kernel/drivers/acpi/device_pm.c, branch linux-5.1.y

ACPI/PCI: PM: Add missing wakeup.flags.valid checks

2019-06-22T06:09:11Z

[ Upstream commit 9a51c6b1f9e0239a9435db036b212498a2a3b75c ] Both acpi_pci_need_resume() and acpi_dev_needs_resume() check if the current ACPI wakeup configuration of the device matches what is expected as far as system wakeup from sleep states is concerned, as reflected by the device_may_wakeup() return value for the device. However, they only should do that if wakeup.flags.valid is set for the device's ACPI companion, because otherwise the wakeup.prepare_count value for it is meaningless. Add the missing wakeup.flags.valid checks to these functions. Signed-off-by: Rafael J. Wysocki Reviewed-by: Mika Westerberg Signed-off-by: Sasha Levin

ACPI / PM: Export acpi_device_get_power() for use by modular build drivers

2018-10-12T10:29:48Z

Export acpi_device_get_power() for use by modular build drivers. Reviewed-by: Andy Shevchenko Acked-by: Rafael J. Wysocki Signed-off-by: Hans de Goede Signed-off-by: Thierry Reding

PM / Domains: Allow a better error handling of dev_pm_domain_attach()

2018-05-14T20:58:44Z

The callers of dev_pm_domain_attach() currently checks the returned error code for -EPROBE_DEFER and needs to ignore other error codes. This is an unnecessary limitation, which also leads to a rather strange behaviour in the error path. Address this limitation, by changing the return codes from acpi_dev_pm_attach() and genpd_dev_pm_attach(). More precisely, let them return 0, when no PM domain is needed for the device and then return 1, in case the device was successfully attached to its PM domain. In this way, dev_pm_domain_attach(), gets a better understanding of what happens in the attach attempts and also allowing its caller to better act on real errors codes. Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

PM / Domains: Check for existing PM domain in dev_pm_domain_attach()

2018-05-14T20:58:44Z

Instead of checking if an existing PM domain pointer has been assigned in genpd_dev_pm_attach() and acpi_dev_pm_attach(), move the check to the common path in dev_pm_domain_attach(), thus potentially avoid one unnecessary check. Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

ACPI / PM: Allow deeper wakeup power states with no _SxD nor _SxW

2018-03-20T09:27:09Z

acpi_dev_pm_get_state() is used to determine the range of allowable device power states when going into S3 suspend. This is implemented by executing the _S3D and _S3W ACPI methods. Linux follows the ACPI spec behaviour in that when _S3D is implemented and _S3W is not, Linux will not go into a power state deeper than the one returned by _S3D for a wakeup-enabled device. However, this same logic is being applied to the case when neither _S3D nor _S3W are present, and the result is that this function decides that the device must stay in D0 (fully on) state. This is breaking USB wakeups on Asus V222GA and Acer XC-830. _S3D and _S3W are not present, so the USB controller is left in the D0 running state during S3, and hence it is unable to generate a PME# wake event. The ACPI spec is unclear on which power states are permissable for wakeup-enabled devices when both _S3D and _S3W are missing. However, USB wakeups work fine on these platforms under Windows, where device manager shows that they are using D3 device state for the USB controller in S3. I assume that the "max = min" clamping done by the code here is specifically written for the _S3D but no _S3W case. By making the code true to those conditions, avoiding them on these platforms, the controller will be put into D3 state and USB wakeups start working. Additionally I feel that this change makes the code more directly mirror the wording of the ACPI spec and it's associated lack of clarity. Thanks to Mathias Nyman for pointing us in the right direction. Signed-off-by: Daniel Drake Link: http://lkml.kernel.org/r/CAB4CAwf_k-WsF3zL4epm9TKAOu0h=Bv1XhXV_gY3bziOo_NPKA@mail.gmail.com https://phabricator.endlessm.com/T21410 Signed-off-by: Rafael J. Wysocki

Merge back PM core material for v4.16.

2017-12-16T01:05:48Z

PM / sleep: Avoid excess pm_runtime_enable() calls in device_resume()

2017-12-11T13:32:56Z

Middle-layer code doing suspend-time optimizations for devices with the DPM_FLAG_SMART_SUSPEND flag set (currently, the PCI bus type and the ACPI PM domain) needs to make the core skip ->thaw_early and ->thaw callbacks for those devices in some cases and it sets the power.direct_complete flag for them for this purpose. However, it turns out that setting power.direct_complete outside of the PM core is a bad idea as it triggers an excess invocation of pm_runtime_enable() in device_resume(). For this reason, provide a helper to clear power.is_late_suspended and power.is_suspended to be invoked by the middle-layer code in question instead of setting power.direct_complete and make that code call the new helper. Fixes: c4b65157aeef (PCI / PM: Take SMART_SUSPEND driver flag into account) Fixes: 05087360fd7a (ACPI / PM: Take SMART_SUSPEND driver flag into account) Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Acked-by: Bjorn Helgaas

ACPI / PM: Support for LEAVE_SUSPENDED driver flag in ACPI PM domain

2017-11-27T00:20:59Z

Add support for DPM_FLAG_LEAVE_SUSPENDED to the ACPI PM domain by making it (a) set the power.may_skip_resume status bit for devices that, from its perspective, may be left in suspend after system wakeup from sleep and (b) return early from acpi_subsys_resume_noirq() for devices whose remaining resume callbacks during the transition under way are going to be skipped by the PM core. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman

Merge branch 'pm-core'

2017-11-13T00:41:26Z

* 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

ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock

2017-11-08T22:02:43Z

acpi_remove_pm_notifier() ends up calling flush_workqueue() while holding acpi_pm_notifier_lock, and that same lock is taken by by the work via acpi_pm_notify_handler(). This can deadlock. To fix the problem let's split the single lock into two: one to protect the dev->wakeup between the work vs. add/remove, and another one to handle notifier installation vs. removal. After commit a1d14934ea4b "workqueue/lockdep: 'Fix' flush_work() annotation" I was able to kill the machine (Intel Braswell) very easily with 'powertop --auto-tune', runtime suspending i915, and trying to wake it up via the USB keyboard. The cases when it didn't die are presumably explained by lockdep getting disabled by something else (cpu hotplug locking issues usually). Fortunately I still got a lockdep report over netconsole (trickling in very slowly), even though the machine was otherwise practically dead: [ 112.179806] ====================================================== [ 114.670858] WARNING: possible circular locking dependency detected [ 117.155663] 4.13.0-rc6-bsw-bisect-00169-ga1d14934ea4b #119 Not tainted [ 119.658101] ------------------------------------------------------ [ 121.310242] xhci_hcd 0000:00:14.0: xHCI host not responding to stop endpoint command. [ 121.313294] xhci_hcd 0000:00:14.0: xHCI host controller not responding, assume dead [ 121.313346] xhci_hcd 0000:00:14.0: HC died; cleaning up [ 121.313485] usb 1-6: USB disconnect, device number 3 [ 121.313501] usb 1-6.2: USB disconnect, device number 4 [ 134.747383] kworker/0:2/47 is trying to acquire lock: [ 137.220790] (acpi_pm_notifier_lock){+.+.}, at: [] acpi_pm_notify_handler+0x2f/0x80 [ 139.721524] [ 139.721524] but task is already holding lock: [ 144.672922] ((&dpc->work)){+.+.}, at: [] process_one_work+0x160/0x720 [ 147.184450] [ 147.184450] which lock already depends on the new lock. [ 147.184450] [ 154.604711] [ 154.604711] the existing dependency chain (in reverse order) is: [ 159.447888] [ 159.447888] -> #2 ((&dpc->work)){+.+.}: [ 164.183486] __lock_acquire+0x1255/0x13f0 [ 166.504313] lock_acquire+0xb5/0x210 [ 168.778973] process_one_work+0x1b9/0x720 [ 171.030316] worker_thread+0x4c/0x440 [ 173.257184] kthread+0x154/0x190 [ 175.456143] ret_from_fork+0x27/0x40 [ 177.624348] [ 177.624348] -> #1 ("kacpi_notify"){+.+.}: [ 181.850351] __lock_acquire+0x1255/0x13f0 [ 183.941695] lock_acquire+0xb5/0x210 [ 186.046115] flush_workqueue+0xdd/0x510 [ 190.408153] acpi_os_wait_events_complete+0x31/0x40 [ 192.625303] acpi_remove_notify_handler+0x133/0x188 [ 194.820829] acpi_remove_pm_notifier+0x56/0x90 [ 196.989068] acpi_dev_pm_detach+0x5f/0xa0 [ 199.145866] dev_pm_domain_detach+0x27/0x30 [ 201.285614] i2c_device_probe+0x100/0x210 [ 203.411118] driver_probe_device+0x23e/0x310 [ 205.522425] __driver_attach+0xa3/0xb0 [ 207.634268] bus_for_each_dev+0x69/0xa0 [ 209.714797] driver_attach+0x1e/0x20 [ 211.778258] bus_add_driver+0x1bc/0x230 [ 213.837162] driver_register+0x60/0xe0 [ 215.868162] i2c_register_driver+0x42/0x70 [ 217.869551] 0xffffffffa0172017 [ 219.863009] do_one_initcall+0x45/0x170 [ 221.843863] do_init_module+0x5f/0x204 [ 223.817915] load_module+0x225b/0x29b0 [ 225.757234] SyS_finit_module+0xc6/0xd0 [ 227.661851] do_syscall_64+0x5c/0x120 [ 229.536819] return_from_SYSCALL_64+0x0/0x7a [ 231.392444] [ 231.392444] -> #0 (acpi_pm_notifier_lock){+.+.}: [ 235.124914] check_prev_add+0x44e/0x8a0 [ 237.024795] __lock_acquire+0x1255/0x13f0 [ 238.937351] lock_acquire+0xb5/0x210 [ 240.840799] __mutex_lock+0x75/0x940 [ 242.709517] mutex_lock_nested+0x1c/0x20 [ 244.551478] acpi_pm_notify_handler+0x2f/0x80 [ 246.382052] acpi_ev_notify_dispatch+0x44/0x5c [ 248.194412] acpi_os_execute_deferred+0x14/0x30 [ 250.003925] process_one_work+0x1ec/0x720 [ 251.803191] worker_thread+0x4c/0x440 [ 253.605307] kthread+0x154/0x190 [ 255.387498] ret_from_fork+0x27/0x40 [ 257.153175] [ 257.153175] other info that might help us debug this: [ 257.153175] [ 262.324392] Chain exists of: [ 262.324392] acpi_pm_notifier_lock --> "kacpi_notify" --> (&dpc->work) [ 262.324392] [ 267.391997] Possible unsafe locking scenario: [ 267.391997] [ 270.758262] CPU0 CPU1 [ 272.431713] ---- ---- [ 274.060756] lock((&dpc->work)); [ 275.646532] lock("kacpi_notify"); [ 277.260772] lock((&dpc->work)); [ 278.839146] lock(acpi_pm_notifier_lock); [ 280.391902] [ 280.391902] *** DEADLOCK *** [ 280.391902] [ 284.986385] 2 locks held by kworker/0:2/47: [ 286.524895] #0: ("kacpi_notify"){+.+.}, at: [] process_one_work+0x160/0x720 [ 288.112927] #1: ((&dpc->work)){+.+.}, at: [] process_one_work+0x160/0x720 [ 289.727725] Fixes: c072530f391e (ACPI / PM: Revork the handling of ACPI device wakeup notifications) Signed-off-by: Ville Syrjälä Cc: 3.17+ # 3.17+ Signed-off-by: Rafael J. Wysocki