kernel/git/stable/linux.git/drivers/acpi/scan.c, branch linux-5.7.y

ACPI: PM: Avoid using power resources if there are none for D0

2020-06-17T14:42:53+00:00

commit 956ad9d98b73f59e442cc119c98ba1e04e94fe6d upstream. As recently reported, some platforms provide a list of power resources for device power state D3hot, through the _PR3 object, but they do not provide a list of power resources for device power state D0. Among other things, this causes acpi_device_get_power() to return D3hot as the current state of the device in question if all of the D3hot power resources are "on", because it sees the power_resources flag set and calls acpi_power_get_inferred_state() which finds that D3hot is the shallowest power state with all of the associated power resources turned "on", so that's what it returns. Moreover, that value takes precedence over the acpi_dev_pm_explicit_get() return value, because it means a deeper power state. The device may very well be in D0 physically at that point, however. Moreover, the presence of _PR3 without _PR0 for a given device means that only one D3-level power state can be supported by it. Namely, because there are no power resources to turn "off" when transitioning the device from D0 into D3cold (which should be supported since _PR3 is present), the evaluation of _PS3 should be sufficient to put it straight into D3cold, but this means that the effect of turning "on" the _PR3 power resources is unclear, so it is better to avoid doing that altogether. Consequently, there is no practical way do distinguish D3cold from D3hot for the device in question and the power states of it can be labeled so that D3hot is the deepest supported one (and Linux assumes that putting a device into D3hot via ACPI may cause power to be removed from it anyway, for legacy reasons). To work around the problem described above modify the ACPI enumeration of devices so that power resources are only used for device power management if the list of D0 power resources is not empty and make it mart D3cold as supported only if that is the case and the D3hot list of power resources is not empty too. Fixes: ef85bdbec444 ("ACPI / scan: Consolidate extraction of power resources lists") Link: https://bugzilla.kernel.org/show_bug.cgi?id=205057 Link: https://lore.kernel.org/linux-acpi/20200603194659.185757-1-hdegoede@redhat.com/ Reported-by: Hans de Goede Tested-by: Hans de Goede Tested-by: youling257@gmail.com Cc: 3.10+ # 3.10+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Hans de Goede Signed-off-by: Greg Kroah-Hartman

treewide: remove redundant IS_ERR() before error code check

2020-02-04T03:05:27+00:00

'PTR_ERR(p) == -E*' is a stronger condition than IS_ERR(p). Hence, IS_ERR(p) is unneeded. The semantic patch that generates this commit is as follows: // @@ expression ptr; constant error_code; @@ -IS_ERR(ptr) && (PTR_ERR(ptr) == - error_code) +PTR_ERR(ptr) == - error_code // Link: http://lkml.kernel.org/r/20200106045833.1725-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada Cc: Julia Lawall Acked-by: Stephen Boyd [drivers/clk/clk.c] Acked-by: Bartosz Golaszewski [GPIO] Acked-by: Wolfram Sang [drivers/i2c] Acked-by: Rafael J. Wysocki [acpi/scan.c] Acked-by: Rob Herring Cc: Eric Biggers Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ACPI: platform: Unregister stale platform devices

2019-10-17T21:48:39+00:00

When commit 68bdb6773289 ("ACPI: add support for ACPI reconfiguration notifiers") introduced reconfiguration notifiers, it missed the point that the ACPI table, which might be loaded and then unloaded via ConfigFS, could contain devices that were not enumerated by their parents. In such cases, the stale platform device is dangling in the system while the rest of the devices from the same table are already gone. Introduce acpi_platform_device_remove_notify() notifier that, in similar way to I²C or SPI buses, unregisters the platform devices on table removal event. Fixes: 68bdb6773289 ("ACPI: add support for ACPI reconfiguration notifiers") Depends-on: 00500147cbd3 ("drivers: Introduce device lookup variants by ACPI_COMPANION device") Signed-off-by: Andy Shevchenko [ rjw: Changelog & function rename ] Signed-off-by: Rafael J. Wysocki

drivers/acpi/scan.c: document why we don't need the device_hotplug_lock

2019-08-03T14:02:01+00:00

Let's document why the lock is not needed in acpi_scan_init(), right now this is not really obvious. [akpm@linux-foundation.org: fix tpyo] Link: http://lkml.kernel.org/r/20190731135306.31524-1-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Rafael J. Wysocki Cc: Oscar Salvador Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45+00:00

Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2019-05-07T20:01:40+00:00

Pull driver core/kobject updates from Greg KH: "Here is the "big" set of driver core patches for 5.2-rc1 There are a number of ACPI patches in here as well, as Rafael said they should go through this tree due to the driver core changes they required. They have all been acked by the ACPI developers. There are also a number of small subsystem-specific changes in here, due to some changes to the kobject core code. Those too have all been acked by the various subsystem maintainers. As for content, it's pretty boring outside of the ACPI changes: - spdx cleanups - kobject documentation updates - default attribute groups for kobjects - other minor kobject/driver core fixes All have been in linux-next for a while with no reported issues" * tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (47 commits) kobject: clean up the kobject add documentation a bit more kobject: Fix kernel-doc comment first line kobject: Remove docstring reference to kset firmware_loader: Fix a typo ("syfs" -> "sysfs") kobject: fix dereference before null check on kobj Revert "driver core: platform: Fix the usage of platform device name(pdev->name)" init/config: Do not select BUILD_BIN2C for IKCONFIG Provide in-kernel headers to make extending kernel easier kobject: Improve doc clarity kobject_init_and_add() kobject: Improve docs for kobject_add/del driver core: platform: Fix the usage of platform device name(pdev->name) livepatch: Replace klp_ktype_patch's default_attrs with groups cpufreq: schedutil: Replace default_attrs field with groups padata: Replace padata_attr_type default_attrs field with groups irqdesc: Replace irq_kobj_type's default_attrs field with groups net-sysfs: Replace ktype default_attrs field with groups block: Replace all ktype default_attrs with groups samples/kobject: Replace foo_ktype's default_attrs field with groups kobject: Add support for default attribute groups to kobj_type driver core: Postpone DMA tear-down until after devres release for probe failure ...

Merge branches 'acpi-scan', 'acpi-tables', 'acpi-misc' and 'acpi-pm'

2019-05-06T08:49:39+00:00

* acpi-scan: ACPI / scan: Add labels for PNP button devices ACPI / scan: Simplify acpi_bus_extract_wakeup_device_power_package() * acpi-tables: ACPI / tables: Clean up whitespace * acpi-misc: ACPI / DPTF: Use dev_get_drvdata() ACPI: event: replace strcpy() by strscpy() ACPI: Fix comment typos * acpi-pm: ACPI: PM: Print debug messages when enabling GPEs for wakeup

ACPICA: Rename nameseg compare macro for clarity

2019-04-09T08:08:28+00:00

ACPICA commit 92ec0935f27e217dff0b176fca02c2ec3d782bb5 ACPI_COMPARE_NAME changed to ACPI_COMPARE_NAMESEG This clarifies (1) this is a compare on 4-byte namesegs, not a generic compare. Improves understanding of the code. Link: https://github.com/acpica/acpica/commit/92ec0935 Signed-off-by: Bob Moore Signed-off-by: Erik Schmauss Signed-off-by: Rafael J. Wysocki

acpi: Create subtable parsing infrastructure

2019-04-04T16:41:12+00:00

Parsing entries in an ACPI table had assumed a generic header structure. There is no standard ACPI header, though, so less common layouts with different field sizes required custom parsers to go through their subtable entry list. Create the infrastructure for adding different table types so parsing the entries array may be more reused for all ACPI system tables and the common code doesn't need to be duplicated. Reviewed-by: Rafael J. Wysocki Acked-by: Jonathan Cameron Tested-by: Jonathan Cameron Signed-off-by: Keith Busch Tested-by: Brice Goglin Signed-off-by: Greg Kroah-Hartman

ACPI / scan: Add labels for PNP button devices

2019-03-26T21:36:46+00:00

Subsequent code treats button_device_ids[] entries differently, and it's hard to follow without a hint as to which is which. Add comments to identify the power button, lid, and sleep button devices. The "PNP" prefix is owned by Microsoft, so they distribute the canonical list of "PNP" IDs. Link: https://uefi.org/PNP_ACPI_Registry Link: https://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/devids.txt Signed-off-by: Bjorn Helgaas Signed-off-by: Rafael J. Wysocki