- Improve device links cycle detection and breaking. Add more
bindings for device link dependencies.
- Refactor parsing 'no-map' in __reserved_mem_alloc_size()
- Improve DT unittest 'ranges' and 'dma-ranges' test case to check
differing cell sizes
- Various http to https link conversions
- Add a schema check to prevent 'syscon' from being used by itself
without a more specific compatible
- A bunch more DT binding conversions to schema
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Merge tag 'devicetree-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree updates from Rob Herring:
- Improve device links cycle detection and breaking. Add more bindings
for device link dependencies.
- Refactor parsing 'no-map' in __reserved_mem_alloc_size()
- Improve DT unittest 'ranges' and 'dma-ranges' test case to check
differing cell sizes
- Various http to https link conversions
- Add a schema check to prevent 'syscon' from being used by itself
without a more specific compatible
- A bunch more DT binding conversions to schema
* tag 'devicetree-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits)
of: reserved-memory: remove duplicated call to of_get_flat_dt_prop() for no-map node
of: unittest: Use bigger address cells to catch parser regressions
dt-bindings: memory-controllers: Convert mmdc to json-schema
dt-bindings: mtd: Convert imx nand to json-schema
dt-bindings: mtd: Convert gpmi nand to json-schema
dt-bindings: iio: io-channel-mux: Fix compatible string in example code
of: property: Add device link support for pinctrl-0 through pinctrl-8
of: property: Add device link support for multiple DT bindings
dt-bindings: phy: ti: phy-gmii-sel: convert bindings to json-schema
dt-bindings: mux: mux.h: drop a duplicated word
dt-bindings: misc: Convert olpc,xo1.75-ec to json-schema
dt-bindings: aspeed-lpc: Replace HTTP links with HTTPS ones
dt-bindings: drm/bridge: Replace HTTP links with HTTPS ones
drm/tilcdc: Replace HTTP links with HTTPS ones
dt-bindings: iommu: renesas,ipmmu-vmsa: Add r8a774e1 support
dt-bindings: fpga: Replace HTTP links with HTTPS ones
dt-bindings: virtio: Replace HTTP links with HTTPS ones
dt-bindings: media: imx274: Add optional input clock and supplies
dt-bindings: i2c-gpio: Use 'deprecated' keyword on deprecated properties
dt-bindings: interrupt-controller: Fix typos in loongson,liointc.yaml
...
Here is the "big" set of changes to the driver core, and some drivers
using the changes, for 5.9-rc1.
"Biggest" thing in here is the device link exposure in sysfs, to help
to tame the madness that is SoC device tree representations and driver
interactions with it.
Other stuff in here that is interesting is:
- device probe log helper so that drivers can report problems in
a unified way easier.
- devres functions added
- DEVICE_ATTR_ADMIN_* macro added to make it harder to write
incorrect sysfs file permissions
- documentation cleanups
- ability for debugfs to be present in the kernel, yet not
exposed to userspace. Needed for systems that want it
enabled, but do not trust users, so they can still use some
kernel functions that were otherwise disabled.
- other minor fixes and cleanups
The patches outside of drivers/base/ all have acks from the respective
subsystem maintainers to go through this tree instead of theirs.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.9-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 changes to the driver core, and some drivers
using the changes, for 5.9-rc1.
"Biggest" thing in here is the device link exposure in sysfs, to help
to tame the madness that is SoC device tree representations and driver
interactions with it.
Other stuff in here that is interesting is:
- device probe log helper so that drivers can report problems in a
unified way easier.
- devres functions added
- DEVICE_ATTR_ADMIN_* macro added to make it harder to write
incorrect sysfs file permissions
- documentation cleanups
- ability for debugfs to be present in the kernel, yet not exposed to
userspace. Needed for systems that want it enabled, but do not
trust users, so they can still use some kernel functions that were
otherwise disabled.
- other minor fixes and cleanups
The patches outside of drivers/base/ all have acks from the respective
subsystem maintainers to go through this tree instead of theirs.
All of these have been in linux-next with no reported issues"
* tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits)
drm/bridge: lvds-codec: simplify error handling
drm/bridge/sii8620: fix resource acquisition error handling
driver core: add deferring probe reason to devices_deferred property
driver core: add device probe log helper
driver core: Avoid binding drivers to dead devices
Revert "test_firmware: Test platform fw loading on non-EFI systems"
firmware_loader: EFI firmware loader must handle pre-allocated buffer
selftest/firmware: Add selftest timeout in settings
test_firmware: Test platform fw loading on non-EFI systems
driver core: Change delimiter in devlink device's name to "--"
debugfs: Add access restriction option
tracefs: Remove unnecessary debug_fs checks.
driver core: Fix probe_count imbalance in really_probe()
kobject: remove unused KOBJ_MAX action
driver core: Fix sleeping in invalid context during device link deletion
driver core: Add waiting_for_supplier sysfs file for devices
driver core: Add state_synced sysfs file for devices that support it
driver core: Expose device link details in sysfs
driver core: Drop mention of obsolete bus rwsem from kernel-doc
debugfs: file: Remove unnecessary cast in kfree()
...
- make support for dma_ops optional
- move more code out of line
- add generic support for a dma_ops bypass mode
- misc cleanups
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Merge tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- make support for dma_ops optional
- move more code out of line
- add generic support for a dma_ops bypass mode
- misc cleanups
* tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping:
dma-contiguous: cleanup dma_alloc_contiguous
dma-debug: use named initializers for dir2name
powerpc: use the generic dma_ops_bypass mode
dma-mapping: add a dma_ops_bypass flag to struct device
dma-mapping: make support for dma ops optional
dma-mapping: inline the fast path dma-direct calls
dma-mapping: move the remaining DMA API calls out of line
* pm-em:
OPP: refactor dev_pm_opp_of_register_em() and update related drivers
Documentation: power: update Energy Model description
PM / EM: change name of em_pd_energy to em_cpu_energy
PM / EM: remove em_register_perf_domain
PM / EM: add support for other devices than CPUs in Energy Model
PM / EM: update callback structure and add device pointer
PM / EM: introduce em_dev_register_perf_domain function
PM / EM: change naming convention from 'capacity' to 'performance'
* pm-core:
mmc: jz4740: Use pm_ptr() macro
PM: Make *_DEV_PM_OPS macros use __maybe_unused
PM: core: introduce pm_ptr() macro
During probe every time driver gets resource it should usually check for
error printk some message if it is not -EPROBE_DEFER and return the error.
This pattern is simple but requires adding few lines after any resource
acquisition code, as a result it is often omitted or implemented only
partially.
dev_err_probe helps to replace such code sequences with simple call,
so code:
if (err != -EPROBE_DEFER)
dev_err(dev, ...);
return err;
becomes:
return dev_err_probe(dev, err, ...);
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200713144324.23654-2-a.hajda@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several IOMMU drivers have a bypass mode where they can use a direct
mapping if the devices DMA mask is large enough. Add generic support
to the core dma-mapping code to do that to switch those drivers to
a common solution.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Avoid the overhead of the dma ops support for tiny builds that only
use the direct mapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
It's helpful to be able to look at device link details from sysfs. So,
expose it in sysfs.
Say device-A is supplier of device-B. These are the additional files
this patch would create:
/sys/class/devlink/device-A:device-B/
auto_remove_on
consumer/ -> .../device-B/
runtime_pm
status
supplier/ -> .../device-A/
sync_state_only
/sys/devices/.../device-A/
consumer:device-B/ -> /sys/class/devlink/device-A:device-B/
/sys/devices/.../device-B/
supplier:device-A/ -> /sys/class/devlink/device-A:device-B/
That way:
To get a list of all the device link in the system:
ls /sys/class/devlink/
To get the consumer names and links of a device:
ls -d /sys/devices/.../device-X/consumer:*
To get the supplier names and links of a device:
ls -d /sys/devices/.../device-X/supplier:*
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200521191800.136035-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With the earlier patch in this series, all devices that deferred probe
due to fw_devlink_pause() will have their probes delayed till the
deferred probe thread is kicked off during late_initcall. This will also
affect all their consumers.
This delayed probing in unnecessary. So this patch just keeps track of
the devices that had their probe deferred due to fw_devlink_pause() and
attempts to probe them once during fw_devlink_resume().
Fixes: 716a7a2596 ("driver core: fw_devlink: Add support for batching fwnode parsing")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The defer_sync field is used as a hook to add the device to the
deferred_sync list. Rename it so that it's more meaningful for the next
patch that'll also use this field as a hook to a deferred_fw_devlink
list.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Functions are declared 'extern' implicitly by the compiler. There's no
reason to prepend every prototype with it. Remove the 'extern' keyword
from all function declarations in linux/device.h.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200629065008.27620-4-brgl@bgdev.pl
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A common pattern for using plain DEVICE_ATTR() instead of
DEVICE_ATTR_RO() and DEVICE_ATTR_RW() is for attributes that want to
limit read to only root. I.e. many users of DEVICE_ATTR() are
specifying 0400 or 0600 for permissions.
Given the expectation that CAP_SYS_ADMIN is needed to access these
sensitive attributes and an explicit helper with the _ADMIN_ identifier
for DEVICE_ATTR_ADMIN_{RO,RW}.
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/159312906372.1850128.11611897078988158727.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for other devices than CPUs. The registration function
does not require a valid cpumask pointer and is ready to handle new
devices. Some of the internal structures has been reorganized in order to
keep consistent view (like removing per_cpu pd pointers).
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
DT implementation of fw_devlink needs this function to detect cycles. So
make it available.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
All external users of device_create_vargs are gone, so remove it and
open code it in the only caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Including:
- ARM-SMMU support for the TLB range invalidation command in
SMMUv3.2.
- ARM-SMMU introduction of command batching helpers to batch up
CD and ATC invalidation.
- ARM-SMMU support for PCI PASID, along with necessary PCI
symbol exports.
- Introduce a generic (actually rename an existing) IOMMU
related pointer in struct device and reduce the IOMMU related
pointers.
- Some fixes for the OMAP IOMMU driver to make it build on 64bit
architectures.
- Various smaller fixes and improvements.
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Merge tag 'iommu-updates-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
- ARM-SMMU support for the TLB range invalidation command in SMMUv3.2
- ARM-SMMU introduction of command batching helpers to batch up CD and
ATC invalidation
- ARM-SMMU support for PCI PASID, along with necessary PCI symbol
exports
- Introduce a generic (actually rename an existing) IOMMU related
pointer in struct device and reduce the IOMMU related pointers
- Some fixes for the OMAP IOMMU driver to make it build on 64bit
architectures
- Various smaller fixes and improvements
* tag 'iommu-updates-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (39 commits)
iommu: Move fwspec->iommu_priv to struct dev_iommu
iommu/virtio: Use accessor functions for iommu private data
iommu/qcom: Use accessor functions for iommu private data
iommu/mediatek: Use accessor functions for iommu private data
iommu/renesas: Use accessor functions for iommu private data
iommu/arm-smmu: Use accessor functions for iommu private data
iommu/arm-smmu: Refactor master_cfg/fwspec usage
iommu/arm-smmu-v3: Use accessor functions for iommu private data
iommu: Introduce accessors for iommu private data
iommu/arm-smmu: Fix uninitilized variable warning
iommu: Move iommu_fwspec to struct dev_iommu
iommu: Rename struct iommu_param to dev_iommu
iommu/tegra-gart: Remove direct access of dev->iommu_fwspec
drm/msm/mdp5: Remove direct access of dev->iommu_fwspec
ACPI/IORT: Remove direct access of dev->iommu_fwspec
iommu: Define dev_iommu_fwspec_get() for !CONFIG_IOMMU_API
iommu/virtio: Reject IOMMU page granule larger than PAGE_SIZE
iommu/virtio: Fix freeing of incomplete domains
iommu/virtio: Fix sparse warning
iommu/vt-d: Add build dependency on IOASID
...
Move the iommu_fwspec pointer in struct device into struct dev_iommu.
This is a step in the effort to reduce the iommu related pointers in
struct device to one.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Will Deacon <will@kernel.org> # arm-smmu
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200326150841.10083-7-joro@8bytes.org
Add a helper to change the owner of a device's sysfs entries. This
needs to happen when the ownership of a device is changed, e.g. when
moving network devices between network namespaces.
This function will be used to correctly account for ownership changes,
e.g. when moving network devices between network namespaces.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
device.h has everything and the kitchen sink when it comes to struct
device things, so split out the struct driver things things to a
separate .h file to make things easier to maintain and manage over time.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191209193303.1694546-7-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
device.h has everything and the kitchen sink when it comes to struct
device things, so split out the struct class things things to a separate
.h file to make things easier to maintain and manage over time.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191209193303.1694546-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
device.h has everything and the kitchen sink when it comes to struct
device things, so split out the struct bus things things to a separate
.h file to make things easier to maintain and manage over time.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191209193303.1694546-5-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
device.h has everything and the kitchen sink when it comes to struct
device things, so split out the printk-specific things to a separate .h
file to make things easier to maintain and manage over time.
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191209193303.1694546-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The devtmpfs functions do not need to be in device.h as only the driver
core uses them, so move them to the private .h file for the driver core.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191209193303.1694546-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In devtmpfs, do_mount() can be called directly instead of complex wrapping
by ksys_mount():
- the first and third arguments are const strings in the kernel,
and do not need to be copied over from userspace;
- the fifth argument is NULL, and therefore no page needs to be
copied over from userspace;
- the second and fourth argument are passed through anyway.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
- improve dma-debug scalability (Eric Dumazet)
- tiny dma-debug cleanup (Dan Carpenter)
- check for vmap memory in dma_map_single (Kees Cook)
- check for dma_addr_t overflows in dma-direct when using
DMA offsets (Nicolas Saenz Julienne)
- switch the x86 sta2x11 SOC to use more generic DMA code
(Nicolas Saenz Julienne)
- fix arm-nommu dma-ranges handling (Vladimir Murzin)
- use __initdata in CMA (Shyam Saini)
- replace the bus dma mask with a limit (Nicolas Saenz Julienne)
- merge the remapping helpers into the main dma-direct flow (me)
- switch xtensa to the generic dma remap handling (me)
- various cleanups around dma_capable (me)
- remove unused dev arguments to various dma-noncoherent helpers (me)
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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- improve dma-debug scalability (Eric Dumazet)
- tiny dma-debug cleanup (Dan Carpenter)
- check for vmap memory in dma_map_single (Kees Cook)
- check for dma_addr_t overflows in dma-direct when using DMA offsets
(Nicolas Saenz Julienne)
- switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas
Saenz Julienne)
- fix arm-nommu dma-ranges handling (Vladimir Murzin)
- use __initdata in CMA (Shyam Saini)
- replace the bus dma mask with a limit (Nicolas Saenz Julienne)
- merge the remapping helpers into the main dma-direct flow (me)
- switch xtensa to the generic dma remap handling (me)
- various cleanups around dma_capable (me)
- remove unused dev arguments to various dma-noncoherent helpers (me)
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux:
* tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits)
dma-mapping: treat dev->bus_dma_mask as a DMA limit
dma-direct: exclude dma_direct_map_resource from the min_low_pfn check
dma-direct: don't check swiotlb=force in dma_direct_map_resource
dma-debug: clean up put_hash_bucket()
powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys
dma-direct: avoid a forward declaration for phys_to_dma
dma-direct: unify the dma_capable definitions
dma-mapping: drop the dev argument to arch_sync_dma_for_*
x86/PCI: sta2x11: use default DMA address translation
dma-direct: check for overflows on 32 bit DMA addresses
dma-debug: increase HASH_SIZE
dma-debug: reorder struct dma_debug_entry fields
xtensa: use the generic uncached segment support
dma-mapping: merge the generic remapping helpers into dma-direct
dma-direct: provide mmap and get_sgtable method overrides
dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages
dma-direct: remove __dma_direct_free_pages
usb: core: Remove redundant vmap checks
kernel: dma-contiguous: mark CMA parameters __initdata/__initconst
dma-debug: add a schedule point in debug_dma_dump_mappings()
...
Using a mask to represent bus DMA constraints has a set of limitations.
The biggest one being it can only hold a power of two (minus one). The
DMA mapping code is already aware of this and treats dev->bus_dma_mask
as a limit. This quirk is already used by some architectures although
still rare.
With the introduction of the Raspberry Pi 4 we've found a new contender
for the use of bus DMA limits, as its PCIe bus can only address the
lower 3GB of memory (of a total of 4GB). This is impossible to represent
with a mask. To make things worse the device-tree code rounds non power
of two bus DMA limits to the next power of two, which is unacceptable in
this case.
In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all
over the tree and treat it as such. Note that dev->bus_dma_limit should
contain the higher accessible DMA address.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Before this change, if a device is waiting on suppliers, it's assumed
that all those suppliers are needed for the device to probe
successfully. This change allows marking a devices as waiting only on
optional suppliers. This allows a device to wait on suppliers (and link
to them as soon as they are available) without preventing the device
from being probed.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Parent devices might need to create "proxy" device links from themselves
to supplier devices to make sure the supplier devices don't get a
sync_state() before the child consumer devices get a chance to add
device links to the supplier devices.
However, the parent device has no real dependency on the supplier device
and probing, suspend/resume or runtime PM don't need to be affected by
the supplier device. To capture these cases, create a SYNC_STATE_ONLY
device link flag that only affects sync_state() behavior and doesn't
affect probing, suspend/resume or runtime PM.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This sync_state driver/bus callback is called once all the consumers
of a supplier have probed successfully.
This allows the supplier device's driver/bus to sync the supplier
device's state to the software state with the guarantee that all the
consumers are actively managing the resources provided by the supplier
device.
To maintain backwards compatibility and ease transition from existing
frameworks and resource cleanup schemes, late_initcall_sync is the
earliest when the sync_state callback might be called.
There is no upper bound on the time by which the sync_state callback
has to be called. This is because if a consumer device never probes,
the supplier has to maintain its resources in the state left by the
bootloader. For example, if the bootloader leaves the display
backlight at a fixed voltage and the backlight driver is never probed,
you don't want the backlight to ever be turned off after boot up.
Also, when multiple devices are added after kernel init, some
suppliers could be added before their consumer devices get added. In
these instances, the supplier devices could get their sync_state
callback called right after they probe because the consumers devices
haven't had a chance to create device links to the suppliers.
To handle this correctly, this change also provides APIs to
pause/resume sync state callbacks so that when multiple devices are
added, their sync_state callback evaluation can be postponed to happen
after all of them are added.
kbuild test robot reported missing documentation for device.state_synced
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-5-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The firmware corresponding to a device (dev.fwnode) might be able to
provide functional dependency information between a device and its
supplier and consumer devices. Tracking this functional dependency
allows optimizing device probe order and informing a supplier when all
its consumers have probed (and thereby actively managing their
resources).
The existing device links feature allows tracking and using
supplier-consumer relationships. So, this patch adds the add_links()
fwnode callback to allow firmware to create device links for each
device as the device is added.
However, when consumer devices are added, they might not have a supplier
device to link to despite needing mandatory resources/functionality from
one or more suppliers. A waiting_for_suppliers list is created to track
such consumers and retry linking them when new devices get added.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the big set of USB patches for 5.4-rc1.
Two major chunks of code are moving out of the tree and into the staging
directory, uwb and wusb (wireless USB support), because there are no
devices that actually use this protocol anymore, and what we have today
probably doesn't work at all given that the maintainers left many many
years ago. So move it to staging where it will be removed in a few
releases if no one screams.
Other than that, lots of little things. The usual gadget and xhci and
usb serial driver updates, along with a bunch of sysfs file cleanups due
to the driver core changes to support that. Nothing really major, just
constant forward progress.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH:
"Here is the big set of USB patches for 5.4-rc1.
Two major chunks of code are moving out of the tree and into the
staging directory, uwb and wusb (wireless USB support), because there
are no devices that actually use this protocol anymore, and what we
have today probably doesn't work at all given that the maintainers
left many many years ago. So move it to staging where it will be
removed in a few releases if no one screams.
Other than that, lots of little things. The usual gadget and xhci and
usb serial driver updates, along with a bunch of sysfs file cleanups
due to the driver core changes to support that. Nothing really major,
just constant forward progress.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (159 commits)
USB: usbcore: Fix slab-out-of-bounds bug during device reset
usb: cdns3: Remove redundant dev_err call in cdns3_probe()
USB: rio500: Fix lockdep violation
USB: rio500: simplify locking
usb: mtu3: register a USB Role Switch for dual role mode
usb: common: add USB GPIO based connection detection driver
usb: common: create Kconfig file
usb: roles: get usb-role-switch from parent
usb: roles: Add fwnode_usb_role_switch_get() function
device connection: Add fwnode_connection_find_match()
usb: roles: Introduce stubs for the exiting functions in role.h
dt-bindings: usb: mtu3: add properties about USB Role Switch
dt-bindings: usb: add binding for USB GPIO based connection detection driver
dt-bindings: connector: add optional properties for Type-B
dt-binding: usb: add usb-role-switch property
usbip: Implement SG support to vhci-hcd and stub driver
usb: roles: intel: Enable static DRD mode for role switch
xhci-ext-caps.c: Add property to disable Intel SW switch
usb: dwc3: remove generic PHY calibrate() calls
usb: core: phy: add support for PHY calibration
...
The fwnode_connection_find_match() function is exactly the
same as device_connection_find_match(), except it takes
struct fwnode_handle as parameter instead of struct device.
That allows locating device connections before the device
entries have been created.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1567070558-29417-7-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 5302dd7dd0.
Based on a lot of email and in-person discussions, this patch series is
being reworked to address a number of issues that were pointed out that
needed to be taken care of before it should be merged. It will be
resubmitted with those changes hopefully soon.
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 134b23eec9.
Based on a lot of email and in-person discussions, this patch series is
being reworked to address a number of issues that were pointed out that
needed to be taken care of before it should be merged. It will be
resubmitted with those changes hopefully soon.
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 8f8184d6bf.
Based on a lot of email and in-person discussions, this patch series is
being reworked to address a number of issues that were pointed out that
needed to be taken care of before it should be merged. It will be
resubmitted with those changes hopefully soon.
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the warnings for parameter named as "driver" instead of the actual "drv"
in the comments as reported by the kbuild robot.
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20190809102033.28463-1-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Persistent tag for others to pull this branch from
This is the first patch in a longer series that adds the ability for the
driver core to create and remove a list of attribute groups
automatically when the device is bound/unbound from a specific driver.
See:
https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org
for details on this patch, and examples of how to use it in other
drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'dev_groups_all_drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core into usb-next
dev_groups added to struct driver
Persistent tag for others to pull this branch from
This is the first patch in a longer series that adds the ability for the
driver core to create and remove a list of attribute groups
automatically when the device is bound/unbound from a specific driver.
See:
https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org
for details on this patch, and examples of how to use it in other
drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Persistent tag for others to pull this branch from
This is the first patch in a longer series that adds the ability for the
driver core to create and remove a list of attribute groups
automatically when the device is bound/unbound from a specific driver.
See:
https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org
for details on this patch, and examples of how to use it in other
drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'dev_groups_all_drivers' into driver-core-next
dev_groups added to struct driver
Persistent tag for others to pull this branch from
This is the first patch in a longer series that adds the ability for the
driver core to create and remove a list of attribute groups
automatically when the device is bound/unbound from a specific driver.
See:
https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org
for details on this patch, and examples of how to use it in other
drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add the ability for the driver core to create and remove a list of
attribute groups automatically when the device is bound/unbound from a
specific driver.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Richard Gong <richard.gong@linux.intel.com>
Link: https://lore.kernel.org/r/20190731124349.4474-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This sync_state driver/bus callback is called once all the consumers
of a supplier have probed successfully.
This allows the supplier device's driver/bus to sync the supplier
device's state to the software state with the guarantee that all the
consumers are actively managing the resources provided by the supplier
device.
To maintain backwards compatibility and ease transition from existing
frameworks and resource cleanup schemes, late_initcall_sync is the
earliest when the sync_state callback might be called.
There is no upper bound on the time by which the sync_state callback
has to be called. This is because if a consumer device never probes,
the supplier has to maintain its resources in the state left by the
bootloader. For example, if the bootloader leaves the display
backlight at a fixed voltage and the backlight driver is never probed,
you don't want the backlight to ever be turned off after boot up.
Also, when multiple devices are added after kernel init, some
suppliers could be added before their consumer devices get added. In
these instances, the supplier devices could get their sync_state
callback called right after they probe because the consumers devices
haven't had a chance to create device links to the suppliers.
To handle this correctly, this change also provides APIs to
pause/resume sync state callbacks so that when multiple devices are
added, their sync_state callback evaluation can be postponed to happen
after all of them are added.
kbuild test robot reported missing documentation for device.state_synced
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190731221721.187713-5-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver core/bus adding supplier-consumer dependencies by default
enables functional dependencies to be tracked correctly even when the
consumer devices haven't had their drivers registered or loaded (if they
are modules).
However, when the bus incorrectly adds dependencies that it shouldn't
have added, the devices might never probe.
For example, if device-C is a consumer of device-S and they have
phandles to each other in DT, the following could happen:
1. Device-S get added first.
2. The bus add_links() callback will (incorrectly) try to link it as
a consumer of device-C.
3. Since device-C isn't present, device-S will be put in
"waiting-for-supplier" list.
4. Device-C gets added next.
5. All devices in "waiting-for-supplier" list are retried for linking.
6. Device-S gets linked as consumer to Device-C.
7. The bus add_links() callback will (correctly) try to link it as
a consumer of device-S.
8. This isn't allowed because it would create a cyclic device links.
Neither devices will get probed since the supplier is marked as
dependent on the consumer. And the consumer will never probe because the
consumer can't get resources from the supplier.
Without this patch, things stay in this broken state. However, with this
patch, the execution will continue like this:
9. Device-C's driver is loaded.
10. Device-C's driver removes Device-S as a consumer of Device-C.
11. Device-C's driver adds Device-C as a consumer of Device-S.
12. Device-S probes.
14. Device-C probes.
kbuild test robot reported missing documentation for device.has_edit_links
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190731221721.187713-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When devices are added, the bus might want to create device links to track
functional dependencies between supplier and consumer devices. This
tracking of supplier-consumer relationship allows optimizing device probe
order and tracking whether all consumers of a supplier are active. The
add_links bus callback is added to support this.
However, when consumer devices are added, they might not have a supplier
device to link to despite needing mandatory resources/functionality from
one or more suppliers. A waiting_for_suppliers list is created to track
such consumers and retry linking them when new devices get added.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190731221721.187713-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
