Commit Graph

429 Commits

Author SHA1 Message Date
Linus Torvalds
2857676045 Merge tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull overflow updates from Kees Cook:
 "This adds the new overflow checking helpers and adds them to the
  2-factor argument allocators. And this adds the saturating size
  helpers and does a treewide replacement for the struct_size() usage.
  Additionally this adds the overflow testing modules to make sure
  everything works.

  I'm still working on the treewide replacements for allocators with
  "simple" multiplied arguments:

     *alloc(a * b, ...) -> *alloc_array(a, b, ...)

  and

     *zalloc(a * b, ...) -> *calloc(a, b, ...)

  as well as the more complex cases, but that's separable from this
  portion of the series. I expect to have the rest sent before -rc1
  closes; there are a lot of messy cases to clean up.

  Summary:

   - Introduce arithmetic overflow test helper functions (Rasmus)

   - Use overflow helpers in 2-factor allocators (Kees, Rasmus)

   - Introduce overflow test module (Rasmus, Kees)

   - Introduce saturating size helper functions (Matthew, Kees)

   - Treewide use of struct_size() for allocators (Kees)"

* tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  treewide: Use struct_size() for devm_kmalloc() and friends
  treewide: Use struct_size() for vmalloc()-family
  treewide: Use struct_size() for kmalloc()-family
  device: Use overflow helpers for devm_kmalloc()
  mm: Use overflow helpers in kvmalloc()
  mm: Use overflow helpers in kmalloc_array*()
  test_overflow: Add memory allocation overflow tests
  overflow.h: Add allocation size calculation helpers
  test_overflow: Report test failures
  test_overflow: macrofy some more, do more tests for free
  lib: add runtime test of check_*_overflow functions
  compiler.h: enable builtin overflow checkers and add fallback code
2018-06-06 17:27:14 -07:00
Linus Torvalds
ec064d3c6b Merge tag 'driver-core-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the driver core patchset for 4.18-rc1.

  The large chunk of these are firmware core documentation and api
  updates. Nothing major there, just better descriptions for others to
  be able to understand the firmware code better. There's also a user
  for a new firmware api call.

  Other than that, there are some minor updates for debugfs, kernfs, and
  the driver core itself.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
  driver core: hold dev's parent lock when needed
  driver-core: return EINVAL error instead of BUG_ON()
  driver core: add __printf verification to device_create_groups_vargs
  mm: memory_hotplug: use put_device() if device_register fail
  base: core: fix typo 'can by' to 'can be'
  debugfs: inode: debugfs_create_dir uses mode permission from parent
  debugfs: Re-use kstrtobool_from_user()
  Documentation: clarify firmware_class provenance and why we can't rename the module
  Documentation: remove stale firmware API reference
  Documentation: fix few typos and clarifications for the firmware loader
  ath10k: re-enable the firmware fallback mechanism for testmode
  ath10k: use firmware_request_nowarn() to load firmware
  firmware: add firmware_request_nowarn() - load firmware without warnings
  firmware_loader: make firmware_fallback_sysfs() print more useful
  firmware_loader: move kconfig FW_LOADER entries to its own file
  firmware_loader: replace ---help--- with help
  firmware_loader: enhance Kconfig documentation over FW_LOADER
  firmware_loader: document firmware_sysfs_fallback()
  firmware: rename fw_sysfs_fallback to firmware_fallback_sysfs()
  firmware: use () to terminate kernel-doc function names
  ...
2018-06-05 16:29:19 -07:00
Kees Cook
2509b561f7 device: Use overflow helpers for devm_kmalloc()
Use the overflow helpers both in existing multiplication-using inlines as
well as the addition-overflow case in the core allocation routine.

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05 12:16:51 -07:00
Martin Liu
8c97a46af0 driver core: hold dev's parent lock when needed
SoC have internal I/O buses that can't be proved for devices. The
devices on the buses can be accessed directly without additinal
configuration required. This type of bus is represented as
"simple-bus". In some platforms, we name "soc" with "simple-bus"
attribute and many devices are hooked under it described in DT
(device tree).

In commit bf74ad5bc4 ("Hold the device's parent's lock during
probe and remove") to solve USB subsystem lock sequence since
USB device's characteristic. Thus "soc" needs to be locked
whenever a device and driver's probing happen under "soc" bus.
During this period, an async driver tries to probe a device which
is under the "soc" bus would be blocked until previous driver
finish the probing and release "soc" lock. And the next probing
under the "soc" bus need to wait for async finish. Because of
that, driver's async probe for init time improvement will be
shadowed.

Since many devices don't have USB devices' characteristic, they
actually don't need parent's lock. Thus, we introduce a lock flag
in bus_type struct and driver core would lock the parent lock base
on the flag. For USB, we set this flag in usb_bus_type to keep
original lock behavior in driver core.

Async probe could have more benefit after this patch.

Signed-off-by: Martin Liu <liumartin@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-31 10:12:07 +02:00
Christoph Hellwig
f068fe3170 core, dma-direct: add a flag 32-bit dma limits
Various PCI bridges (VIA PCI, Xilinx PCIe) limit DMA to only 32-bits
even if the device itself supports more.  Add a single bit flag to
struct device (to be moved into the dma extension once we get to it)
to flag such devices and reject larger DMA to them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-28 12:46:54 +02:00
Christoph Hellwig
3d6ce86ee7 drivers: remove force dma flag from buses
With each bus implementing its own DMA configuration callback, there is no
need for bus to explicitly set the force_dma flag.  Modify the
of_dma_configure function to accept an input parameter which specifies if
implicit DMA configuration is required when it is not described by the
firmware.

Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>  # PCI parts
Reviewed-by: Rob Herring <robh@kernel.org>
[hch: tweaked the changelog a bit]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-03 16:25:08 +02:00
Nipun Gupta
07397df29e dma-mapping: move dma configuration to bus infrastructure
ACPI/OF support for configuration of DMA is a bus specific aspect, and
thus should be configured by the bus.  Introduces a 'dma_configure' bus
method so that busses can control their DMA capabilities.

Also update the PCI, Platform, ACPI and host1x buses to use the new
method.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>  # PCI parts
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[hch: simplified host1x_dma_configure based on a comment from Thierry,
      rewrote changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-03 16:22:18 +02:00
Arend van Spriel
ed4564babe drivers: change struct device_driver::coredump() return type to void
Upon submitting a patch for mwifiex [1] it was discussed whether this
callback function could fail. To keep things simple there is no need
for the error code so the driver can do the task synchronous or not
without worries. Currently the device driver core already ignores the
return value so changing it to void.

[1] https://patchwork.kernel.org/patch/10231933/

Signed-off-by: Arend van Spriel <aspriel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-19 09:48:32 +02:00
Linus Torvalds
38047d5c26 Merge tag 'driver-core-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 4.17-rc1.

  There's really not much here, just a bunch of firmware code
  refactoring from Luis as he attempts to wrangle that codebase into
  something that is managable, along with a bunch of userspace tests for
  it. Other than that, a handful of small bugfixes and reverts of things
  that didn't work out.

  Full details are in the shortlog, it's not all that much.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (30 commits)
  drivers: base: remove check for callback in coredump_store()
  mt7601u: use firmware_request_cache() to address cache on reboot
  firmware: add firmware_request_cache() to help with cache on reboot
  firmware: fix typo on pr_info_once() when ignore_sysfs_fallback is used
  firmware: explicitly include vmalloc.h
  firmware: ensure the firmware cache is not used on incompatible calls
  test_firmware: modify custom fallback tests to use unique files
  firmware: add helper to check to see if fw cache is setup
  firmware: fix checking for return values for fw_add_devm_name()
  rename: _request_firmware_load() fw_load_sysfs_fallback()
  test_firmware: test three firmware kernel configs using a proc knob
  test_firmware: expand on library with shared helpers
  firmware: enable to force disable the fallback mechanism at run time
  firmware: enable run time change of forcing fallback loader
  firmware: move firmware loader into its own directory
  firmware: split firmware fallback functionality into its own file
  firmware: move loading timeout under struct firmware_fallback_config
  firmware: use helpers for setting up a temporary cache timeout
  firmware: simplify CONFIG_FW_LOADER_USER_HELPER_FALLBACK further
  drivers: base: add description for .coredump() callback
  ...
2018-04-04 19:41:45 -07:00
Linus Torvalds
ac9053d2dc Merge tag 'usb-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY updates from Greg KH:
 "Here is the big set of USB and PHY driver patches for 4.17-rc1.

  Lots of USB typeC work happened this round, with code moving from the
  staging directory into the "real" part of the kernel, as well as new
  infrastructure being added to be able to handle the different types of
  "roles" that typeC requires.

  There is also the normal huge set of USB gadget controller and driver
  updates, along with XHCI changes, and a raft of other tiny fixes all
  over the USB tree. And the PHY driver updates are merged in here as
  well as they interacted with the USB drivers in some places.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (250 commits)
  Revert "USB: serial: ftdi_sio: add Id for Physik Instrumente E-870"
  usb: musb: gadget: misplaced out of bounds check
  usb: chipidea: imx: Fix ULPI on imx53
  usb: chipidea: imx: Cleanup ci_hdrc_imx_platform_flag
  usb: chipidea: usbmisc: small clean up
  usb: chipidea: usbmisc: evdo can be set e/o reset
  usb: chipidea: usbmisc: evdo is only specific to OTG port
  USB: serial: ftdi_sio: add Id for Physik Instrumente E-870
  usb: dwc3: gadget: never call ->complete() from ->ep_queue()
  usb: gadget: udc: core: update usb_ep_queue() documentation
  usb: host: Remove the deprecated ATH79 USB host config options
  usb: roles: Fix return value check in intel_xhci_usb_probe()
  USB: gadget: f_midi: fixing a possible double-free in f_midi
  usb: core: Add USB_QUIRK_DELAY_CTRL_MSG to usbcore quirks
  usb: core: Copy parameter string correctly and remove superfluous null check
  USB: announce bcdDevice as well as idVendor, idProduct.
  USB:fix USB3 devices behind USB3 hubs not resuming at hibernate thaw
  usb: hub: Reduce warning to notice on power loss
  USB: serial: ftdi_sio: add support for Harman FirmwareHubEmulator
  USB: serial: cp210x: add ELDAT Easywave RX09 id
  ...
2018-04-04 17:55:35 -07:00
Heikki Krogerus
f2d9b66d84 drivers: base: Unified device connection lookup
Several frameworks - clk, gpio, phy, pmw, etc. - maintain
lookup tables for describing connections and provide custom
API for handling them. This introduces a single generic
lookup table and API for the connections.

The motivation for this commit is centralizing the
connection lookup, but the goal is to ultimately extract the
connection descriptions also from firmware by using the
fwnode_graph_* functions and other mechanisms that are
available.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22 13:10:29 +01:00
Arend van Spriel
8ddfb47294 drivers: base: add description for .coredump() callback
Commit 3c47d19ff4 ("drivers: base: add coredump driver ops") added
a new callback in struct device_driver, but not a kerneldoc description
so here it is.

Fixes: 3c47d19ff4 ("drivers: base: add coredump driver ops")
Signed-off-by: Arend van Spriel <aspriel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 18:21:27 +01:00
Lukas Wunner
ead18c23c2 driver core: Introduce device links reference counting
If device_link_add() is invoked multiple times with the same supplier
and consumer combo, it will create the link on first addition and
return a pointer to the already existing link on all subsequent
additions.

The semantics for device_link_del() are quite different, it deletes
the link unconditionally, so multiple invocations are not allowed.

In other words, this snippet ...

    struct device *dev1, *dev2;
    struct device_link *link1, *link2;

    link1 = device_link_add(dev1, dev2, 0);
    link2 = device_link_add(dev1, dev2, 0);

    device_link_del(link1);
    device_link_del(link2);

... causes the following crash:

    WARNING: CPU: 4 PID: 2686 at drivers/base/power/runtime.c:1611 pm_runtime_drop_link+0x40/0x50
    [...]
    list_del corruption, 0000000039b800a4->prev is LIST_POISON2 (00000000ecf79852)
    kernel BUG at lib/list_debug.c:50!

The issue isn't as arbitrary as it may seem:  Imagine a device link
which is added in both the supplier's and the consumer's ->probe hook.
The two drivers can't just call device_link_del() in their ->remove hook
without coordination.

Fix by counting multiple additions and dropping the device link only
when the last addition is unwound.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-27 18:10:42 +01:00
Linus Torvalds
23c35f48f5 pinctrl: remove include file from <linux/device.h>
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>
2018-02-03 12:10:09 -08:00
Linus Torvalds
47fcc0360c Merge tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
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
  ...
2018-02-01 10:00:28 -08:00
Arend van Spriel
3c47d19ff4 drivers: base: add coredump driver ops
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>
2018-01-23 09:47:05 +01:00
Christophe Leroy
7fda9100bb gpio: sysfs: change 'value' attribute to prealloc
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>
2017-12-20 10:28:05 +01:00
Greg Kroah-Hartman
3282570990 driver core: Remove redundant license text
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>
2017-12-07 18:36:44 +01:00
Greg Kroah-Hartman
989d42e85d driver core: add SPDX identifiers to all driver core files
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>
2017-12-07 18:36:43 +01:00
Linus Torvalds
e37e0ee019 Merge tag 'dma-mapping-4.15' of git://git.infradead.org/users/hch/dma-mapping
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
2017-11-14 16:54:12 -08:00
Rafael J. Wysocki
08810a4119 PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags
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>
2017-11-06 13:55:30 +01:00
Rafael J. Wysocki
a2ab5fc415 Merge branch 'pm-sleep' into pm-core 2017-10-21 13:09:18 +02:00
Robin Murphy
d89e2378a9 drivers: flag buses which demand DMA configuration
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>
2017-10-19 16:34:52 +02:00
Linus Torvalds
c4142ed602 Merge tag 'driver-core-4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
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
2017-10-03 08:57:07 -07:00
Rafael J. Wysocki
a380f2edef PM / core: Drop legacy class suspend/resume operations
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>
2017-09-25 23:58:37 +02:00