kernel/linux.git/drivers/base/power, branch v4.5.4

PM / Domains: Fix removal of a subdomain

2016-05-04T21:49:11+00:00

commit beda5fc1ff9b527059290a97b672d2ee0eb7b92f upstream. Commit 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing) added a test to ensure that a subdomain is not a master to another subdomain or if any devices are using the subdomain before removing. This change incorrectly used the "slave_links" list to determine if the subdomain is a master to another subdomain, where it should have been using the "master_links" list instead. The "slave_links" list will never be empty for a subdomain and so a subdomain can never be removed. Fix this by testing if the "master_links" list is empty instead. Fixes: 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing) Signed-off-by: Jon Hunter Reviewed-by: Thierry Reding Acked-by: Ulf Hansson Acked-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / OPP: Initialize u_volt_min/max to a valid value

2016-05-04T21:49:11+00:00

commit c88c395f4a6485f23f81e385c79945d68bcd5c5d upstream. We kept u_volt_min/max initialized to 0, when only the target voltage is present in DT, instead of the target/min/max triplet. This didn't go well with the regulator framework, as on few calls the min voltage was set to target and max was set to 0 and so resulted in a kernel crash like below: kernel BUG at ../drivers/regulator/core.c:216! [] (regulator_check_voltage) from [] (regulator_set_voltage_unlocked+0x58/0x230) [] (regulator_set_voltage_unlocked) from [] (regulator_set_voltage+0x28/0x54) [] (regulator_set_voltage) from [] (_set_opp_voltage+0x30/0x98) [] (_set_opp_voltage) from [] (dev_pm_opp_set_rate+0xf0/0x28c) [] (dev_pm_opp_set_rate) from [] (__cpufreq_driver_target+0x184/0x2b4) [] (__cpufreq_driver_target) from [] (dbs_check_cpu+0x1b0/0x1f4) [] (dbs_check_cpu) from [] (cpufreq_governor_dbs+0x324/0x5c4) [] (cpufreq_governor_dbs) from [] (__cpufreq_governor+0xe4/0x1ec) [] (__cpufreq_governor) from [] (cpufreq_init_policy+0x64/0x8c) [] (cpufreq_init_policy) from [] (cpufreq_online+0x2fc/0x708) [] (cpufreq_online) from [] (subsys_interface_register+0x94/0xd8) [] (subsys_interface_register) from [] (cpufreq_register_driver+0x14c/0x19c) [] (cpufreq_register_driver) from [] (dt_cpufreq_probe+0x70/0xec) [] (dt_cpufreq_probe) from [] (platform_drv_probe+0x4c/0xb0) [] (platform_drv_probe) from [] (driver_probe_device+0x214/0x2c0) [] (driver_probe_device) from [] (__driver_attach+0x8c/0x90) [] (__driver_attach) from [] (bus_for_each_dev+0x68/0x9c) [] (bus_for_each_dev) from [] (bus_add_driver+0x1a0/0x218) [] (bus_add_driver) from [] (driver_register+0x78/0xf8) [] (driver_register) from [] (do_one_initcall+0x90/0x1d8) [] (do_one_initcall) from [] (kernel_init_freeable+0x15c/0x1fc) [] (kernel_init_freeable) from [] (kernel_init+0x8/0xf0) [] (kernel_init) from [] (ret_from_fork+0x14/0x3c) Code: e1550004 baffffeb e3a00000 e8bd8070 (e7f001f2) Fix that by initializing u_volt_min/max to the target voltage in such cases. Reported-and-tested-by: Krzysztof Kozlowski Fixes: 274659029c9d (PM / OPP: Add support to parse "operating-points-v2" bindings) Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

Merge branches 'pm-core' and 'pm-domains'

2016-02-05T23:34:01+00:00

* pm-core: PM: Avoid false-positive warnings in dev_pm_domain_set() ACPI / LPSS: set PM domain via helper setter * pm-domains: PM / Domains: Silence compiler warning for an unused function

PM: Avoid false-positive warnings in dev_pm_domain_set()

2016-02-03T18:10:37+00:00

There is a WARN_ON() in dev_pm_domain_set() that triggers on attempts to set the pm_domain pointer for devices with a driver bound. However, that WARN_ON() triggers on attempts to clear the pointer too and the test it uses is based on checking the device's p->knode_driver pointer which still is set when the device bus type's/driver's ->remove callback has been executed. This leads to false-positive warnings when bus type code calls dev_pm_domain_set() to clear the pm_domain pointer after invoking the driver's ->remove() callback. To avoid those false-positives, make dev_pm_domain_set() check if the pointer passed to it is NULL and skip the warning in that case. Fixes: 989561de9b51 (PM / Domains: add setter for dev.pm_domain) Signed-off-by: Rafael J. Wysocki Tested-by: Andy Shevchenko Tested-by: Sinan Kaya Tested-by: Steven Rostedt Acked-by: Ulf Hansson

PM / Domains: Silence compiler warning for an unused function

2016-02-03T00:24:36+00:00

The only remaining caller of genpd_poweron() is conditionally compiled based on CONFIG_PM_GENERIC_DOMAINS_OF, so we get a warning when that is unset. By moving the locking/unlocking of the genpd outside genpd_poweron(), thus to the caller, genpd_poweron() becomes redundant. Within this context let's then rename the wrapper function, __genpd_poweron(), to genpd_poweron() as it will then be consistent with its friend genpd_poweroff(). This change silence the warning about the unused function. Reported-by: Arnd Bergmann Fixes: ea823c7cbffa "PM / Domains: Remove pm_genpd_poweron() API" Signed-off-by: Ulf Hansson Acked-by: Arnd Bergmann Cc: 4.4+ # 4.4+ Signed-off-by: Rafael J. Wysocki

Merge branches 'pm-cpuidle', 'pm-cpufreq', 'pm-domains' and 'pm-sleep'

2016-01-29T20:45:17+00:00

* pm-cpuidle: cpuidle: coupled: remove unused define cpuidle_coupled_lock cpuidle: fix fallback mechanism for suspend to idle in absence of enter_freeze * pm-cpufreq: cpufreq: cpufreq-dt: avoid uninitialized variable warnings: cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototype cpufreq: Use list_is_last() to check last entry of the policy list cpufreq: Fix NULL reference crash while accessing policy->governor_data * pm-domains: PM / Domains: Fix typo in comment PM / Domains: Fix potential deadlock while adding/removing subdomains PM / domains: fix lockdep issue for all subdomains * pm-sleep: PM: APM_EMULATION does not depend on PM

PM / Domains: Fix typo in comment

2016-01-27T22:07:29+00:00

Acked-by: Kevin Hilman Signed-off-by: Moritz Fischer Signed-off-by: Rafael J. Wysocki

PM / Domains: Fix potential deadlock while adding/removing subdomains

2016-01-27T22:01:25+00:00

We must preserve the same order of how we acquire and release the lock for genpd, as otherwise we may encounter deadlocks. The power on phase of a genpd starts by acquiring its lock. Then it walks the hierarchy of its parent domains to be able to power on these first, as per design of genpd. From a locking perspective this means the locks of the parents becomes acquired after the lock of the subdomain. Let's fix pm_genpd_add|remove_subdomain() to maintain the same order of acquiring/releasing the genpd lock as being applied in the power on/off sequence. Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

PM / domains: fix lockdep issue for all subdomains

2016-01-22T01:31:32+00:00

During genpd_poweron, genpd->lock is acquired recursively for each parent (master) domain, which are separate objects. This confuses lockdep, which considers every operation on genpd->lock as being done on the same lock class. This leads to the following false positive warning: ============================================= [ INFO: possible recursive locking detected ] 4.4.0-rc4-xu3s #32 Not tainted --------------------------------------------- swapper/0/1 is trying to acquire lock: (&genpd->lock){+.+...}, at: [] __genpd_poweron+0x64/0x108 but task is already holding lock: (&genpd->lock){+.+...}, at: [] genpd_dev_pm_attach+0x168/0x1b8 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&genpd->lock); lock(&genpd->lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by swapper/0/1: #0: (&dev->mutex){......}, at: [] __driver_attach+0x48/0x98 #1: (&dev->mutex){......}, at: [] __driver_attach+0x58/0x98 #2: (&genpd->lock){+.+...}, at: [] genpd_dev_pm_attach+0x168/0x1b8 stack backtrace: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.0-rc4-xu3s #32 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (dump_stack+0x84/0xc4) [] (dump_stack) from [] (__lock_acquire+0x1f88/0x215c) [] (__lock_acquire) from [] (lock_acquire+0xa4/0xd0) [] (lock_acquire) from [] (mutex_lock_nested+0x70/0x4d4) [] (mutex_lock_nested) from [] (__genpd_poweron+0x64/0x108) [] (__genpd_poweron) from [] (genpd_dev_pm_attach+0x170/0x1b8) [] (genpd_dev_pm_attach) from [] (platform_drv_probe+0x2c/0xac) [] (platform_drv_probe) from [] (driver_probe_device+0x208/0x2fc) [] (driver_probe_device) from [] (__driver_attach+0x94/0x98) [] (__driver_attach) from [] (bus_for_each_dev+0x68/0x9c) [] (bus_for_each_dev) from [] (bus_add_driver+0x1a0/0x218) [] (bus_add_driver) from [] (driver_register+0x78/0xf8) [] (driver_register) from [] (exynos_drm_register_drivers+0x28/0x74) [] (exynos_drm_register_drivers) from [] (exynos_drm_init+0x6c/0xc4) [] (exynos_drm_init) from [] (do_one_initcall+0x90/0x1dc) [] (do_one_initcall) from [] (kernel_init_freeable+0x158/0x1f8) [] (kernel_init_freeable) from [] (kernel_init+0x8/0xe8) [] (kernel_init) from [] (ret_from_fork+0x14/0x24) This patch replaces mutex_lock with mutex_lock_nested() and uses recursion depth to annotate each genpd->lock operation with separate lockdep subclass. Reported-by: Anand Moon Signed-off-by: Marek Szyprowski Tested-by: Anand Moon Tested-by: Tobias Jakobi Acked-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-core'

2016-01-20T23:42:59+00:00

* pm-core: driver core: Avoid NULL pointer dereferences in device_is_bound() platform: Do not detach from PM domains on shutdown USB / PM: Allow USB devices to remain runtime-suspended when sleeping PM / sleep: Go direct_complete if driver has no callbacks PM / Domains: add setter for dev.pm_domain device core: add device_is_bound()