From 1f112cee07b314e244ee9e71d9c1e6950dc13327 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 11 Apr 2011 22:54:42 +0200 Subject: PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKS Xen save/restore is going to use hibernate device callbacks for quiescing devices and putting them back to normal operations and it would need to select CONFIG_HIBERNATION for this purpose. However, that also would cause the hibernate interfaces for user space to be enabled, which might confuse user space, because the Xen kernels don't support hibernation. Moreover, it would be wasteful, as it would make the Xen kernels include a substantial amount of code that they would never use. To address this issue introduce new power management Kconfig option CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code that is necessary for the hibernate device callbacks to work and make CONFIG_HIBERNATION select it. Then, Xen save/restore will be able to select CONFIG_HIBERNATE_CALLBACKS without dragging the entire hibernate code along with it. Signed-off-by: Rafael J. Wysocki Tested-by: Shriram Rajagopalan --- drivers/base/power/main.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/base/power/main.c') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 052dc53eef38..fbc5b6e7c591 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -233,7 +233,7 @@ static int pm_op(struct device *dev, } break; #endif /* CONFIG_SUSPEND */ -#ifdef CONFIG_HIBERNATION +#ifdef CONFIG_HIBERNATE_CALLBACKS case PM_EVENT_FREEZE: case PM_EVENT_QUIESCE: if (ops->freeze) { @@ -260,7 +260,7 @@ static int pm_op(struct device *dev, suspend_report_result(ops->restore, error); } break; -#endif /* CONFIG_HIBERNATION */ +#endif /* CONFIG_HIBERNATE_CALLBACKS */ default: error = -EINVAL; } @@ -308,7 +308,7 @@ static int pm_noirq_op(struct device *dev, } break; #endif /* CONFIG_SUSPEND */ -#ifdef CONFIG_HIBERNATION +#ifdef CONFIG_HIBERNATE_CALLBACKS case PM_EVENT_FREEZE: case PM_EVENT_QUIESCE: if (ops->freeze_noirq) { @@ -335,7 +335,7 @@ static int pm_noirq_op(struct device *dev, suspend_report_result(ops->restore_noirq, error); } break; -#endif /* CONFIG_HIBERNATION */ +#endif /* CONFIG_HIBERNATE_CALLBACKS */ default: error = -EINVAL; } -- cgit v1.2.3 From 22110faf8c8e980013790e6a5214de32b3303730 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 26 Apr 2011 11:33:09 +0200 Subject: PM / Wakeup: Fix initialization of wakeup-related device sysfs files It turns out that some PCI devices are only found to be wakeup-capable during registration, in which case, when device_set_wakeup_capable() is called, device_is_registered() already returns 'true' for the given device, but dpm_sysfs_add() hasn't been called for it yet. This leads to situations in which the device's power.can_wakeup flag is not set as requested because of failing wakeup_sysfs_add() and its wakeup-related sysfs files are not created, although they should be present. This is a post-2.6.38 regression introduced by commit cb8f51bdadb7969139c2e39c2defd4cde98c1 (PM: Do not create wakeup sysfs files for devices that cannot wake up). To work around this problem initialize the device's power.entry field to an empty list head and make device_set_wakeup_capable() check if it is still empty before attempting to add the devices wakeup-related sysfs files with wakeup_sysfs_add(). Namely, if power.entry is still empty at this point, device_pm_add() hasn't been called yet for the device and its wakeup-related files will be created later, so device_set_wakeup_capable() doesn't have to create them. Reported-and-tested-by: Tino Keitel Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman --- drivers/base/power/main.c | 1 + drivers/base/power/wakeup.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/base/power/main.c') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index fbc5b6e7c591..abe3ab709e87 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -63,6 +63,7 @@ void device_pm_init(struct device *dev) dev->power.wakeup = NULL; spin_lock_init(&dev->power.lock); pm_runtime_init(dev); + INIT_LIST_HEAD(&dev->power.entry); } /** diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index 4573c83df6dd..abbbd33e8d8a 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -258,7 +258,7 @@ void device_set_wakeup_capable(struct device *dev, bool capable) if (!!dev->power.can_wakeup == !!capable) return; - if (device_is_registered(dev)) { + if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { if (capable) { if (wakeup_sysfs_add(dev)) return; -- cgit v1.2.3