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2018-03-23Documentation: gpio: Move driver documentation to driver-apiJonathan Neuschäfer2-0/+430
Move gpio/driver.txt to driver-api/gpio/driver.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: gpio: Move introduction to driver-apiJonathan Neuschäfer2-0/+131
Move gpio/intro.txt to driver-api/gpio/intro.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: driver-api: Move gpio.rst to gpio/index.rstJonathan Neuschäfer2-1/+1
To make space for more files in the GPIO section, create a Documentation/driver-api/gpio/ directory. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-22firmware: add firmware_request_cache() to help with cache on rebootLuis R. Rodriguez1-0/+14
Some devices have an optimization in place to enable the firmware to be retaineed during a system reboot, so after reboot the device can skip requesting and loading the firmware. This can save up to 1s in load time. The mt7601u 802.11 device happens to be such a device. When these devices retain the firmware on a reboot and then suspend they can miss looking for the firmware on resume. To help with this we need a way to cache the firmware when such an optimization has taken place. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22usb: typec: API for controlling USB Type-C MultiplexersHeikki Krogerus1-11/+62
USB Type-C connectors consist of various muxes and switches that route the pins on the connector to the right locations. The USB Type-C drivers need to be able to control the muxes, as they are the ones that know things like the cable plug orientation, and the current mode that was negotiated with the partner. This introduces a small API for registering and controlling cable plug orientation switches, and separate small API for registering and controlling pin multiplexer/demultiplexer switches that are needed with Accessory/Alternate Modes. Reviewed-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22drivers: base: Unified device connection lookupHeikki Krogerus1-0/+43
Several frameworks - clk, gpio, phy, pmw, etc. - maintain lookup tables for describing connections and provide custom API for handling them. This introduces a single generic lookup table and API for the connections. The motivation for this commit is centralizing the connection lookup, but the goal is to ultimately extract the connection descriptions also from firmware by using the fwnode_graph_* functions and other mechanisms that are available. Reviewed-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-20rename: _request_firmware_load() fw_load_sysfs_fallback()Luis R. Rodriguez1-1/+1
This reflects much clearer what is being done. While at it, kdoc'ify it. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-20scsi: remove the old scsi_module.c initialization modelChristoph Hellwig1-6/+0
After more than 15 years all users of this legacy interface are finally gone. Rest in peace! Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-03-06uio_hv_generic: support sub-channelsStephen Hemminger1-0/+5
Use sysfs to allow supporting sub-channels. The userspace application makes request to host to create sub-channels and the UIO kernel driver populates the sysfs per-channel directory with a binary attribute file that can be used to read/write ring. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-19linux-next: SLIMbus: doc: Fix a warning "Title underline too short"Masanari Iida1-1/+1
This patch fixes a warning during "make xmldocs" Documentation/driver-api/slimbus.rst:93: WARNING: Title underline too short. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-02-16mtd: nand: move raw NAND related code to the raw/ subdirBoris Brezillon1-4/+4
As part of the process of sharing more code between different NAND based devices, we need to move all raw NAND related code to the raw/ subdirectory. Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-02-02s390/docs: reword airq sectionCornelia Huck1-4/+9
Also mention the iv helpers as well. Signed-off-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-02s390/docs: mention subchannel typesCornelia Huck1-0/+19
Since the original inception of the s390-drivers document, the common I/O layer has grown support for more types of subchannels. Give at least a pointer for the various types. Signed-off-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-01Merge tag 'char-misc-4.16-rc1' of ↵Linus Torvalds5-7/+370
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big pull request for char/misc drivers for 4.16-rc1. There's a lot of stuff in here. Three new driver subsystems were added for various types of hardware busses: - siox - slimbus - soundwire as well as a new vboxguest subsystem for the VirtualBox hypervisor drivers. There's also big updates from the FPGA subsystem, lots of Android binder fixes, the usual handful of hyper-v updates, and lots of other smaller driver updates. All of these have been in linux-next for a long time, with no reported issues" * tag 'char-misc-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (155 commits) char: lp: use true or false for boolean values android: binder: use VM_ALLOC to get vm area android: binder: Use true and false for boolean values lkdtm: fix handle_irq_event symbol for INT_HW_IRQ_EN EISA: Delete error message for a failed memory allocation in eisa_probe() EISA: Whitespace cleanup misc: remove AVR32 dependencies virt: vbox: Add error mapping for VERR_INVALID_NAME and VERR_NO_MORE_FILES soundwire: Fix a signedness bug uio_hv_generic: fix new type mismatch warnings uio_hv_generic: fix type mismatch warnings auxdisplay: img-ascii-lcd: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE uio_hv_generic: add rescind support uio_hv_generic: check that host supports monitor page uio_hv_generic: create send and receive buffers uio: document uio_hv_generic regions doc: fix documentation about uio_hv_generic vmbus: add monitor_id and subchannel_id to sysfs per channel vmbus: fix ABI documentation uio_hv_generic: use ISR callback method ...
2018-02-01Merge tag 'driver-core-4.16-rc1' of ↵Linus Torvalds2-7/+2
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of "big" driver core patches for 4.16-rc1. The majority of the work here is in the firmware subsystem, with reworks to try to attempt to make the code easier to handle in the long run, but no functional change. There's also some tree-wide sysfs attribute fixups with lots of acks from the various subsystem maintainers, as well as a handful of other normal fixes and changes. And finally, some license cleanups for the driver core and sysfs code. All have been in linux-next for a while with no reported issues" * tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (48 commits) device property: Define type of PROPERTY_ENRTY_*() macros device property: Reuse property_entry_free_data() device property: Move property_entry_free_data() upper firmware: Fix up docs referring to FIRMWARE_IN_KERNEL firmware: Drop FIRMWARE_IN_KERNEL Kconfig option USB: serial: keyspan: Drop firmware Kconfig options sysfs: remove DEBUG defines sysfs: use SPDX identifiers drivers: base: add coredump driver ops sysfs: add attribute specification for /sysfs/devices/.../coredump test_firmware: fix missing unlock on error in config_num_requests_store() test_firmware: make local symbol test_fw_config static sysfs: turn WARN() into pr_warn() firmware: Fix a typo in fallback-mechanisms.rst treewide: Use DEVICE_ATTR_WO treewide: Use DEVICE_ATTR_RO treewide: Use DEVICE_ATTR_RW sysfs.h: Use octal permissions component: add debugfs support bus: simple-pm-bus: convert bool SIMPLE_PM_BUS to tristate ...
2018-02-01Merge tag 'docs-4.16' of git://git.lwn.net/linuxLinus Torvalds3-7/+68
Pull documentation updates from Jonathan Corbet: "Documentation updates for 4.16. New stuff includes refcount_t documentation, errseq documentation, kernel-doc support for nested structure definitions, the removal of lots of crufty kernel-doc support for unused formats, SPDX tag documentation, the beginnings of a manual for subsystem maintainers, and lots of fixes and updates. As usual, some of the changesets reach outside of Documentation/ to effect kerneldoc comment fixes. It also adds the new LICENSES directory, of which Thomas promises I do not need to be the maintainer" * tag 'docs-4.16' of git://git.lwn.net/linux: (65 commits) linux-next: docs-rst: Fix typos in kfigure.py linux-next: DOC: HWPOISON: Fix path to debugfs in hwpoison.txt Documentation: Fix misconversion of #if docs: add index entry for networking/msg_zerocopy Documentation: security/credentials.rst: explain need to sort group_list LICENSES: Add MPL-1.1 license LICENSES: Add the GPL 1.0 license LICENSES: Add Linux syscall note exception LICENSES: Add the MIT license LICENSES: Add the BSD-3-clause "Clear" license LICENSES: Add the BSD 3-clause "New" or "Revised" License LICENSES: Add the BSD 2-clause "Simplified" license LICENSES: Add the LGPL-2.1 license LICENSES: Add the LGPL 2.0 license LICENSES: Add the GPL 2.0 license Documentation: Add license-rules.rst to describe how to properly identify file licenses scripts: kernel_doc: better handle show warnings logic fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at doc: md: Fix a file name to md-fault.c in fault-injection.txt errseq: Add to documentation tree ...
2018-01-31Merge tag 'dmaengine-4.16-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds1-21/+17
Pull dmaengine updates from Vinod Koul: "This time is smallish update with updates mainly to drivers: - updates to xilinx and zynqmp dma controllers - update reside calculation for rcar controller - more RSTify fixes for documentation - add support for race free transfer termination and updating for users for that - support for new rev of hidma with addition new APIs to get device match data in ACPI/OF - random updates to bunch of other drivers" * tag 'dmaengine-4.16-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (47 commits) dmaengine: dmatest: fix container_of member in dmatest_callback dmaengine: stm32-dmamux: Remove unnecessary platform_get_resource() error check dmaengine: sprd: statify 'sprd_dma_prep_dma_memcpy' dmaengine: qcom_hidma: simplify DT resource parsing dmaengine: xilinx_dma: Free BD consistent memory dmaengine: xilinx_dma: Fix warning variable prev set but not used dmaengine: xilinx_dma: properly configure the SG mode bit in the driver for cdma dmaengine: doc: format struct fields using monospace dmaengine: doc: fix bullet list formatting dmaengine: ti-dma-crossbar: Fix event mapping for TPCC_EVT_MUX_60_63 dmaengine: cppi41: Fix channel queues array size check dmaengine: imx-sdma: Add MODULE_FIRMWARE dmaengine: xilinx_dma: Fix typos dmaengine: xilinx_dma: Differentiate probe based on the ip type dmaengine: xilinx_dma: fix style issues from checkpatch dmaengine: xilinx_dma: Fix kernel doc warnings dmaengine: xilinx_dma: Fix race condition in the driver for multiple descriptor scenario dmaeninge: xilinx_dma: Fix bug in multiple frame stores scenario in vdma dmaengine: xilinx_dma: Check for channel idle state before submitting dma descriptor dmaengine: zynqmp_dma: Fix race condition in the probe ...
2018-01-31Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-1/+9
Pull SCSI updates from James Bottomley: "This is mostly updates of the usual driver suspects: arcmsr, scsi_debug, mpt3sas, lpfc, cxlflash, qla2xxx, aacraid, megaraid_sas, hisi_sas. We also have a rework of the libsas hotplug handling to make it more robust, a slew of 32 bit time conversions and fixes, and a host of the usual minor updates and style changes. The biggest potential for regressions is the libsas hotplug changes, but so far they seem stable under testing" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (313 commits) scsi: qla2xxx: Fix logo flag for qlt_free_session_done() scsi: arcmsr: avoid do_gettimeofday scsi: core: Add VENDOR_SPECIFIC sense code definitions scsi: qedi: Drop cqe response during connection recovery scsi: fas216: fix sense buffer initialization scsi: ibmvfc: Remove unneeded semicolons scsi: hisi_sas: fix a bug in hisi_sas_dev_gone() scsi: hisi_sas: directly attached disk LED feature for v2 hw scsi: hisi_sas: devicetree: bindings: add LED feature for v2 hw scsi: megaraid_sas: NVMe passthrough command support scsi: megaraid: use ktime_get_real for firmware time scsi: fnic: use 64-bit timestamps scsi: qedf: Fix error return code in __qedf_probe() scsi: devinfo: fix format of the device list scsi: qla2xxx: Update driver version to 10.00.00.05-k scsi: qla2xxx: Add XCB counters to debugfs scsi: qla2xxx: Fix queue ID for async abort with Multiqueue scsi: qla2xxx: Fix warning for code intentation in __qla24xx_handle_gpdb_event() scsi: qla2xxx: Fix warning during port_name debug print scsi: qla2xxx: Fix warning in qla2x00_async_iocb_timeout() ...
2018-01-29Merge tag 'pm-4.16-rc1' of ↵Linus Torvalds1-10/+44
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "This includes some infrastructure changes in the PM core, mostly related to integration between runtime PM and system-wide suspend and hibernation, plus some driver changes depending on them and fixes for issues in that area which have become quite apparent recently. Also included are changes making more x86-based systems use the Low Power Sleep S0 _DSM interface by default, which turned out to be necessary to handle power button wakeups from suspend-to-idle on Surface Pro3. On the cpufreq front we have fixes and cleanups in the core, some new hardware support, driver updates and the removal of some unused code from the CPU cooling thermal driver. Apart from this, the Operating Performance Points (OPP) framework is prepared to be used with power domains in the future and there is a usual bunch of assorted fixes and cleanups. Specifics: - Define a PM driver flag allowing drivers to request that their devices be left in suspend after system-wide transitions to the working state if possible and add support for it to the PCI bus type and the ACPI PM domain (Rafael Wysocki). - Make the PM core carry out optimizations for devices with driver PM flags set in some cases and make a few drivers set those flags (Rafael Wysocki). - Fix and clean up wrapper routines allowing runtime PM device callbacks to be re-used for system-wide PM, change the generic power domains (genpd) framework to stop using those routines incorrectly and fix up a driver depending on that behavior of genpd (Rafael Wysocki, Ulf Hansson, Geert Uytterhoeven). - Fix and clean up the PM core's device wakeup framework and re-factor system-wide PM core code related to device wakeup (Rafael Wysocki, Ulf Hansson, Brian Norris). - Make more x86-based systems use the Low Power Sleep S0 _DSM interface by default (to fix power button wakeup from suspend-to-idle on Surface Pro3) and add a kernel command line switch to tell it to ignore the system sleep blacklist in the ACPI core (Rafael Wysocki). - Fix a race condition related to cpufreq governor module removal and clean up the governor management code in the cpufreq core (Rafael Wysocki). - Drop the unused generic code related to the handling of the static power energy usage model in the CPU cooling thermal driver along with the corresponding documentation (Viresh Kumar). - Add mt2712 support to the Mediatek cpufreq driver (Andrew-sh Cheng). - Add a new operating point to the imx6ul and imx6q cpufreq drivers and switch the latter to using clk_bulk_get() (Anson Huang, Dong Aisheng). - Add support for multiple regulators to the TI cpufreq driver along with a new DT binding related to that and clean up that driver somewhat (Dave Gerlach). - Fix a powernv cpufreq driver regression leading to incorrect CPU frequency reporting, fix that driver to deal with non-continguous P-states correctly and clean it up (Gautham Shenoy, Shilpasri Bhat). - Add support for frequency scaling on Armada 37xx SoCs through the generic DT cpufreq driver (Gregory CLEMENT). - Fix error code paths in the mvebu cpufreq driver (Gregory CLEMENT). - Fix a transition delay setting regression in the longhaul cpufreq driver (Viresh Kumar). - Add Skylake X (server) support to the intel_pstate cpufreq driver and clean up that driver somewhat (Srinivas Pandruvada). - Clean up the cpufreq statistics collection code (Viresh Kumar). - Drop cluster terminology and dependency on physical_package_id from the PSCI driver and drop dependency on arm_big_little from the SCPI cpufreq driver (Sudeep Holla). - Add support for system-wide suspend and resume to the RAPL power capping driver and drop a redundant semicolon from it (Zhen Han, Luis de Bethencourt). - Make SPI domain validation (in the SCSI SPI transport driver) and system-wide suspend mutually exclusive as they rely on the same underlying mechanism and cannot be carried out at the same time (Bart Van Assche). - Fix the computation of the amount of memory to preallocate in the hibernation core and clean up one function in there (Rainer Fiebig, Kyungsik Lee). - Prepare the Operating Performance Points (OPP) framework for being used with power domains and clean up one function in it (Viresh Kumar, Wei Yongjun). - Clean up the generic sysfs interface for device PM (Andy Shevchenko). - Fix several minor issues in power management frameworks and clean them up a bit (Arvind Yadav, Bjorn Andersson, Geert Uytterhoeven, Gustavo Silva, Julia Lawall, Luis de Bethencourt, Paul Gortmaker, Sergey Senozhatsky, gaurav jindal). - Make it easier to disable PM via Kconfig (Mark Brown). - Clean up the cpupower and intel_pstate_tracer utilities (Doug Smythies, Laura Abbott)" * tag 'pm-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (89 commits) PCI / PM: Remove spurious semicolon cpufreq: scpi: remove arm_big_little dependency drivers: psci: remove cluster terminology and dependency on physical_package_id powercap: intel_rapl: Fix trailing semicolon dmaengine: rcar-dmac: Make DMAC reinit during system resume explicit PM / runtime: Allow no callbacks in pm_runtime_force_suspend|resume() PM / hibernate: Drop unused parameter of enough_swap PM / runtime: Check ignore_children in pm_runtime_need_not_resume() PM / runtime: Rework pm_runtime_force_suspend/resume() PM / genpd: Stop/start devices without pm_runtime_force_suspend/resume() cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin cpufreq: intel_pstate: Add Skylake servers support cpufreq: intel_pstate: Replace bxt_funcs with core_funcs platform/x86: surfacepro3: Support for wakeup from suspend-to-idle ACPI / PM: Use Low Power S0 Idle on more systems PM / wakeup: Print warn if device gets enabled as wakeup source during sleep PM / domains: Don't skip driver's ->suspend|resume_noirq() callbacks PM / core: Propagate wakeup_path status flag in __device_suspend_late() PM / core: Re-structure code for clearing the direct_complete flag powercap: add suspend and resume mechanism for SOC power limit ...
2018-01-25firmware: Fix up docs referring to FIRMWARE_IN_KERNELBenjamin Gilbert1-6/+1
We've removed the option, so stop talking about it. Signed-off-by: Benjamin Gilbert <benjamin.gilbert@coreos.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-12Merge remote-tracking branches 'asoc/topic/hdac_hdmi', ↵Mark Brown2-0/+52
'asoc/topic/hisilicon', 'asoc/topic/iio' and 'asoc/topic/max98373' into asoc-next
2018-01-10uio_hv_generic: add rescind supportStephen Hemminger1-0/+4
When host rescinds the device, the UIO driver will clear the interrupt state and notify application. The read (or write) on the interrupt FD will then fail with -EIO. This is simpler than adding lots extra uevent stuff inside UIO. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10uio_hv_generic: create send and receive buffersStephen Hemminger1-0/+2
Map in receive and send buffers for networking in UIO device. These buffers are special and need to be setup by kernel API's; userspace can not do it. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10uio: document uio_hv_generic regionsStephen Hemminger1-0/+5
Describe the regions present with uio_hv_generic in documentation for driver API. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10doc: fix documentation about uio_hv_genericStephen Hemminger1-7/+8
The vmbus sysfs file names changed in commit f6b2db084b65 ("vmbus: make sysfs names consistent with PCI") and the uio documenatation does not match the current names. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10docs: driver-api: add iio hw consumer sectionArnaud Pouliquen2-0/+52
This adds a section about the Hardware consumer API of the IIO subsystem to the driver API documentation. Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-01-09firmware: Fix a typo in fallback-mechanisms.rstMasanari Iida1-1/+1
This patch fix a spelling typo found in fallback-mechanisms.rst Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-08dmaengine: doc: format struct fields using monospaceLuca Ceresoli1-6/+6
Monospace is more readable and is also used elsewhere in the docs. Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2018-01-08dmaengine: doc: fix bullet list formattingLuca Ceresoli1-16/+12
The bullet list documenting the 'struct dma_device' fields has several nesting errors, making it render improperly. It also has incoherent formatting: some fields have a description in the same bullet, some in a sub-bullet. Fix both to have a correct and coherent formatting. Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2018-01-03PM / core: Direct DPM_FLAG_LEAVE_SUSPENDED handlingRafael J. Wysocki1-0/+9
Make the PM core handle DPM_FLAG_LEAVE_SUSPENDED directly for devices whose "noirq", "late" and "early" driver callbacks are invoked directly by it. Namely, make it skip all of the system-wide resume callbacks for such devices with DPM_FLAG_LEAVE_SUSPENDED set if they are in runtime suspend during the "noirq" phase of system-wide suspend (or analogous) transitions or the system transition under way is a proper suspend (rather than anything related to hibernation) and the device's wakeup settings are compatible with runtime PM (that is, the device cannot generate wakeup signals at all or it is allowed to wake up the system from sleep). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-03PM / core: Direct DPM_FLAG_SMART_SUSPEND optimizationRafael J. Wysocki1-8/+10
Make the PM core avoid invoking the "late" and "noirq" system-wide suspend (or analogous) callbacks provided by device drivers directly for devices with DPM_FLAG_SMART_SUSPEND set that are in runtime suspend during the "late" and "noirq" phases of system-wide suspend (or analogous) transitions. That is only done for devices without any middle-layer "late" and "noirq" suspend callbacks (to avoid confusing the middle layer if there is one). The underlying observation is that runtime PM is disabled for devices during the "late" and "noirq" system-wide suspend phases, so if they remain in runtime suspend from the "late" phase forward, it doesn't make sense to invoke the "late" and "noirq" callbacks provided by the drivers for them (arguably, the device is already suspended and in the right state). Thus, if the remaining driver suspend callbacks are to be invoked directly by the core, they can be skipped. This change really makes it possible for, say, platform device drivers to re-use runtime PM suspend and resume callbacks by pointing ->suspend_late and ->resume_early, respectively (and possibly the analogous hibernation-related callback pointers too), to them without adding any extra "is the device already suspended?" type of checks to the callback routines, as long as they will be invoked directly by the core. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-21usb: doc: Update document for USB3 debug port usageLu Baolu1-0/+52
Update Documentation/driver-api/usb/usb3-debug-port.rst. This update includes the guide for using xHCI debug capability based TTY serial link. Cc: Mathias Nyman <mathias.nyman@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-19Documentation: Add SoundWire summarySanyog Kale3-0/+223
SoundWire is a new Linux bus which implements a new MIPI bus protocol 'SoundWire'. The summary of SoundWire bus and API is documented in the 'summary' file. Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com> Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19Documentation: Add SLIMbus summarySagar Dharia2-0/+128
SLIMbus (Serial Low Power Interchip Media Bus) is a specification developed by MIPI (Mobile Industry Processor Interface) alliance. SLIMbus is a 2-wire implementation, which is used to communicate with peripheral components like audio-codec. The summary of SLIMbus and API is documented in the 'summary' file. Signed-off-by: Sagar Dharia <sdharia@codeaurora.org> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Reviwed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-16Merge back PM core material for v4.16.Rafael J. Wysocki1-2/+25
2017-12-12scsi: documentation: add scsi_common.c to SCSI driver-apiRandy Dunlap1-0/+8
Add exported functions from scsi_common.c to the SCSI driver API documentation. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-12-12docs: refcount_t documentationElena Reshetova1-6/+15
Some functions from refcount_t API provide different memory ordering guarantees that their atomic counterparts. This adds a document outlining these differences ( Documentation/core-api/refcount-vs-atomic.rst) as well as some other minor improvements. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-12Documentation/driver-api/usb: Replace dead linkStefan Tatschner1-1/+1
This link is dead: $ curl -vI http://usb.cs.tum.edu/usbdoc * Could not resolve host: usb.cs.tum.edu * Closing connection 0 curl: (6) Could not resolve host: usb.cs.tum.edu I found the document somewhere else. Let's replace it. Signed-off-by: Stefan Tatschner <stefan.tatschner@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-05scsi: fix another I2O typoRandy Dunlap1-1/+1
Correct another typo I20 to I2O. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-12-04Documentation: fix docs build error after source file removedRandy Dunlap1-3/+0
The pci/htirq.c file was removed so remove it from the documentation file also. Error: Cannot open file ../drivers/pci/htirq.c WARNING: kernel-doc '../scripts/kernel-doc -rst -enable-lineno -export ../drivers/pci/htirq.c' failed with return code 2 Fixes: fd2fa6c18b72 ("x86/PCI: Remove unused HyperTransport interrupt support") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-02dmaengine: doc : Fix warning "Title underline too short" while make xmldocsMasanari Iida1-1/+1
This patch fix following warning during 'make xmldocs' Documentation/driver-api/dmaengine/client.rst:188: WARNING: Title underline too short. Further APIs: ------------ Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-11-27PM / core: Add LEAVE_SUSPENDED driver flagRafael J. Wysocki1-2/+25
Define and document a new driver flag, DPM_FLAG_LEAVE_SUSPENDED, to instruct the PM core and middle-layer (bus type, PM domain, etc.) code that it is desirable to leave the device in runtime suspend after system-wide transitions to the working state (for example, the device may be slow to resume and it may be better to avoid resuming it right away). Generally, the middle-layer code involved in the handling of the device is expected to indicate to the PM core whether or not the device may be left in suspend with the help of the device's power.may_skip_resume status bit. That has to happen in the "noirq" phase of the preceding system suspend (or analogous) transition. The middle layer is then responsible for handling the device as appropriate in its "noirq" resume callback which is executed regardless of whether or not the device may be left suspended, but the other resume callbacks (except for ->complete) will be skipped automatically by the core if the device really can be left in suspend. The additional power.must_resume status bit introduced for the implementation of this mechanisn is used internally by the PM core to track the requirement to resume the device (which may depend on its children etc). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-11-16Merge tag 'pinctrl-v4.15-1' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin control updates from Linus Walleij: "This is the bulk of pin control changes for the v4.15 kernel cycle: Core: - The pin control Kconfig entry PINCTRL is now turned into a menuconfig option. This obviously has the implication of making the subsystem menu visible in menuconfig. This is happening because of two things: (a) Intel have started to deploy and depend on pin controllers in a way that is affecting users directly. This happens on the highly integrated laptop chipsets named after geographical places: baytrail, broxton, cannonlake, cedarfork, cherryview, denverton, geminilake, lewisburg, merrifield, sunrisepoint... It started a while back and now it is ever more evident that this is crucial infrastructure for x86 laptops and not an embedded obscurity anymore. Users need to be aware. (b) Pin control expanders on I2C and SPI that are arch-agnostic. Currently Semtech SX150X and Microchip MCP28x08 but more are expected. Users will have to be able to configure these in directly for their set-up. - Just go and select GPIOLIB now that we made sure that GPIOLIB is a very vanilla subsystem. Do not depend on it, if we need it, select it. - Exposing the pin control subsystem in menuconfig uncovered a bunch of obscure bugs that are now hopefully fixed, all more or less pertaining to Blackfin. - Unified namespace for cross-calls between pin control and GPIO. - New support for clock skew/delay generic DT bindings and generic pin config options for this. - Minor documentation improvements. Various: - The Renesas SH-PFC pin controller has evolved a lot. It seems Renesas are churning out new SoCs by the minute. - A bunch of non-critical fixes for the Rockchip driver. - Improve the use of library functions instead of open coding. - Support the MCP28018 variant in the MCP28x08 driver. - Static constifying" * tag 'pinctrl-v4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (91 commits) pinctrl: gemini: Fix missing pad descriptions pinctrl: Add some depends on HAS_IOMEM pinctrl: samsung/s3c24xx: add CONFIG_OF dependency pinctrl: gemini: Fix GMAC groups pinctrl: qcom: spmi-gpio: Add pmi8994 gpio support pinctrl: ti-iodelay: remove redundant unused variable dev pinctrl: max77620: Use common error handling code in max77620_pinconf_set() pinctrl: gemini: Implement clock skew/delay config pinctrl: gemini: Use generic DT parser pinctrl: Add skew-delay pin config and bindings pinctrl: armada-37xx: Add edge both type gpio irq support pinctrl: uniphier: remove eMMC hardware reset pin-mux pinctrl: rockchip: Add iomux-route switching support for rk3288 pinctrl: intel: Add Intel Cedar Fork PCH pin controller support pinctrl: intel: Make offset to interrupt status register configurable pinctrl: sunxi: Enforce the strict mode by default pinctrl: sunxi: Disable strict mode for old pinctrl drivers pinctrl: sunxi: Introduce the strict flag pinctrl: sh-pfc: Save/restore registers for PSCI system suspend pinctrl: sh-pfc: r8a7796: Use generic IOCTRL register description ...
2017-11-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-3/+0
Pull networking updates from David Miller: "Highlights: 1) Maintain the TCP retransmit queue using an rbtree, with 1GB windows at 100Gb this really has become necessary. From Eric Dumazet. 2) Multi-program support for cgroup+bpf, from Alexei Starovoitov. 3) Perform broadcast flooding in hardware in mv88e6xxx, from Andrew Lunn. 4) Add meter action support to openvswitch, from Andy Zhou. 5) Add a data meta pointer for BPF accessible packets, from Daniel Borkmann. 6) Namespace-ify almost all TCP sysctl knobs, from Eric Dumazet. 7) Turn on Broadcom Tags in b53 driver, from Florian Fainelli. 8) More work to move the RTNL mutex down, from Florian Westphal. 9) Add 'bpftool' utility, to help with bpf program introspection. From Jakub Kicinski. 10) Add new 'cpumap' type for XDP_REDIRECT action, from Jesper Dangaard Brouer. 11) Support 'blocks' of transformations in the packet scheduler which can span multiple network devices, from Jiri Pirko. 12) TC flower offload support in cxgb4, from Kumar Sanghvi. 13) Priority based stream scheduler for SCTP, from Marcelo Ricardo Leitner. 14) Thunderbolt networking driver, from Amir Levy and Mika Westerberg. 15) Add RED qdisc offloadability, and use it in mlxsw driver. From Nogah Frankel. 16) eBPF based device controller for cgroup v2, from Roman Gushchin. 17) Add some fundamental tracepoints for TCP, from Song Liu. 18) Remove garbage collection from ipv6 route layer, this is a significant accomplishment. From Wei Wang. 19) Add multicast route offload support to mlxsw, from Yotam Gigi" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2177 commits) tcp: highest_sack fix geneve: fix fill_info when link down bpf: fix lockdep splat net: cdc_ncm: GetNtbFormat endian fix openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_start netem: remove unnecessary 64 bit modulus netem: use 64 bit divide by rate tcp: Namespace-ify sysctl_tcp_default_congestion_control net: Protect iterations over net::fib_notifier_ops in fib_seq_sum() ipv6: set all.accept_dad to 0 by default uapi: fix linux/tls.h userspace compilation error usbnet: ipheth: prevent TX queue timeouts when device not ready vhost_net: conditionally enable tx polling uapi: fix linux/rxrpc.h userspace compilation errors net: stmmac: fix LPI transitioning for dwmac4 atm: horizon: Fix irq release error net-sysfs: trigger netlink notification on ifalias change via sysfs openvswitch: Using kfree_rcu() to simplify the code openvswitch: Make local function ovs_nsh_key_attr_size() static openvswitch: Fix return value check in ovs_meter_cmd_features() ...
2017-11-15Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-1/+1
Pull SCSI updates from James Bottomley: "This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas, megaraid_sas, pm80xx, mpt3sas, be2iscsi, hpsa. and a host of minor updates. There's no major behaviour change or additions to the core in all of this, so the potential for regressions should be small (biggest potential being in the scsi error handler changes)" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (203 commits) scsi: lpfc: Fix hard lock up NMI in els timeout handling. scsi: mpt3sas: remove a stray KERN_INFO scsi: mpt3sas: cleanup _scsih_pcie_enumeration_event() scsi: aacraid: use timespec64 instead of timeval scsi: scsi_transport_fc: add 64GBIT and 128GBIT port speed definitions scsi: qla2xxx: Suppress a kernel complaint in qla_init_base_qpair() scsi: mpt3sas: fix dma_addr_t casts scsi: be2iscsi: Use kasprintf scsi: storvsc: Avoid excessive host scan on controller change scsi: lpfc: fix kzalloc-simple.cocci warnings scsi: mpt3sas: Update mpt3sas driver version. scsi: mpt3sas: Fix sparse warnings scsi: mpt3sas: Fix nvme drives checking for tlr. scsi: mpt3sas: NVMe drive support for BTDHMAPPING ioctl command and log info scsi: mpt3sas: Add-Task-management-debug-info-for-NVMe-drives. scsi: mpt3sas: scan and add nvme device after controller reset scsi: mpt3sas: Set NVMe device queue depth as 128 scsi: mpt3sas: Handle NVMe PCIe device related events generated from firmware. scsi: mpt3sas: API's to remove nvme drive from sml scsi: mpt3sas: API 's to support NVMe drive addition to SML ...
2017-11-14Merge tag 'pm-4.15-rc1' of ↵Linus Torvalds1-2/+59
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "There are no real big ticket items here this time. The most noticeable change is probably the relocation of the OPP (Operating Performance Points) framework to its own directory under drivers/ as it has grown big enough for that. Also Viresh is now going to maintain it and send pull requests for it to me, so you will see this change in the git history going forward (but still not right now). Another noticeable set of changes is the modifications of the PM core, the PCI subsystem and the ACPI PM domain to allow of more integration between system-wide suspend/resume and runtime PM. For now it's just a way to avoid resuming devices from runtime suspend unnecessarily during system suspend (if the driver sets a flag to indicate its readiness for that) and in the works is an analogous mechanism to allow devices to stay suspended after system resume. In addition to that, we have some changes related to supporting frequency-invariant CPU utilization metrics in the scheduler and in the schedutil cpufreq governor on ARM and changes to add support for device performance states to the generic power domains (genpd) framework. The rest is mostly fixes and cleanups of various sorts. Specifics: - Relocate the OPP (Operating Performance Points) framework to its own directory under drivers/ and add support for power domain performance states to it (Viresh Kumar). - Modify the PM core, the PCI bus type and the ACPI PM domain to support power management driver flags allowing device drivers to specify their capabilities and preferences regarding the handling of devices with enabled runtime PM during system suspend/resume and clean up that code somewhat (Rafael Wysocki, Ulf Hansson). - Add frequency-invariant accounting support to the task scheduler on ARM and ARM64 (Dietmar Eggemann). - Fix PM QoS device resume latency framework to prevent "no restriction" requests from overriding requests with specific requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP device PM QoS flag (Rafael Wysocki). - Drop legacy class suspend/resume operations from the PM core and drop legacy bus type suspend and resume callbacks from ARM/locomo (Rafael Wysocki). - Add min/max frequency support to devfreq and clean it up somewhat (Chanwoo Choi). - Rework wakeup support in the generic power domains (genpd) framework and update some of its users accordingly (Geert Uytterhoeven). - Convert timers in the PM core to use timer_setup() (Kees Cook). - Add support for exposing the SLP_S0 (Low Power S0 Idle) residency counter based on the LPIT ACPI table on Intel platforms (Srinivas Pandruvada). - Add per-CPU PM QoS resume latency support to the ladder cpuidle governor (Ramesh Thomas). - Fix a deadlock between the wakeup notify handler and the notifier removal in the ACPI core (Ville Syrjälä). - Fix a cpufreq schedutil governor issue causing it to use stale cached frequency values sometimes (Viresh Kumar). - Fix an issue in the system suspend core support code causing wakeup events detection to fail in some cases (Rajat Jain). - Fix the generic power domains (genpd) framework to prevent the PM core from using the direct-complete optimization with it as that is guaranteed to fail (Ulf Hansson). - Fix a minor issue in the cpuidle core and clean it up a bit (Gaurav Jindal, Nicholas Piggin). - Fix and clean up the intel_idle and ARM cpuidle drivers (Jason Baron, Len Brown, Leo Yan). - Fix a couple of minor issues in the OPP framework and clean it up (Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan). - Fix and clean up some cpufreq drivers and fix a minor issue in the cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro Yamada, Robert Jarzmik, Zumeng Chen). - Fix minor issues in the system suspend and hibernation core, in power management documentation and in the AVS (Adaptive Voltage Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches, Rafael Wysocki). - Fix some issues in the cpupower utility and document that Shuah Khan is going to maintain it going forward (Prarit Bhargava, Shuah Khan)" * tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (88 commits) tools/power/cpupower: add libcpupower.so.0.0.1 to .gitignore tools/power/cpupower: Add 64 bit library detection intel_idle: Graceful probe failure when MWAIT is disabled cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq freezer: Fix typo in freezable_schedule_timeout() comment PM / s2idle: Clear the events_check_enabled flag cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const cpufreq: arm_big_little: make function arguments and structure pointer const cpuidle: Avoid assignment in if () argument cpuidle: Clean up cpuidle_enable_device() error handling a bit ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare() cpuidle: ladder: Add per CPU PM QoS resume latency support PM / QoS: Fix device resume latency framework PM / domains: Rework governor code to be more consistent PM / Domains: Remove gpd_dev_ops.active_wakeup() callback soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP ...
2017-11-13Merge branch 'pm-core'Rafael J. Wysocki1-0/+34
* pm-core: ACPI / PM: Take SMART_SUSPEND driver flag into account PCI / PM: Take SMART_SUSPEND driver flag into account PCI / PM: Drop unnecessary invocations of pcibios_pm_ops callbacks PM / core: Add SMART_SUSPEND driver flag PCI / PM: Use the NEVER_SKIP driver flag PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags PM / core: Convert timers to use timer_setup() PM / core: Fix kerneldoc comments of four functions PM / core: Drop legacy class suspend/resume operations
2017-11-13Merge branch 'pm-sleep'Rafael J. Wysocki1-1/+24
* pm-sleep: freezer: Fix typo in freezable_schedule_timeout() comment PM / s2idle: Clear the events_check_enabled flag PM / sleep: Remove pm_complete_with_resume_check() PM: ARM: locomo: Drop suspend and resume bus type callbacks PM: Use a more common logging style PM: Document rules on using pm_runtime_resume() in system suspend callbacks
2017-11-06PM / core: Add SMART_SUSPEND driver flagRafael J. Wysocki1-0/+20
Define and document a SMART_SUSPEND flag to instruct bus types and PM domains that the system suspend callbacks provided by the driver can cope with runtime-suspended devices, so from the driver's perspective it should be safe to leave devices in runtime suspend during system suspend. Setting that flag may also cause middle-layer code (bus types, PM domains etc.) to skip invocations of the ->suspend_late and ->suspend_noirq callbacks provided by the driver if the device is in runtime suspend at the beginning of the "late" phase of the system-wide suspend transition, in which case the driver's system-wide resume callbacks may be invoked back-to-back with its ->runtime_suspend callback, so the driver has to be able to cope with that too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-11-06PM / core: Add NEVER_SKIP and SMART_PREPARE driver flagsRafael J. Wysocki1-0/+14
The motivation for this change is to provide a way to work around a problem with the direct-complete mechanism used for avoiding system suspend/resume handling for devices in runtime suspend. The problem is that some middle layer code (the PCI bus type and the ACPI PM domain in particular) returns positive values from its system suspend ->prepare callbacks regardless of whether the driver's ->prepare returns a positive value or 0, which effectively prevents drivers from being able to control the direct-complete feature. Some drivers need that control, however, and the PCI bus type has grown its own flag to deal with this issue, but since it is not limited to PCI, it is better to address it by adding driver flags at the core level. To that end, add a driver_flags field to struct dev_pm_info for flags that can be set by device drivers at the probe time to inform the PM core and/or bus types, PM domains and so on on the capabilities and/or preferences of device drivers. Also add two static inline helpers for setting that field and testing it against a given set of flags and make the driver core clear it automatically on driver remove and probe failures. Define and document two PM driver flags related to the direct- complete feature: NEVER_SKIP and SMART_PREPARE that can be used, respectively, to indicate to the PM core that the direct-complete mechanism should never be used for the device and to inform the middle layer code (bus types, PM domains etc) that it can only request the PM core to use the direct-complete mechanism for the device (by returning a positive value from its ->prepare callback) if it also has been requested by the driver. While at it, make the core check pm_runtime_suspended() when setting power.direct_complete so that it doesn't need to be checked by ->prepare callbacks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>