time to inform the PM
core and/or bus types, PM domains and so on on the capabilities and/or
preferences of device drivers. Also add two static inline helpers
for setting that field and testing it against a given set of flags
and make the driver core clear it automatically on driver remove
and probe failures.
Define and document two PM driver flags related to the direct-
complete feature: NEVER_SKIP and SMART_PREPARE that can be used,
respectively, to indicate to the PM core that the direct-complete
mechanism should never be used for the device and to inform the
middle layer code (bus types, PM domains etc) that it can only
request the PM core to use the direct-complete mechanism for
the device (by returning a positive value from its ->prepare
callback) if it also has been requested by the driver.
While at it, make the core check pm_runtime_suspended() when
setting power.direct_complete so that it doesn't need to be
checked by ->prepare callbacks.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
We do not want the common dma_configure() pathway to apply
indiscriminately to all devices, since there are plenty of buses which
do not have DMA capability, and if their child devices were used for
DMA API calls it would only be indicative of a driver bug. However,
there are a number of buses for which DMA is implicitly expected even
when not described by firmware - those we whitelist with an automatic
opt-in to dma_configure(), assuming that the DMA address space and the
physical address space are equivalent if not otherwise specified.
Commit 7232888366 ("of: restrict DMA configuration") introduced a
short-term fix by comparing explicit bus types, but this approach is far
from pretty, doesn't scale well, and fails to cope at all with bus
drivers which may be built as modules, like host1x. Let's refine things
by making that opt-in a property of the bus type, which neatly addresses
those problems and lets the decision of whether firmware description of
DMA capability should be optional or mandatory stay internal to the bus
drivers themselves.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull driver core fixes from Greg KH:
"Here are a few small fixes for 4.14-rc4.
The removal of DRIVER_ATTR() was almost completed by 4.14-rc1, but one
straggler made it in through some other tree (odds are, one of
mine...) So there's a simple removal of the last user, and then
finally the macro is removed from the tree.
There's a fix for old crazy udev instances that insist on reloading a
module when it is removed from the kernel due to the new uevents for
bind/unbind. This fixes the reported regression, hopefully some year
in the future we can drop the workaround, once users update to the
latest version, but I'm not holding my breath.
And then there's a build fix for a linker warning, and a buffer
overflow fix to match the PCI fixes you took through the PCI tree in
the same area.
All of these have been in linux-next for a few weeks while I've been
traveling, sorry for the delay"
* tag 'driver-core-4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
driver core: remove DRIVER_ATTR
fpga: altera-cvp: remove DRIVER_ATTR() usage
driver core: platform: Don't read past the end of "driver_override" buffer
base: arch_topology: fix section mismatch build warnings
driver core: suppress sending MODALIAS in UNBIND uevents
There are no classes using the legacy suspend/resume operations in
the tree any more, so drop these operations and update the code
referring to them accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DRIVER_ATTR is no longer in use, and driver authors should be using
DRIVER_ATTR_RW() or DRIVER_ATTR_RO() or DRIVER_ATTR_WO() instead in
order to always get the permissions correct. So remove it so that no
one can use it anymore.
Acked-by: Alan Tull <atull@kernel.org>
Reviewed-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct location as of commit 2728b2d2e5 (PM / core / docs:
Convert sleep states API document to reST).
Fixes: 2728b2d2e5 (PM / core / docs: Convert sleep states API document to reST)
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
As seen from the implementation of the single class shutdown hook this
is not very sound design.
Rename the class shutdown hook to shutdown_pre to make it clear it runs
before the driver shutdown hook.
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 5657933dbb (treewide: Move dma_ops from struct dev_archdata into
struct device) added the dma_ops field to struct device, but did not
update the kerneldoc comment, yielding this warning:
./include/linux/device.h:969: warning: No description found for parameter 'dma_ops'
Add a description and bring a little peace to the world.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Update deprecated references to Documentation/pinctrl.txt since it has been
moved to Documentation/driver-api/pinctl.rst.
Signed-off-by: Ludovic Desroches <ludovic.desroches@o2linux.fr>
Fixes: 5a9b73832e ("pinctrl.txt: move it to the driver-api book")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This merges the bind_unbind driver core feature into the
driver-core-next branch. bind_unbind is a branch so that others can
pull and work off of it safely.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many drivers create additional driver-specific device attributes when
binding to the device, and providing managed version of
device_create_group() will simplify unbinding and error handling in probe
path for such drivers.
Without managed version driver writers either have to mix manual and
managed resources, which is prone to errors, or open-code this function by
providing a wrapper to device_add_group() and use it with devm_add_action()
or devm_add_action_or_reset().
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have helpers that work with NULL terminated array of groups, but many
drivers only create a single supplemental group, and do not want to declare
a group array. Let's provide them with helpers working with a single group.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many drivers create additional driver-specific device attributes when
binding to the device. To avoid them calling SYSFS API directly, let's
export these helpers.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull driver core updates from Greg KH:
"Here is the big driver core update for 4.13-rc1.
The large majority of this is a lot of cleanup of old fields in the
driver core structures and their remaining usages in random drivers.
All of those fixes have been reviewed by the various subsystem
maintainers. There's also some small firmware updates in here, a new
kobject uevent api interface that makes userspace interaction easier,
and a few other minor things.
All of these have been in linux-next for a long while with no reported
issues"
* tag 'driver-core-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (56 commits)
arm: mach-rpc: ecard: fix build error
zram: convert remaining CLASS_ATTR() to CLASS_ATTR_RO()
driver-core: remove struct bus_type.dev_attrs
powerpc: vio_cmo: use dev_groups and not dev_attrs for bus_type
powerpc: vio: use dev_groups and not dev_attrs for bus_type
USB: usbip: convert to use DRIVER_ATTR_RW
s390: drivers: convert to use DRIVER_ATTR_RO/WO
platform: thinkpad_acpi: convert to use DRIVER_ATTR_RO/RW
pcmcia: ds: convert to use DRIVER_ATTR_RO
wireless: ipw2x00: convert to use DRIVER_ATTR_RW
net: ehea: convert to use DRIVER_ATTR_RO
net: caif: convert to use DRIVER_ATTR_RO
TTY: hvc: convert to use DRIVER_ATTR_RW
PCI: pci-driver: convert to use DRIVER_ATTR_WO
IB: nes: convert to use DRIVER_ATTR_RW
HID: hid-core: convert to use DRIVER_ATTR_RO and drv_groups
arm: ecard: fix dev_groups patch typo
tty: serdev: use dev_groups and not dev_attrs for bus_type
sparc: vio: use dev_groups and not dev_attrs for bus_type
hid: intel-ish-hid: use dev_groups and not dev_attrs for bus_type
...
Add a helper function to be used when reusing the device-tree node of
another device.
It is fairly common for drivers to reuse the device-tree node of a
parent (or other ancestor) device when creating class or bus devices
(e.g. gpio chips, i2c adapters, iio chips, spi masters, serdev, phys,
usb root hubs). But reusing a device-tree node may cause problems if the
new device is later probed as for example driver core would currently
attempt to reinitialise an already active associated pinmux
configuration.
Other potential issues include the platform-bus code unconditionally
dropping the device-tree node reference in its device destructor,
reinitialisation of other bus-managed resources such as clocks, and the
recently added DMA-setup in driver core.
Note that for most examples above this is currently not an issue as the
devices are never probed, but this is a problem for the USB bus which
has recently gained device-tree support. This was discovered and
worked-around in a rather ad-hoc fashion by commit dc5878abf4 ("usb:
core: move root hub's device node assignment after it is added to bus")
by not setting the of_node pointer until after the root-hub device has
been registered.
Instead we can allow devices to reuse a device-tree node by setting a
flag in their struct device that can be used by core, bus and driver
code to avoid resources from being over-allocated.
Note that the helper also grabs an extra reference to the device node,
which specifically balances the unconditional put in the platform-device
destructor.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
