From: Matthias Kaehlcke The Power Management code uses semaphores as mutexes. Use the mutex API instead of the (binary) semaphores. Signed-off-by: Matthias Kaehlcke Signed-off-by: Andrew Morton --- drivers/base/power/main.c | 14 ++++++++------ drivers/base/power/power.h | 4 ++-- drivers/base/power/resume.c | 12 ++++++------ drivers/base/power/runtime.c | 12 ++++++------ drivers/base/power/suspend.c | 14 +++++++------- 5 files changed, 29 insertions(+), 27 deletions(-) diff -puN drivers/base/power/main.c~power-management-use-mutexes-instead-of-semaphores drivers/base/power/main.c --- a/drivers/base/power/main.c~power-management-use-mutexes-instead-of-semaphores +++ a/drivers/base/power/main.c @@ -20,14 +20,16 @@ */ #include +#include + #include "power.h" LIST_HEAD(dpm_active); LIST_HEAD(dpm_off); LIST_HEAD(dpm_off_irq); -DECLARE_MUTEX(dpm_sem); -DECLARE_MUTEX(dpm_list_sem); +DEFINE_MUTEX(dpm_mtx); +DEFINE_MUTEX(dpm_list_mtx); int (*platform_enable_wakeup)(struct device *dev, int is_on); @@ -59,12 +61,12 @@ int device_pm_add(struct device * dev) pr_debug("PM: Adding info for %s:%s\n", dev->bus ? dev->bus->name : "No Bus", kobject_name(&dev->kobj)); - down(&dpm_list_sem); + mutex_lock(&dpm_list_mtx); list_add_tail(&dev->power.entry, &dpm_active); device_pm_set_parent(dev, dev->parent); if ((error = dpm_sysfs_add(dev))) list_del(&dev->power.entry); - up(&dpm_list_sem); + mutex_unlock(&dpm_list_mtx); return error; } @@ -73,11 +75,11 @@ void device_pm_remove(struct device * de pr_debug("PM: Removing info for %s:%s\n", dev->bus ? dev->bus->name : "No Bus", kobject_name(&dev->kobj)); - down(&dpm_list_sem); + mutex_lock(&dpm_list_mtx); dpm_sysfs_remove(dev); put_device(dev->power.pm_parent); list_del_init(&dev->power.entry); - up(&dpm_list_sem); + mutex_unlock(&dpm_list_mtx); } diff -puN drivers/base/power/power.h~power-management-use-mutexes-instead-of-semaphores drivers/base/power/power.h --- a/drivers/base/power/power.h~power-management-use-mutexes-instead-of-semaphores +++ a/drivers/base/power/power.h @@ -14,12 +14,12 @@ extern void device_shutdown(void); /* * Used to synchronize global power management operations. */ -extern struct semaphore dpm_sem; +extern struct mutex dpm_mtx; /* * Used to serialize changes to the dpm_* lists. */ -extern struct semaphore dpm_list_sem; +extern struct mutex dpm_list_mtx; /* * The PM lists. diff -puN drivers/base/power/resume.c~power-management-use-mutexes-instead-of-semaphores drivers/base/power/resume.c --- a/drivers/base/power/resume.c~power-management-use-mutexes-instead-of-semaphores +++ a/drivers/base/power/resume.c @@ -80,7 +80,7 @@ static int resume_device_early(struct de */ void dpm_resume(void) { - down(&dpm_list_sem); + mutex_lock(&dpm_list_mtx); while(!list_empty(&dpm_off)) { struct list_head * entry = dpm_off.next; struct device * dev = to_device(entry); @@ -88,13 +88,13 @@ void dpm_resume(void) get_device(dev); list_move_tail(entry, &dpm_active); - up(&dpm_list_sem); + mutex_unlock(&dpm_list_mtx); if (!dev->power.prev_state.event) resume_device(dev); - down(&dpm_list_sem); + mutex_lock(&dpm_list_mtx); put_device(dev); } - up(&dpm_list_sem); + mutex_unlock(&dpm_list_mtx); } @@ -108,9 +108,9 @@ void dpm_resume(void) void device_resume(void) { might_sleep(); - down(&dpm_sem); + mutex_lock(&dpm_mtx); dpm_resume(); - up(&dpm_sem); + mutex_unlock(&dpm_mtx); } EXPORT_SYMBOL_GPL(device_resume); diff -puN drivers/base/power/runtime.c~power-management-use-mutexes-instead-of-semaphores drivers/base/power/runtime.c --- a/drivers/base/power/runtime.c~power-management-use-mutexes-instead-of-semaphores +++ a/drivers/base/power/runtime.c @@ -32,9 +32,9 @@ static void runtime_resume(struct device void dpm_runtime_resume(struct device * dev) { - down(&dpm_sem); + mutex_lock(&dpm_mtx); runtime_resume(dev); - up(&dpm_sem); + mutex_unlock(&dpm_mtx); } EXPORT_SYMBOL(dpm_runtime_resume); @@ -49,7 +49,7 @@ int dpm_runtime_suspend(struct device * { int error = 0; - down(&dpm_sem); + mutex_lock(&dpm_mtx); if (dev->power.power_state.event == state.event) goto Done; @@ -59,7 +59,7 @@ int dpm_runtime_suspend(struct device * if (!(error = suspend_device(dev, state))) dev->power.power_state = state; Done: - up(&dpm_sem); + mutex_unlock(&dpm_mtx); return error; } EXPORT_SYMBOL(dpm_runtime_suspend); @@ -78,8 +78,8 @@ EXPORT_SYMBOL(dpm_runtime_suspend); */ void dpm_set_power_state(struct device * dev, pm_message_t state) { - down(&dpm_sem); + mutex_lock(&dpm_mtx); dev->power.power_state = state; - up(&dpm_sem); + mutex_unlock(&dpm_mtx); } #endif /* 0 */ diff -puN drivers/base/power/suspend.c~power-management-use-mutexes-instead-of-semaphores drivers/base/power/suspend.c --- a/drivers/base/power/suspend.c~power-management-use-mutexes-instead-of-semaphores +++ a/drivers/base/power/suspend.c @@ -108,7 +108,7 @@ int suspend_device(struct device * dev, /* * This is called with interrupts off, only a single CPU - * running. We can't do down() on a semaphore (and we don't + * running. We can't acquire a mutex or semaphore (and we don't * need the protection) */ static int suspend_device_late(struct device *dev, pm_message_t state) @@ -153,18 +153,18 @@ int device_suspend(pm_message_t state) int error = 0; might_sleep(); - down(&dpm_sem); - down(&dpm_list_sem); + mutex_lock(&dpm_mtx); + mutex_lock(&dpm_list_mtx); while (!list_empty(&dpm_active) && error == 0) { struct list_head * entry = dpm_active.prev; struct device * dev = to_device(entry); get_device(dev); - up(&dpm_list_sem); + mutex_unlock(&dpm_list_mtx); error = suspend_device(dev, state); - down(&dpm_list_sem); + mutex_lock(&dpm_list_mtx); /* Check if the device got removed */ if (!list_empty(&dev->power.entry)) { @@ -179,11 +179,11 @@ int device_suspend(pm_message_t state) error == -EAGAIN ? " (please convert to suspend_late)" : ""); put_device(dev); } - up(&dpm_list_sem); + mutex_unlock(&dpm_list_mtx); if (error) dpm_resume(); - up(&dpm_sem); + mutex_unlock(&dpm_mtx); return error; } _