kernel.git/drivers/base/power/domain.c, branch linux-3.2.y

PM / Domains: Fix unsafe iteration over modified list of device links

2017-10-12T14:27:12Z

commit c6e83cac3eda5f7dd32ee1453df2f7abb5c6cd46 upstream. pm_genpd_remove_subdomain() iterates over domain's master_links list and removes matching element thus it has to use safe version of list iteration. Fixes: f721889ff65a ("PM / Domains: Support for generic I/O PM domains (v8)") Signed-off-by: Krzysztof Kozlowski Acked-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki Signed-off-by: Ben Hutchings

Revert "PM / Domains: Fix handling of wakeup devices during system resume"

2013-09-10T00:57:29Z

This reverts commit 5c6156fac087f551cbd57499f4bed2fc614d70cd, which was commit cc85b20780562d404e18a47b9b55b4a5102ae53e upstream. It broke ARM && PM configurations by adding a call to genpd_dev_active_wakeup() which was only added in Linux 3.3. Signed-off-by: Ben Hutchings

PM / Domains: Fix handling of wakeup devices during system resume

2012-04-02T16:52:37Z

commit cc85b20780562d404e18a47b9b55b4a5102ae53e upstream. During system suspend pm_genpd_suspend_noirq() checks if the given device is in a wakeup path (i.e. it appears to be needed for one or more wakeup devices to work or is a wakeup device itself) and if it needs to be "active" for wakeup to work. If that is the case, the function returns 0 without incrementing the device domain's counter of suspended devices and without executing genpd_stop_dev() for the device. In consequence, the device is not stopped (e.g. its clock isn't disabled) and power is always supplied to its domain in the resulting system sleep state. However, pm_genpd_resume_noirq() doesn't repeat that check and it runs genpd_start_dev() and decrements the domain's counter of suspended devices even for the wakeup device that weren't stopped by pm_genpd_suspend_noirq(). As a result, the start callback may be run unnecessarily for them and their domains' counters of suspended devices may become negative. Both outcomes aren't desirable, so fix pm_genpd_resume_noirq() to look for wakeup devices that might not be stopped by during system suspend. Signed-off-by: Rafael J. Wysocki Tested-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

PM / Sleep: Mark devices involved in wakeup signaling during suspend

2011-10-21T22:19:29Z

The generic PM domains code in drivers/base/power/domain.c has to avoid powering off domains that provide power to wakeup devices during system suspend. Currently, however, this only works for wakeup devices directly belonging to the given domain and not for their children (or the children of their children and so on). Thus, if there's a wakeup device whose parent belongs to a power domain handled by the generic PM domains code, the domain will be powered off during system suspend preventing the device from signaling wakeup. To address this problem introduce a device flag, power.wakeup_path, that will be set during system suspend for all wakeup devices, their parents, the parents of their parents and so on. This way, all wakeup paths in the device hierarchy will be marked and the generic PM domains code will only need to avoid powering off domains containing devices whose power.wakeup_path is set. Signed-off-by: Rafael J. Wysocki

PM / Domains: Split device PM domain data into base and need_restore

2011-09-26T18:22:02Z

The struct pm_domain_data data type is defined in such a way that adding new fields specific to the generic PM domains code will require include/linux/pm.h to be modified. As a result, data types used only by the generic PM domains code will be defined in two headers, although they all should be defined in pm_domain.h and pm.h will need to include more headers, which won't be very nice. For this reason change the definition of struct pm_subsys_data so that its domain_data member is a pointer, which will allow struct pm_domain_data to be subclassed by various PM domains implementations. Remove the need_restore member from struct pm_domain_data and make the generic PM domains code subclass it by adding the need_restore member to the new data type. Signed-off-by: Rafael J. Wysocki

PM / Domains: Preliminary support for devices with power.irq_safe set

2011-08-25T13:37:04Z

The generic PM domains framework currently doesn't work with devices whose power.irq_safe flag is set, because runtime PM callbacks for such devices are run with interrupts disabled and the callbacks provided by the generic PM domains framework use domain mutexes and may sleep. However, such devices very well may belong to power domains on some systems, so the generic PM domains framework should take them into account. For this reason, modify the generic PM domains framework so that the domain .power_off() and .power_on() callbacks are never executed for a domain containing devices with power.irq_safe set, although the .stop_device() and .start_device() callbacks are still run for them. Additionally, introduce a flag allowing the creator of a struct generic_pm_domain object to indicate that its .stop_device() and .start_device() callbacks may be run in interrupt context (might_sleep_if() triggers if that flag is not set and one of those callbacks is run in interrupt context). Signed-off-by: Rafael J. Wysocki

PM / Domains: Use power.sybsys_data to reduce overhead

2011-08-25T13:34:12Z

Currently pm_genpd_runtime_resume() has to walk the list of devices from the device's PM domain to find the corresponding device list object containing the need_restore field to check if the driver's .runtime_resume() callback should be executed for the device. This is suboptimal and can be simplified by using power.sybsys_data to store device information used by the generic PM domains code. Signed-off-by: Rafael J. Wysocki

PM / Domains: Rename argument of pm_genpd_add_subdomain()

2011-08-25T13:33:45Z

Change the name of the second argument of pm_genpd_add_subdomain() so that it is (a) shorter and (b) in agreement with the name of the second argument of pm_genpd_add_subdomain(). Signed-off-by: Rafael J. Wysocki

PM / Domains: Rename GPD_STATE_WAIT_PARENT to GPD_STATE_WAIT_MASTER

2011-08-25T13:33:45Z

Since it is now possible for a PM domain to have multiple masters instead of one parent, rename the "wait for parent" status to reflect the new situation. Signed-off-by: Rafael J. Wysocki

PM / Domains: Allow generic PM domains to have multiple masters

2011-08-25T13:33:44Z

Currently, for a given generic PM domain there may be only one parent domain (i.e. a PM domain it depends on). However, there is at least one real-life case in which there should be two parents (masters) for one PM domain (the A3RV domain on SH7372 turns out to depend on the A4LC domain and it depends on the A4R domain and the same time). For this reason, allow a PM domain to have multiple parents (masters) by introducing objects representing links between PM domains. The (logical) links between PM domains represent relationships in which one domain is a master (i.e. it is depended on) and another domain is a slave (i.e. it depends on the master) with the rule that the slave cannot be powered on if the master is not powered on and the master cannot be powered off if the slave is not powered off. Each struct generic_pm_domain object representing a PM domain has two lists of links, a list of links in which it is a master and a list of links in which it is a slave. The first of these lists replaces the list of subdomains and the second one is used in place of the parent pointer. Each link is represented by struct gpd_link object containing pointers to the master and the slave and two struct list_head members allowing it to hook into two lists (the master's list of "master" links and the slave's list of "slave" links). This allows the code to get to the link from each side (either from the master or from the slave) and follow it in each direction. Signed-off-by: Rafael J. Wysocki