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2021-07-05Merge tag 'driver-core-5.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core changes from Greg KH: "Here is the small set of driver core and debugfs updates for 5.14-rc1. Included in here are: - debugfs api cleanups (touched some drivers) - devres updates - tiny driver core updates and tweaks Nothing major in here at all, and all have been in linux-next for a while with no reported issues" * tag 'driver-core-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (27 commits) docs: ABI: testing: sysfs-firmware-memmap: add some memmap types. devres: Enable trace events devres: No need to call remove_nodes() when there none present devres: Use list_for_each_safe_from() in remove_nodes() devres: Make locking straight forward in release_nodes() kernfs: move revalidate to be near lookup drivers/base: Constify static attribute_group structs firmware_loader: remove unneeded 'comma' macro devcoredump: remove contact information driver core: Drop helper devm_platform_ioremap_resource_wc() component: Rename 'dev' to 'parent' component: Drop 'dev' argument to component_match_realloc() device property: Don't check for NULL twice in the loops driver core: auxiliary bus: Fix typo in the docs drivers/base/node.c: make CACHE_ATTR define static DEVICE_ATTR_RO debugfs: remove return value of debugfs_create_ulong() debugfs: remove return value of debugfs_create_bool() scsi: snic: debugfs: remove local storage of debugfs files b43: don't save dentries for debugfs b43legacy: don't save dentries for debugfs ...
2021-06-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Trivial conflicts in net/can/isotp.c and tools/testing/selftests/net/mptcp/mptcp_connect.sh scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c to include/linux/ptp_clock_kernel.h in -next so re-apply the fix there. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-17driver core: add a helper to setup both the of_node and fwnode of a deviceIoana Ciornei
There are many places where both the fwnode_handle and the of_node of a device need to be populated. Add a function which does both so that we have consistency. Suggested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-31Merge 5.13-rc4 into usb-nextGreg Kroah-Hartman
We need the usb/thunderbolt fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-31Merge 5.13-rc4 into driver-core-nextGreg Kroah-Hartman
We need the driver core fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-27driver core: Move the "removable" attribute from USB to coreRajat Jain
Move the "removable" attribute from USB to core in order to allow it to be supported by other subsystem / buses. Individual buses that want to support this attribute can populate the removable property of the device while enumerating it with the 3 possible values - - "unknown" - "fixed" - "removable" Leaving the field unchanged (i.e. "not supported") would mean that the attribute would not show up in sysfs for that device. The UAPI (location, symantics etc) for the attribute remains unchanged. Move the "removable" attribute from USB to the device core so it can be used by other subsystems / buses. By default, devices do not have a "removable" attribute in sysfs. If a subsystem or bus driver wants to support a "removable" attribute, it should call device_set_removable() before calling device_register() or device_add(), e.g.: device_set_removable(dev, DEVICE_REMOVABLE); device_register(dev); The possible values and the resulting sysfs attribute contents are: DEVICE_REMOVABLE_UNKNOWN -> "unknown" DEVICE_REMOVABLE -> "removable" DEVICE_FIXED -> "fixed" Convert the USB "removable" attribute to use this new device core functionality. There should be no user-visible change in the location or semantics of attribute for USB devices. Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Rajat Jain <rajatja@google.com> Link: https://lore.kernel.org/r/20210524171812.18095-1-rajatja@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21drivers: base: Reduce device link removal code duplicationRafael J. Wysocki
Reduce device link removal code duplication between the cases when SRCU is enabled and when it is disabled by moving the only differing piece of it (which is the removal of the link from the consumer and supplier lists) into a separate wrapper function (defined differently for each of the cases in question). No intentional functional impact. Reviewed-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/4326215.LvFx2qVVIh@kreacher Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21drivers: base: Fix device link removalRafael J. Wysocki
When device_link_free() drops references to the supplier and consumer devices of the device link going away and the reference being dropped turns out to be the last one for any of those device objects, its ->release callback will be invoked and it may sleep which goes against the SRCU callback execution requirements. To address this issue, make the device link removal code carry out the device_link_free() actions preceded by SRCU synchronization from a separate work item (the "long" workqueue is used for that, because it does not matter when the device link memory is released and it may take time to get to that point) instead of using SRCU callbacks. While at it, make the code work analogously when SRCU is not enabled to reduce the differences between the SRCU and non-SRCU cases. Fixes: 843e600b8a2b ("driver core: Fix sleeping in invalid context during device link deletion") Cc: stable <stable@vger.kernel.org> Reported-by: chenxiang (M) <chenxiang66@hisilicon.com> Tested-by: chenxiang (M) <chenxiang66@hisilicon.com> Reviewed-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/5722787.lOV4Wx5bFT@kreacher Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-17Merge 5.13-rc2 into driver-core-nextGreg Kroah-Hartman
We need the driver core fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14driver core: replace open-coded device_lock_assert()Julian Wiedmann
Using the right wrapper makes it easier to associate this assert statement with the device_[un]lock() helpers. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Link: https://lore.kernel.org/r/20210512141054.2180373-1-jwi@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-10usb: typec: tcpm: Don't block probing of consumers of "connector" nodesSaravana Kannan
fw_devlink expects DT device nodes with "compatible" property to have struct devices created for them. Since the connector node might not be populated as a device, mark it as such so that fw_devlink knows not to wait on this fwnode being populated as a struct device. Without this patch, USB functionality can be broken on some boards. Fixes: f7514a663016 ("of: property: fw_devlink: Add support for remote-endpoint") Reported-by: John Stultz <john.stultz@linaro.org> Tested-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210506004423.345199-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-05driver core: Improve fw_devlink & deferred_probe_timeout interactionSaravana Kannan
deferred_probe_timeout kernel commandline parameter allows probing of consumer devices if the supplier devices don't have any drivers. fw_devlink=on will indefintely block probe() calls on a device if all its suppliers haven't probed successfully. This completely skips calls to driver_deferred_probe_check_state() since that's only called when a .probe() function calls framework APIs. So fw_devlink=on breaks deferred_probe_timeout. deferred_probe_timeout in its current state also ignores a lot of information that's now available to the kernel. It assumes all suppliers that haven't probed when the timer expires (or when initcalls are done on a static kernel) will never probe and fails any calls to acquire resources from these unprobed suppliers. However, this assumption by deferred_probe_timeout isn't true under many conditions. For example: - If the consumer happens to be before the supplier in the deferred probe list. - If the supplier itself is waiting on its supplier to probe. This patch fixes both these issues by relaxing device links between devices only if the supplier doesn't have any driver that could match with (NOT bound to) the supplier device. This way, we only fail attempts to acquire resources from suppliers that truly don't have any driver vs suppliers that just happen to not have probed yet. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210402040342.2944858-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-02driver core: remove kernel-doc warningsPierre-Louis Bossart
remove make W=1 warning: drivers/base/core.c:1670: warning: Function parameter or member 'flags' not described in 'fw_devlink_create_devlink' drivers/base/core.c:1670: warning: Function parameter or member 'con' not described in 'fw_devlink_create_devlink' drivers/base/core.c:1670: warning: Function parameter or member 'sup_handle' not described in 'fw_devlink_create_devlink' drivers/base/core.c:1670: warning: Function parameter or member 'flags' not described in 'fw_devlink_create_devlink' drivers/base/core.c:1763: warning: Function parameter or member 'dev' not described in '__fw_devlink_link_to_consumers' drivers/base/core.c:1844: warning: Function parameter or member 'dev' not described in '__fw_devlink_link_to_suppliers' drivers/base/core.c:1844: warning: Function parameter or member 'fwnode' not described in '__fw_devlink_link_to_suppliers' Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20210331232614.304591-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23Revert "Revert "driver core: Set fw_devlink=on by default""Saravana Kannan
This reverts commit 3e4c982f1ce75faf5314477b8da296d2d00919df. Since all reported issues due to fw_devlink=on should be addressed by this series, revert the revert. fw_devlink=on Take II. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210302211133.2244281-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23driver core: Update device link status properly for device_bind_driver()Saravana Kannan
Device link status was not getting updated correctly when device_bind_driver() is called on a device. This causes a warning[1]. Fix this by updating device links that can be updated and dropping device links that can't be updated to a sensible state. [1] - https://lore.kernel.org/lkml/56f7d032-ba5a-a8c7-23de-2969d98c527e@nvidia.com/ Tested-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210302211133.2244281-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-24Merge tag 'driver-core-5.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core / debugfs update from Greg KH: "Here is the "big" driver core and debugfs update for 5.12-rc1 This set of driver core patches caused a bunch of problems in linux-next for the past few weeks, when Saravana tried to set fw_devlink=on as the default functionality. This caused a number of systems to stop booting, and lots of bugs were fixed in this area for almost all of the reported systems, but this option is not ready to be turned on just yet for the default operation based on this testing, so I've reverted that change at the very end so we don't have to worry about regressions in 5.12 We will try to turn this on for 5.13 if testing goes better over the next few months. Other than the fixes caused by the fw_devlink testing in here, there's not much more: - debugfs fixes for invalid input into debugfs_lookup() - kerneldoc cleanups - warn message if platform drivers return an error on their remove callback (a futile effort, but good to catch). All of these have been in linux-next for a while now, and the regressions have gone away with the revert of the fw_devlink change" * tag 'driver-core-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (35 commits) Revert "driver core: Set fw_devlink=on by default" of: property: fw_devlink: Ignore interrupts property for some configs debugfs: do not attempt to create a new file before the filesystem is initalized debugfs: be more robust at handling improper input in debugfs_lookup() driver core: auxiliary bus: Fix calling stage for auxiliary bus init of: irq: Fix the return value for of_irq_parse_one() stub of: irq: make a stub for of_irq_parse_one() clk: Mark fwnodes when their clock provider is added/removed PM: domains: Mark fwnodes when their powerdomain is added/removed irqdomain: Mark fwnodes when their irqdomain is added/removed driver core: fw_devlink: Handle suppliers that don't use driver core of: property: Add fw_devlink support for optional properties driver core: Add fw_devlink.strict kernel param of: property: Don't add links to absent suppliers driver core: fw_devlink: Detect supplier devices that will never be added driver core: platform: Emit a warning if a remove callback returned non-zero of: property: Fix fw_devlink handling of interrupts/interrupts-extended gpiolib: Don't probe gpio_device if it's not the primary device device.h: Remove bogus "the" in kerneldoc gpiolib: Bind gpio_device to a driver to enable fw_devlink=on by default ...
2021-02-21Merge tag 'mips_5.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS updates from Thomas Bogendoerfer: - added support for Nintendo N64 - added support for Realtek RTL83XX SoCs - kaslr support for Loongson64 - first steps to get rid of set_fs() - DMA runtime coherent/non-coherent selection cleanup - cleanups and fixes * tag 'mips_5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (98 commits) Revert "MIPS: Add basic support for ptrace single step" vmlinux.lds.h: catch more UBSAN symbols into .data MIPS: kernel: Drop kgdb_call_nmi_hook MAINTAINERS: Add git tree for KVM/mips MIPS: Use common way to parse elfcorehdr MIPS: Simplify EVA cache handling Revert "MIPS: kernel: {ftrace,kgdb}: Set correct address limit for cache flushes" MIPS: remove CONFIG_DMA_PERDEV_COHERENT MIPS: remove CONFIG_DMA_MAYBE_COHERENT driver core: lift dma_default_coherent into common code MIPS: refactor the runtime coherent vs noncoherent DMA indicators MIPS/alchemy: factor out the DMA coherent setup MIPS/malta: simplify plat_setup_iocoherency MIPS: Add basic support for ptrace single step MAINTAINERS: replace non-matching patterns for loongson{2,3} MIPS: Make check condition for SDBBP consistent with EJTAG spec mips: Replace lkml.org links with lore Revert "MIPS: microMIPS: Fix the judgment of mm_jr16_op and mm_jalr_op" MIPS: crash_dump.c: Simplify copy_oldmem_page() Revert "mips: Manually call fdt_init_reserved_mem() method" ...
2021-02-19Revert "driver core: Set fw_devlink=on by default"Greg Kroah-Hartman
This reverts commit e590474768f1cc04852190b61dec692411b22e2a. While things are _almost_ there and working for almost all systems, there are still reported regressions happening, so let's revert this default for 5.12. We can bring it back in linux-next after 5.12-rc1 is out to get more testing and hopefully solve the remaining different subsystem and driver issues that people are running into. Cc: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210219074549.1506936-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13driver core: lift dma_default_coherent into common codeChristoph Hellwig
Lift the dma_default_coherent variable from the mips architecture code to the driver core. This allows an architecture to sdefault all device to be DMA coherent at run time, even if the kernel is build with support for DMA noncoherent device. By allowing device_initialize to set the ->dma_coherent field to this default the amount of arch hooks required for this behavior can be greatly reduced. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-02-09driver core: fw_devlink: Handle suppliers that don't use driver coreSaravana Kannan
Device links only work between devices that use the driver core to match and bind a driver to a device. So, add an API for frameworks to let the driver core know that a fwnode has been initialized by a driver without using the driver core. Then use this information to make sure that fw_devlink doesn't make the consumers wait indefinitely on suppliers that'll never bind to a driver. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210205222644.2357303-6-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09driver core: Add fw_devlink.strict kernel paramSaravana Kannan
This param allows forcing all dependencies to be treated as mandatory. This will be useful for boards in which all optional dependencies like IOMMUs and DMAs need to be treated as mandatory dependencies. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210205222644.2357303-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09driver core: fw_devlink: Detect supplier devices that will never be addedSaravana Kannan
During the initial parsing of firmware by fw_devlink, fw_devlink might infer that some supplier firmware nodes would get populated as devices. But the inference is not always correct. This patch tries to logically detect and fix such mistakes as boot progresses or more devices probe. fw_devlink makes a fundamental assumption that once a device binds to a driver, it will populate (i.e: add as struct devices) all the child firmware nodes that could be populated as devices (if they aren't populated already). So, whenever a device probes, we check all its child firmware nodes. If a child firmware node has a corresponding device populated, we don't modify the child node or its descendants. However, if a child firmware node has not been populated as a device, we delete all the fwnode links where the child node or its descendants are suppliers. This ensures that no other device is blocked on a firmware node that will never be populated as a device. We also mark such fwnodes as NOT_DEVICE, so that no new fwnode links are created with these nodes as suppliers. Fixes: e590474768f1 ("driver core: Set fw_devlink=on by default") Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210205222644.2357303-2-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-25Merge 5.11-rc5 into driver-core-nextGreg Kroah-Hartman
We need the fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-24Merge tag 'driver-core-5.11-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fixes from Greg KH: "Here are some small driver core fixes for 5.11-rc5 that resolve some reported problems: - revert of a -rc1 patch that was causing problems with some machines - device link device name collision problem fix (busses only have to name devices unique to their bus, not unique to all busses) - kernfs splice bugfixes to resolve firmware loading problems for Qualcomm systems. - other tiny driver core fixes for minor issues reported. All of these have been in linux-next with no reported problems" * tag 'driver-core-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: driver core: Fix device link device name collision driver core: Extend device_is_dependent() kernfs: wire up ->splice_read and ->splice_write kernfs: implement ->write_iter kernfs: implement ->read_iter Revert "driver core: Reorder devices on successful probe" Driver core: platform: Add extra error check in devm_platform_get_irqs_affinity() drivers core: Free dma_range_map when driver probe failed
2021-01-21driver core: Fix device link device name collisionSaravana Kannan
The device link device's name was of the form: <supplier-dev-name>--<consumer-dev-name> This can cause name collision as reported here [1] as device names are not globally unique. Since device names have to be unique within the bus/class, add the bus/class name as a prefix to the device names used to construct the device link device name. So the devuce link device's name will be of the form: <supplier-bus-name>:<supplier-dev-name>--<consumer-bus-name>:<consumer-dev-name> [1] - https://lore.kernel.org/lkml/20201229033440.32142-1-michael@walle.cc/ Fixes: 287905e68dd2 ("driver core: Expose device link details in sysfs") Cc: stable@vger.kernel.org Reported-by: Michael Walle <michael@walle.cc> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210110175408.1465657-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-21driver core: Extend device_is_dependent()Rafael J. Wysocki
If the device passed as the target (second argument) to device_is_dependent() is not completely registered (that is, it has been initialized, but not added yet), but the parent pointer of it is set, it may be missing from the list of the parent's children and device_for_each_child() called by device_is_dependent() cannot be relied on to catch that dependency. For this reason, modify device_is_dependent() to check the ancestors of the target device by following its parent pointer in addition to the device_for_each_child() walk. Fixes: 9ed9895370ae ("driver core: Functional dependencies tracking support") Reported-by: Stephan Gerhold <stephan@gerhold.net> Tested-by: Stephan Gerhold <stephan@gerhold.net> Reviewed-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/17705994.d592GUb2YH@kreacher Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-12Revert "drivers: core: Detach device from power domain on shutdown"Greg Kroah-Hartman
This reverts commit 0fab972eef49ef8d30eb91d6bd98861122d083d1 as it is reported by users to cause problems. Reported-by: Dmitry Osipenko <digetx@gmail.com> Fixes: 0fab972eef49 ("drivers: core: Detach device from power domain on shutdown") Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Furquan Shaikh <furquan@google.com> Link: https://lore.kernel.org/r/CAJZ5v0jhniqG43F6hCqXdxQiQZRc67GdkdP0BXcRut=P7k7BVQ@mail.gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-08drivers: core: Detach device from power domain on shutdownFurquan Shaikh
When the system is powered off or rebooted, devices are not detached from their PM domain. This results in ACPI PM not being invoked and hence PowerResouce _OFF method not being invoked for any of the devices. Because the ACPI power resources are not turned off in case of poweroff and reboot, it violates the power sequencing requirements which impacts the reliability of the devices over the lifetime of the platform. This is currently observed on all Chromebooks using ACPI. In order to solve the above problem, this change detaches a device from its PM domain whenever it is shutdown. This action is basically analogous to ->remove() from driver model perspective. Detaching the device from its PM domain ensures that the ACPI PM gets a chance to turn off the power resources for the device thus complying with its power sequencing requirements. Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Furquan Shaikh <furquan@google.com> Link: https://lore.kernel.org/r/20201201213019.1558738-1-furquan@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07driver core: Set fw_devlink=on by defaultSaravana Kannan
Cyclic dependencies in some firmware was one of the last remaining reasons fw_devlink=on couldn't be set by default. Now that cyclic dependencies don't block probing, set fw_devlink=on by default. Setting fw_devlink=on by default brings a bunch of benefits (currently, only for systems with device tree firmware): * Significantly cuts down deferred probes. * Device probe is effectively attempted in graph order. * Makes it much easier to load drivers as modules without having to worry about functional dependencies between modules (depmod is still needed for symbol dependencies). If this patch prevents some devices from probing, it's very likely due to the system having one or more device drivers that "probe"/set up a device (DT node with compatible property) without creating a struct device for it. If we hit such cases, the device drivers need to be fixed so that they populate struct devices and probe them like normal device drivers so that the driver core is aware of the devices and their status. See [1] for an example of such a case. [1] - https://lore.kernel.org/lkml/CAGETcx9PiX==mLxB9PO8Myyk6u2vhPVwTMsA5NkD-ywH5xhusw@mail.gmail.com/ Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201218031703.3053753-6-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07driver core: fw_devlink_relax_cycle() can be statickernel test robot
Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/r/20201218063934.GA66003@e60698be8304 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07driver core: Handle cycles in device links created by fw_devlinkSaravana Kannan
Sometimes, firmware can have cyclic dependencies between devices. But one or more of those dependencies in the cycle are false dependencies that don't affect the probing of the device. fw_devlink can detect some of these false dependencies using logic. But when it can't, we don't want to block probing of the devices in this cyclic dependency. So, instead of using normal device links for the devices in this cycle, we need to switch to SYNC_STATE_ONLY device links between these devices. This is so that sync_state() callback correctness is still maintained while we allow these device to probe. This is functionally similar to switching to fw_devlink=permissive just for the devices in the cycle. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201218031703.3053753-5-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07driver core: Have fw_devlink use DL_FLAG_INFERREDSaravana Kannan
This will be useful in identifying device links created only due to fw_devlink when we need to break cyclic dependencies due to fw_devlink. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201218031703.3053753-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07driver core: Add device link support for INFERRED flagSaravana Kannan
This flag can never be added to a device link that already exists and doesn't have the flag set. It can only be added when a device link is created for the first time or it can be maintained if the device link already has the it set. This flag will be used for marking device links created ONLY by inferring dependencies from data and NOT from explicit action by device drivers/frameworks. This will be useful in the future when we need to deal with cycles in dependencies inferred from firmware. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201218031703.3053753-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07driver core: Add debug logs for device link related probe deferralsSaravana Kannan
There's insufficient logging when device links or fw_devlink (waiting to create device links) cause probe deferrals. This makes it hard to debug devices not getting probed. So, add debug logs to make it easy to debug. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201218031703.3053753-2-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07device property: add description of fwnode casesBard Liao
There are only four valid fwnode cases which are - primary --> secondary --> -ENODEV - primary --> NULL - secondary --> -ENODEV - NULL dev->fwnode should be converted between the 4 cases above no matter how/when set_primary_fwnode() and set_secondary_fwnode() are called. Describe it in the code so people will keep it in mind. Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> [ rjw: Comment edit ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-07Revert "device property: Keep secondary firmware node secondary by type"Bard Liao
While commit d5dcce0c414f ("device property: Keep secondary firmware node secondary by type") describes everything correct in its commit message, the change it made does the opposite and original commit c15e1bdda436 ("device property: Fix the secondary firmware node handling in set_primary_fwnode()") was fully correct. Revert the former one here and improve documentation in the next patch. Fixes: d5dcce0c414f ("device property: Keep secondary firmware node secondary by type") Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: 5.10+ <stable@vger.kernel.org> # 5.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-09driver core: Fix a couple of typosThierry Reding
These were just some minor typos that have crept in recently and are easily fixed. Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Link: https://lore.kernel.org/r/20201127104630.1839171-1-thierry.reding@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver core: Delete pointless parameter in fwnode_operations.add_linksSaravana Kannan
The struct device input to add_links() is not used for anything. So delete it. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-18-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver core: Refactor fw_devlink featureSaravana Kannan
The current implementation of fw_devlink is very inefficient because it tries to get away without creating fwnode links in the name of saving memory usage. Past attempts to optimize runtime at the cost of memory usage were blocked with request for data showing that the optimization made significant improvement for real world scenarios. We have those scenarios now. There have been several reports of boot time increase in the order of seconds in this thread [1]. Several OEMs and SoC manufacturers have also privately reported significant (350-400ms) increase in boot time due to all the parsing done by fw_devlink. So this patch uses all the setup done by the previous patches in this series to refactor fw_devlink to be more efficient. Most of the code has been moved out of firmware specific (DT mostly) code into driver core. This brings the following benefits: - Instead of parsing the device tree multiple times during bootup, fw_devlink parses each fwnode node/property only once and creates fwnode links. The rest of the fw_devlink code then just looks at these fwnode links to do rest of the work. - Makes it much easier to debug probe issue due to fw_devlink in the future. fw_devlink=on blocks the probing of devices if they depend on a device that hasn't been added yet. With this refactor, it'll be very easy to tell what that device is because we now have a reference to the fwnode of the device. - Much easier to add fw_devlink support to ACPI and other firmware types. A refactor to move the common bits from DT specific code to driver core was in my TODO list as a prerequisite to adding ACPI support to fw_devlink. This series gets that done. [1] - https://lore.kernel.org/linux-omap/ea02f57e-871d-cd16-4418-c1da4bbc4696@ti.com/ Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-17-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver core: Use device's fwnode to check if it is waiting for suppliersSaravana Kannan
To check if a device is still waiting for its supplier devices to be added, we used to check if the devices is in a global waiting_for_suppliers list. Since the global list will be deleted in subsequent patches, this patch stops using this check. Instead, this patch uses a more device specific check. It checks if the device's fwnode has any fwnode links that haven't been converted to device links yet. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-14-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver core: Add fw_devlink_parse_fwtree()Saravana Kannan
This function is a wrapper around fwnode_operations.add_links(). This function parses each node in a fwnode tree and create fwnode links for each of those nodes. The information for creating the fwnode links (the supplier and consumer fwnode) is obtained by parsing the properties in each of the fwnodes. This function also ensures that no fwnode is parsed more than once by marking the fwnodes as parsed. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-13-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver core: Allow only unprobed consumers for SYNC_STATE_ONLY device linksSaravana Kannan
SYNC_STATE_ONLY device links only affect the behavior of sync_state() callbacks. Specifically, they prevent sync_state() only callbacks from being called on a device if one or more of its consumers haven't probed. So, creating a SYNC_STATE_ONLY device link from an already probed consumer is useless. So, don't allow creating such device links. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-10-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver core: Add fwnode link supportSaravana Kannan
Add support for creating supplier-consumer links between fwnodes. It is intended for internal use the driver core and generic firmware support code (eg. Device Tree, ACPI), so it is simple by design and the API provided is limited. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-9-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09Revert "driver core: fw_devlink: Add support for batching fwnode parsing"Saravana Kannan
This reverts commit 716a7a25969003d82ab738179c3f1068a120ed11. The fw_devlink_pause/resume() APIs added by the commit being reverted were a first cut attempt at optimizing boot time. But these APIs don't fully solve the problem and are very fragile (can only be used for the top level devices being added). This series replaces them with a much better optimization that works for all device additions and also has the benefit of reducing the complexity of the firmware (DT, EFI) specific code and abstracting out common code to driver core. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-7-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09Revert "driver core: Don't do deferred probe in parallel with kernel_init ↵Saravana Kannan
thread" This reverts commit cec72f3efc6272420c2c2c699607f03d09b93e41. Commit cec72f3efc62 ("driver core: Don't do deferred probe in parallel with kernel_init thread") was fixing a commit 716a7a259690 ("driver core: fw_devlink: Add support for batching fwnode parsing"). Since the commit being fixed itself is going to be reverted, the fix can also be reverted. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09Revert "driver core: Rename dev_links_info.defer_sync to defer_hook"Saravana Kannan
This reverts commit ec7bd78498f29680f536451fbdf9464e851273ed. This field rename was done to reuse defer_syc list head for multiple lists. That's not needed anymore and this list head will only be used for defer sync. So revert this patch to avoid conflicts with the other reverts coming after this. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09Revert "driver core: Avoid deferred probe due to fw_devlink_pause/resume()"Saravana Kannan
This reverts commit 2451e746478a6a6e981cfa66b62b791ca93b90c8. fw_devlink_pause/resume() was an incomplete attempt at boot time optimization. That's going to get replaced by a much better optimization at the end of the series. Since fw_devlink_pause/resume() is going away, changes made for that can also go away. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-2-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09driver: core: Fix list corruption after device_del()Takashi Iwai
The device_links_purge() function (called from device_del()) tries to remove the links.needs_suppliers list entry, but it's using list_del(), hence it doesn't initialize after the removal. This is OK for normal cases where device_del() is called via device_destroy(). However, it's not guaranteed that the device object will be really deleted soon after device_del(). In a minor case like HD-audio codec reconfiguration that re-initializes the device after device_del(), it may lead to a crash by the corrupted list entry. As a simple fix, replace list_del() with list_del_init() in order to make the list intact after the device_del() call. Fixes: e2ae9bcc4aaa ("driver core: Add support for linking devices during device addition") Cc: <stable@vger.kernel.org> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Link: https://lore.kernel.org/r/20201208190326.27531-1-tiwai@suse.de Cc: Saravana Kannan <saravanak@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-09driver core: Fix lockdep warning on wfs_lockSaravana Kannan
There's a potential deadlock with the following cycle: wfs_lock --> device_links_lock --> kn->count Fix this by simply dropping the lock around a list_empty() check that's just exported to a sysfs file. The sysfs file output is an instantaneous check anyway and the lock doesn't really add any protection. Lockdep log: [ 48.808132] [ 48.808132] the existing dependency chain (in reverse order) is: [ 48.809069] [ 48.809069] -> #2 (kn->count){++++}: [ 48.809707] __kernfs_remove.llvm.7860393000964815146+0x2d4/0x460 [ 48.810537] kernfs_remove_by_name_ns+0x54/0x9c [ 48.811171] sysfs_remove_file_ns+0x18/0x24 [ 48.811762] device_del+0x2b8/0x5a8 [ 48.812269] __device_link_del+0x98/0xb8 [ 48.812829] device_links_driver_bound+0x210/0x2d8 [ 48.813496] driver_bound+0x44/0xf8 [ 48.814000] really_probe+0x340/0x6e0 [ 48.814526] driver_probe_device+0xb8/0x100 [ 48.815117] device_driver_attach+0x78/0xb8 [ 48.815708] __driver_attach+0xe0/0x194 [ 48.816255] bus_for_each_dev+0xa8/0x11c [ 48.816816] driver_attach+0x24/0x30 [ 48.817331] bus_add_driver+0x100/0x1e0 [ 48.817880] driver_register+0x78/0x114 [ 48.818427] __platform_driver_register+0x44/0x50 [ 48.819089] 0xffffffdbb3227038 [ 48.819551] do_one_initcall+0xd8/0x1e0 [ 48.820099] do_init_module+0xd8/0x298 [ 48.820636] load_module+0x3afc/0x44c8 [ 48.821173] __arm64_sys_finit_module+0xbc/0xf0 [ 48.821807] el0_svc_common+0xbc/0x1d0 [ 48.822344] el0_svc_handler+0x74/0x98 [ 48.822882] el0_svc+0x8/0xc [ 48.823310] [ 48.823310] -> #1 (device_links_lock){+.+.}: [ 48.824036] __mutex_lock_common+0xe0/0xe44 [ 48.824626] mutex_lock_nested+0x28/0x34 [ 48.825185] device_link_add+0xd4/0x4ec [ 48.825734] of_link_to_suppliers+0x158/0x204 [ 48.826347] of_fwnode_add_links+0x50/0x64 [ 48.826928] device_link_add_missing_supplier_links+0x90/0x11c [ 48.827725] fw_devlink_resume+0x58/0x130 [ 48.828296] of_platform_default_populate_init+0xb4/0xd0 [ 48.829030] do_one_initcall+0xd8/0x1e0 [ 48.829578] do_initcall_level+0xb8/0xcc [ 48.830137] do_basic_setup+0x60/0x7c [ 48.830662] kernel_init_freeable+0x128/0x1ac [ 48.831275] kernel_init+0x18/0x29c [ 48.831781] ret_from_fork+0x10/0x18 [ 48.832297] [ 48.832297] -> #0 (wfs_lock){+.+.}: [ 48.832922] __lock_acquire+0xe04/0x2e20 [ 48.833480] lock_acquire+0xbc/0xec [ 48.833984] __mutex_lock_common+0xe0/0xe44 [ 48.834577] mutex_lock_nested+0x28/0x34 [ 48.835136] waiting_for_supplier_show+0x3c/0x98 [ 48.835781] dev_attr_show+0x48/0xb4 [ 48.836295] sysfs_kf_seq_show+0xe8/0x184 [ 48.836864] kernfs_seq_show+0x48/0x8c [ 48.837401] seq_read+0x1c8/0x600 [ 48.837884] kernfs_fop_read+0x68/0x204 [ 48.838431] __vfs_read+0x60/0x214 [ 48.838925] vfs_read+0xbc/0x15c [ 48.839397] ksys_read+0x78/0xe4 [ 48.839869] __arm64_sys_read+0x1c/0x28 [ 48.840416] el0_svc_common+0xbc/0x1d0 [ 48.840953] el0_svc_handler+0x74/0x98 [ 48.841490] el0_svc+0x8/0xc [ 48.841917] [ 48.841917] other info that might help us debug this: [ 48.841917] [ 48.842920] Chain exists of: [ 48.842920] wfs_lock --> device_links_lock --> kn->count [ 48.842920] [ 48.844152] Possible unsafe locking scenario: [ 48.844152] [ 48.844895] CPU0 CPU1 [ 48.845463] ---- ---- [ 48.846032] lock(kn->count); [ 48.846417] lock(device_links_lock); [ 48.847203] lock(kn->count); [ 48.847902] lock(wfs_lock); [ 48.848276] [ 48.848276] *** DEADLOCK *** Reported-by: Cheng-Jui.Wang@mediatek.com Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201104205431.3795207-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-02PM: runtime: Drop runtime PM references to supplier on link removalRafael J. Wysocki
While removing a device link, drop the supplier device's runtime PM usage counter as many times as needed to drop all of the runtime PM references to it from the consumer in addition to dropping the consumer's link count. Fixes: baa8809f6097 ("PM / runtime: Optimize the use of device links") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Tested-by: Xiang Chen <chenxiang66@hisilicon.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>