- 根目录:
- drivers
- base
- power
- domain.c
/*
* drivers/base/power/domain.c - Common code related to device power domains.
*
* Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
*
* This file is released under the GPLv2.
*/
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
#include <linux/pm_qos.h>
#include <linux/pm_clock.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/suspend.h>
#include <linux/export.h>
#define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \
({ \
type (*__routine)(struct device *__d); \
type __ret = (type)0; \
\
__routine = genpd->dev_ops.callback; \
if (__routine) { \
__ret = __routine(dev); \
} \
__ret; \
})
#define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name) \
({ \
ktime_t __start = ktime_get(); \
type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \
s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \
struct gpd_timing_data *__td = &dev_gpd_data(dev)->td; \
if (!__retval && __elapsed > __td->field) { \
__td->field = __elapsed; \
dev_dbg(dev, name " latency exceeded, new value %lld ns\n", \
__elapsed); \
genpd->max_off_time_changed = true; \
__td->constraint_changed = true; \
} \
__retval; \
})
static LIST_HEAD(gpd_list);
static DEFINE_MUTEX(gpd_list_lock);
static struct generic_pm_domain *pm_genpd_lookup_name(const char *domain_name)
{
struct generic_pm_domain *genpd = NULL, *gpd;
if (IS_ERR_OR_NULL(domain_name))
return NULL;
mutex_lock(&gpd_list_lock);
list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
if (!strcmp(gpd->name, domain_name)) {
genpd = gpd;
break;
}
}
mutex_unlock(&gpd_list_lock);
return genpd;
}
/*
* Get the generic PM domain for a particular struct device.
* This validates the struct device pointer, the PM domain pointer,
* and checks that the PM domain pointer is a real generic PM domain.
* Any failure results in NULL being returned.
*/
struct generic_pm_domain *pm_genpd_lookup_dev(struct device *dev)
{
struct generic_pm_domain *genpd = NULL, *gpd;
if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
return NULL;
mutex_lock(&gpd_list_lock);
list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
if (&gpd->domain == dev->pm_domain) {
genpd = gpd;
break;
}
}
mutex_unlock(&gpd_list_lock);
return genpd;
}
/*
* This should only be used where we are certain that the pm_domain
* attached to the device is a genpd domain.
*/
static struct generic_pm_domain *dev_to_genpd(struct device *dev)
{
if (IS_ERR_OR_NULL(dev->pm_domain))
return ERR_PTR(-EINVAL);
return pd_to_genpd(dev->pm_domain);
}
static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
{
return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev,
stop_latency_ns, "stop");
}
static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
{
return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev,
start_latency_ns, "start");
}
static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
{
bool ret = false;
if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
ret = !!atomic_dec_and_test(&genpd->sd_count);
return ret;
}
static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
{
atomic_inc(&genpd->sd_count);
smp_mb__after_atomic();
}
static void genpd_acquire_lock(struct generic_pm_domain *genpd)
{
DEFINE_WAIT(wait);
mutex_lock(&genpd->lock);
/*
* Wait for the domain to transition into either the active,
* or the power off state.
*/
for (;;) {
prepare_to_wait(&genpd->status_wait_queue, &wait,
TASK_UNINTERRUPTIBLE);
if (genpd->status == GPD_STATE_ACTIVE
|| genpd->status == GPD_STATE_POWER_OFF)
break;
mutex_unlock(&genpd->lock);
schedule();
mutex_lock(&genpd->lock);
}
finish_wait(&genpd->status_wait_queue, &wait);
}
static void genpd_release_lock(struct generic_pm_domain *genpd)
{
mutex_unlock(&genpd->lock);
}
static void genpd_set_active(struct generic_pm_domain *genpd)
{
if (genpd->resume_count == 0)
genpd->status = GPD_STATE_ACTIVE;
}
static void genpd_recalc_cpu_exit_latency(struct generic_pm_domain *genpd)
{
s64 usecs64;
if (!genpd->cpuidle_data)
return;
usecs64 = genpd->power_on_latency_ns;
do_div(usecs64, NSEC_PER_USEC);
usecs64 += genpd->cpuidle_data->saved_exit_latency;
genpd->cpuidle_data->idle_state->exit_latency = usecs64;
}
static int genpd_power_on(struct generic_pm_domain *genpd)
{
ktime_t time_start;
s64 elapsed_ns;
int ret;
if (!genpd->power_on)
return 0;
time_start = ktime_get();
ret = genpd->power_on(genpd);
if (ret)
return ret;
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
if (elapsed_ns <= genpd->power_on_latency_ns)
return ret;
genpd->power_on_latency_ns = elapsed_ns;
genpd->max_off_time_changed = true;
genpd_recalc_cpu_exit_latency(genpd);
pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
genpd->name, "on", elapsed_ns);
return ret;
}
static int genpd_power_off(struct generic_pm_domain *genpd)
{
ktime_t time_start;
s64 elapsed_ns;
int ret;
if (!genpd->power_off)
return 0;
time_start = ktime_get();
ret = genpd->power_off(genpd);
if (ret == -EBUSY)
return ret;
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
if (elapsed_ns <= genpd->power_off_latency_ns)
return ret;
genpd->power_off_latency_ns = elapsed_ns;
genpd->max_off_time_changed = true;
pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
genpd->name, "off", elapsed_ns);
return ret;
}
/**
* __pm_genpd_poweron - Restore power to a given PM domain and its masters.
* @genpd: PM domain to power up.
*
* Restore power to @genpd and all of its masters so that it is possible to
* resume a device belonging to it.
*/
static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
__releases(&genpd->lock) __acquires(&genpd->lock)
{
struct gpd_link *link;
DEFINE_WAIT(wait);
int ret = 0;
/* If the domain's master is being waited for, we have to wait too. */
for (;;) {
prepare_to_wait(&genpd->status_wait_queue, &wait,
TASK_UNINTERRUPTIBLE);
if (genpd->status != GPD_STATE_WAIT_MASTER)
break;
mutex_unlock(&genpd->lock);
schedule();
mutex_lock(&genpd->lock);
}
finish_wait(&genpd->status_wait_queue, &wait);
if (genpd->status == GPD_STATE_ACTIVE
|| (genpd->prepared_count > 0 && genpd->suspend_power_off))
return 0;
if (genpd->status != GPD_STATE_POWER_OFF) {
genpd_set_active(genpd);
return 0;
}
if (genpd->cpuidle_data) {
cpuidle_pause_and_lock();
genpd->cpuidle_data->idle_state->disabled = true;
cpuidle_resume_and_unlock();
goto out;
}
/*
* The list is guaranteed not to change while the loop below is being
* executed, unless one of the masters' .power_on() callbacks fiddles
* with it.
*/
list_for_each_entry(link, &genpd->slave_links, slave_node) {
genpd_sd_counter_inc(link->master);
genpd->status = GPD_STATE_WAIT_MASTER;
mutex_unlock(&genpd->lock);
ret = pm_genpd_poweron(link->master);
mutex_lock(&genpd->lock);
/*
* The "wait for parent" status is guaranteed not to change
* while the master is powering on.
*/
genpd->status = GPD_STATE_POWER_OFF;
wake_up_all(&genpd->status_wait_queue);
if (ret) {
genpd_sd_counter_dec(link->master);
goto err;
}
}
ret = genpd_power_on(genpd);
if (ret)
goto err;
out:
genpd_set_active(genpd);
return 0;
err:
list_for_each_entry_continue_reverse(link, &genpd->slave_links, slave_node)
genpd_sd_counter_dec(link->master);
return ret;
}
/**
* pm_genpd_poweron - Restore power to a given PM domain and its masters.
* @genpd: PM domain to power up.
*/
int pm_genpd_poweron(struct generic_pm_domain *genpd)
{
int ret;
mutex_lock(&genpd->lock);
ret = __pm_genpd_poweron(genpd);
mutex_unlock(&genpd->lock);
return ret;
}
/**
* pm_genpd_name_poweron - Restore power to a given PM domain and its masters.
* @domain_name: Name of the PM domain to power up.
*/
int pm_genpd_name_poweron(const char *domain_name)
{
struct generic_pm_domain *genpd;
genpd = pm_genpd_lookup_name(domain_name);
return genpd ? pm_genpd_poweron(genpd) : -EINVAL;
}
static int genpd_start_dev_no_timing(struct generic_pm_domain *genpd,
struct device *dev)
{
return GENPD_DEV_CALLBACK(genpd, int, start, dev);
}
static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
{
return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev,
save_state_latency_ns, "state save");
}
static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev)
{
return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev,
restore_state_latency_ns,
"state restore");
}
static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
unsigned long val, void *ptr)
{
struct generic_pm_domain_data *gpd_data;
struct device *dev;
gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
dev = gpd_data->base.dev;
for (;;) {
struct generic_pm_domain *genpd;
struct pm_domain_data *pdd;
spin_lock_irq(&dev->power.lock);
pdd = dev->power.subsys_data ?
dev->power.subsys_data->domain_data : NULL;
if (pdd && pdd->dev) {
to_gpd_data(pdd)->td.constraint_changed = true;
genpd = dev_to_genpd(dev);
} else {
genpd = ERR_PTR(-ENODATA);
}
spin_unlock_irq(&dev->power.lock);
if (!IS_ERR(genpd)) {
mutex_lock(&genpd->lock);
genpd->max_off_time_changed = true;
mutex_unlock(&genpd->lock);
}
dev = dev->parent;
if (!dev || dev->power.ignore_children)
break;
}
return NOTIFY_DONE;
}
/**
* __pm_genpd_save_device - Save the pre-suspend state of a device.
* @pdd: Domain data of the device to save the state of.
* @genpd: PM domain the device belongs to.
*/
static int __pm_genpd_save_device(struct pm_domain_data *pdd,
struct generic_pm_domain *genpd)
__releases(&genpd->lock) __acquires(&genpd->lock)
{
struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
struct device *dev = pdd->dev;
int ret = 0;
if (gpd_data->need_restore > 0)
return 0;
/*
* If the value of the need_restore flag is still unknown at this point,
* we trust that pm_genpd_poweroff() has verified that the device is
* already runtime PM suspended.
*/
if (gpd_data->need_restore < 0) {
gpd_data->need_restore = 1;
return 0;
}
mutex_unlock(&genpd->lock);
genpd_start_dev(genpd, dev);
ret = genpd_save_dev(genpd, dev);
genpd_stop_dev(genpd, dev);
mutex_lock(&genpd->lock);
if (!ret)
gpd_data->need_restore = 1;
return ret;
}
/**
* __pm_genpd_restore_device - Restore the pre-suspend state of a device.
* @pdd: Domain data of the device to restore the state of.
* @genpd: PM domain the device belongs to.
*/
static void __pm_genpd_restore_device(struct pm_domain_data *pdd,
struct generic_pm_domain *genpd)
__releases(&genpd->lock) __acquires(&genpd->lock)
{
struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
struct device *dev = pdd->dev;
int need_restore = gpd_data->need_restore;
gpd_data->need_restore = 0;
mutex_unlock(&genpd->lock);
genpd_start_dev(genpd, dev);
/*
* Call genpd_restore_dev() for recently added devices too (need_restore
* is negative then).
*/
if (need_restore)
genpd_restore_dev(genpd, dev);
mutex_lock(&genpd->lock);
}
/**
* genpd_abort_poweroff - Check if a PM domain power off should be aborted.
* @genpd: PM domain to check.
*
* Return true if a PM domain's status changed to GPD_STATE_ACTIVE during
* a "power off" operation, which means that a "power on" has occured in the
* meantime, or if its resume_count field is different from zero, which means
* that one of its devices has been resumed in the meantime.
*/
static bool genpd_abort_poweroff(struct generic_pm_domain *genpd)
{
return genpd->status == GPD_STATE_WAIT_MASTER
|| genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0;
}
/**
* genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
* @genpd: PM domait to power off.
*
* Queue up the execution of pm_genpd_poweroff() unless it's already been done
* before.
*/
static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
{
queue_work(pm_wq, &genpd->power_off_work);
}
/**
* pm_genpd_poweroff - Remove power from a given PM domain.
* @genpd: PM domain to power down.
*
* If all of the @genpd's devices have been suspended and all of its subdomains
* have been powered down, run the runtime suspend callbacks provided by all of
* the @genpd's devices' drivers and remove power from @genpd.
*/
static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
__releases(&genpd->lock) __acquires(&genpd->lock)
{
struct pm_domain_data *pdd;
struct gpd_link *link;
unsigned int not_suspended;
int ret = 0;
start:
/*
* Do not try to power off the domain in the following situations:
* (1) The domain is already in the "power off" state.
* (2) The domain is waiting for its master to power up.
* (3) One of the domain's devices is being resumed right now.
* (4) System suspend is in progress.
*/
if (genpd->status == GPD_STATE_POWER_OFF
|| genpd->status == GPD_STATE_WAIT_MASTER
|| genpd->resume_count > 0 || genpd->prepared_count > 0)
return 0;
if (atomic_read(&genpd->sd_count) > 0)
return -EBUSY;
not_suspended = 0;
list_for_each_entry(pdd, &genpd->dev_list, list_node) {
enum pm_qos_flags_status stat;
stat = dev_pm_qos_flags(pdd->dev,
PM_QOS_FLAG_NO_POWER_OFF
| PM_QOS_FLAG_REMOTE_WAKEUP);
if (stat > PM_QOS_FLAGS_NONE)
return -EBUSY;
if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
|| pdd->dev->power.irq_safe))
not_suspended++;
}
if (not_suspended > genpd->in_progress)
return -EBUSY;
if (genpd->poweroff_task) {
/*
* Another instance of pm_genpd_poweroff() is executing
* callbacks, so tell it to start over and return.
*/
genpd->status = GPD_STATE_REPEAT;
return 0;
}
if (genpd->gov && genpd->gov->power_down_ok) {
if (!genpd->gov->power_down_ok(&genpd->domain))
return -EAGAIN;
}
genpd->status = GPD_STATE_BUSY;
genpd->poweroff_task = current;
list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) {
ret = atomic_read(&genpd->sd_count) == 0 ?
__pm_genpd_save_device(pdd, genpd) : -EBUSY;
if (genpd_abort_poweroff(genpd))
goto out;
if (ret) {
genpd_set_active(genpd);
goto out;
}
if (genpd->status == GPD_STATE_REPEAT) {
genpd->poweroff_task = NULL;
goto start;
}
}
if (genpd->cpuidle_data) {
/*
* If cpuidle_data is set, cpuidle should turn the domain off
* when the CPU in it is idle. In that case we don't decrement
* the subdomain counts of the master domains, so that power is
* not removed from the current domain prematurely as a result
* of cutting off the masters' power.
*/
genpd->status = GPD_STATE_POWER_OFF;
cpuidle_pause_and_lock();
genpd->cpuidle_data->idle_state->disabled = false;
cpuidle_resume_and_unlock();
goto out;
}
if (genpd->power_off) {
if (atomic_read(&genpd->sd_count) > 0) {
ret = -EBUSY;
goto out;
}
/*
* If sd_count > 0 at this point, one of the subdomains hasn't
* managed to call pm_genpd_poweron() for the master yet after
* incrementing it. In that case pm_genpd_poweron() will wait
* for us to drop the lock, so we can call .power_off() and let
* the pm_genpd_poweron() restore power for us (this shouldn't
* happen very often).
*/
ret = genpd_power_off(genpd);
if (ret == -EBUSY) {
genpd_set_active(genpd);
goto out;
}
}
genpd->status = GPD_STATE_POWER_OFF;
list_for_each_entry(link, &genpd->slave_links, slave_node) {
genpd_sd_counter_dec(link->master);
genpd_queue_power_off_work(link->master);
}
out:
genpd->poweroff_task = NULL;
wake_up_all(&genpd->status_wait_queue);
return ret;
}
/**
* genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
* @work: Work structure used for scheduling the execution of this function.
*/
static void genpd_power_off_work_fn(struct work_struct *work)
{
struct generic_pm_domain *genpd;
genpd = container_of(work, struct generic_pm_domain, power_off_work);
genpd_acquire_lock(genpd);
pm_genpd_poweroff(genpd);
genpd_release_lock(genpd);
}
/**
* pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
* @dev: Device to suspend.
*
* Carry out a runtime suspend of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a PM domain consisting of I/O devices.
*/
static int pm_genpd_runtime_suspend(struct device *dev)
{
struct generic_pm_domain *genpd;
struct generic_pm_domain_data *gpd_data;
bool (*stop_ok)(struct device *__dev);
int ret;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
if (stop_ok && !stop_ok(dev))
return -EBUSY;
ret = genpd_stop_dev(genpd, dev);
if (ret)
return ret;
/*
* If power.irq_safe is set, this routine will be run with interrupts
* off, so it can't use mutexes.
*/
if (dev->power.irq_safe)
return 0;
mutex_lock(&genpd->lock);
/*
* If we have an unknown state of the need_restore flag, it means none
* of the runtime PM callbacks has been invoked yet. Let's update the
* flag to reflect that the current state is active.
*/
gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
if (gpd_data->need_restore < 0)
gpd_data->need_restore = 0;
genpd->in_progress++;
pm_genpd_poweroff(genpd);
genpd->in_progress--;
mutex_unlock(&genpd->lock);
return 0;
}
/**
* pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
* @dev: Device to resume.
*
* Carry out a runtime resume of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a PM domain consisting of I/O devices.
*/
static int pm_genpd_runtime_resume(struct device *dev)
{
struct generic_pm_domain *genpd;
DEFINE_WAIT(wait);
int ret;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
/* If power.irq_safe, the PM domain is never powered off. */
if (dev->power.irq_safe)
return genpd_start_dev_no_timing(genpd, dev);
mutex_lock(&genpd->lock);
ret = __pm_genpd_poweron(genpd);
if (ret) {
mutex_unlock(&genpd->lock);
return ret;
}
genpd->status = GPD_STATE_BUSY;
genpd->resume_count++;
for (;;) {
prepare_to_wait(&genpd->status_wait_queue, &wait,
TASK_UNINTERRUPTIBLE);
/*
* If current is the powering off task, we have been called
* reentrantly from one of the device callbacks, so we should
* not wait.
*/
if (!genpd->poweroff_task || genpd->poweroff_task == current)
break;
mutex_unlock(&genpd->lock);
schedule();
mutex_lock(&genpd->lock);
}
finish_wait(&genpd->status_wait_queue, &wait);
__pm_genpd_restore_device(dev->power.subsys_data->domain_data, genpd);
genpd->resume_count--;
genpd_set_active(genpd);
wake_up_all(&genpd->status_wait_queue);
mutex_unlock(&genpd->lock);
return 0;
}
static bool pd_ignore_unused;
static int __init pd_ignore_unused_setup(char *__unused)
{
pd_ignore_unused = true;
return 1;
}
__setup("pd_ignore_unused", pd_ignore_unused_setup);
/**
* pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
*/
void pm_genpd_poweroff_unused(void)
{
struct generic_pm_domain *genpd;
if (pd_ignore_unused) {
pr_warn("genpd: Not disabling unused power domains\n");
return;
}
mutex_lock(&gpd_list_lock);
list_for_each_entry(genpd, &gpd_list, gpd_list_node)
genpd_queue_power_off_work(genpd);
mutex_unlock(&gpd_list_lock);
}
static int __init genpd_poweroff_unused(void)
{
pm_genpd_poweroff_unused();
return 0;
}
late_initcall(genpd_poweroff_unused);
#ifdef CONFIG_PM_SLEEP
/**
* pm_genpd_present - Check if the given PM domain has been initialized.
* @genpd: PM domain to check.
*/
static bool pm_genpd_present(const struct generic_pm_domain *genpd)
{
const struct generic_pm_domain *gpd;
if (IS_ERR_OR_NULL(genpd))
return false;
list_for_each_entry(gpd, &gpd_list, gpd_list_node)
if (gpd == genpd)
return true;
return false;
}
static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
struct device *dev)
{
return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
}
/**
* pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
* @genpd: PM domain to power off, if possible.
*
* Check if the given PM domain can be powered off (during system suspend or
* hibernation) and do that if so. Also, in that case propagate to its masters.
*
* This function is only called in "noirq" and "syscore" stages of system power
* transitions, so it need not acquire locks (all of the "noirq" callbacks are
* executed sequentially, so it is guaranteed that it will never run twice in
* parallel).
*/
static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
{
struct gpd_link *link;
if (genpd->status == GPD_STATE_POWER_OFF)
return;
if (genpd->suspended_count != genpd->device_count
|| atomic_read(&genpd->sd_count) > 0)
return;
genpd_power_off(genpd);
genpd->status = GPD_STATE_POWER_OFF;
list_for_each_entry(link, &genpd->slave_links, slave_node) {
genpd_sd_counter_dec(link->master);
pm_genpd_sync_poweroff(link->master);
}
}
/**
* pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
* @genpd: PM domain to power on.
*
* This function is only called in "noirq" and "syscore" stages of system power
* transitions, so it need not acquire locks (all of the "noirq" callbacks are
* executed sequentially, so it is guaranteed that it will never run twice in
* parallel).
*/
static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd)
{
struct gpd_link *link;
if (genpd->status != GPD_STATE_POWER_OFF)
return;
list_for_each_entry(link, &genpd->slave_links, slave_node) {
pm_genpd_sync_poweron(link->master);
genpd_sd_counter_inc(link->master);
}
genpd_power_on(genpd);
genpd->status = GPD_STATE_ACTIVE;
}
/**
* resume_needed - Check whether to resume a device before system suspend.
* @dev: Device to check.
* @genpd: PM domain the device belongs to.
*
* There are two cases in which a device that can wake up the system from sleep
* states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
* to wake up the system and it has to remain active for this purpose while the
* system is in the sleep state and (2) if the device is not enabled to wake up
* the system from sleep states and it generally doesn't generate wakeup signals
* by itself (those signals are generated on its behalf by other parts of the
* system). In the latter case it may be necessary to reconfigure the device's
* wakeup settings during system suspend, because it may have been set up to
* signal remote wakeup from the system's working state as needed by runtime PM.
* Return 'true' in either of the above cases.
*/
static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
{
bool active_wakeup;
if (!device_can_wakeup(dev))
return false;
active_wakeup = genpd_dev_active_wakeup(genpd, dev);
return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
}
/**
* pm_genpd_prepare - Start power transition of a device in a PM domain.
* @dev: Device to start the transition of.
*
* Start a power transition of a device (during a system-wide power transition)
* under the assumption that its pm_domain field points to the domain member of
* an object of type struct generic_pm_domain representing a PM domain
* consisting of I/O devices.
*/
static int pm_genpd_prepare(struct device *dev)
{
struct generic_pm_domain *genpd;
int ret;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
/*
* If a wakeup request is pending for the device, it should be woken up
* at this point and a system wakeup event should be reported if it's
* set up to wake up the system from sleep states.
*/
pm_runtime_get_noresume(dev);
if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
pm_wakeup_event(dev, 0);
if (pm_wakeup_pending()) {
pm_runtime_put(dev);
return -EBUSY;
}
if (resume_needed(dev, genpd))
pm_runtime_resume(dev);
genpd_acquire_lock(genpd);
if (genpd->prepared_count++ == 0) {
genpd->suspended_count = 0;
genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
}
genpd_release_lock(genpd);
if (genpd->suspend_power_off) {
pm_runtime_put_noidle(dev);
return 0;
}
/*
* The PM domain must be in the GPD_STATE_ACTIVE state at this point,
* so pm_genpd_poweron() will return immediately, but if the device
* is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
* to make it operational.
*/
pm_runtime_resume(dev);
__pm_runtime_disable(dev, false);
ret = pm_generic_prepare(dev);
if (ret) {
mutex_lock(&genpd->lock);
if (--genpd->prepared_count == 0)
genpd->suspend_power_off = false;
mutex_unlock(&genpd->lock);
pm_runtime_enable(dev);
}
pm_runtime_put(dev);
return ret;
}
/**
* pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
* @dev: Device to suspend.
*
* Suspend a device under the assumption that its pm_domain field points to the
* domain member of an object of type struct generic_pm_domain representing
* a PM domain consisting of I/O devices.
*/
static int pm_genpd_suspend(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
}
/**
* pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
* @dev: Device to suspend.
*
* Carry out a late suspend of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a PM domain consisting of I/O devices.
*/
static int pm_genpd_suspend_late(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_suspend_late(dev);
}
/**
* pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
* @dev: Device to suspend.
*
* Stop the device and remove power from the domain if all devices in it have
* been stopped.
*/
static int pm_genpd_suspend_noirq(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
if (genpd->suspend_power_off
|| (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
return 0;
genpd_stop_dev(genpd, dev);
/*
* Since all of the "noirq" callbacks are executed sequentially, it is
* guaranteed that this function will never run twice in parallel for
* the same PM domain, so it is not necessary to use locking here.
*/
genpd->suspended_count++;
pm_genpd_sync_poweroff(genpd);
return 0;
}
/**
* pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
* @dev: Device to resume.
*
* Restore power to the device's PM domain, if necessary, and start the device.
*/
static int pm_genpd_resume_noirq(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
if (genpd->suspend_power_off
|| (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
return 0;
/*
* Since all of the "noirq" callbacks are executed sequentially, it is
* guaranteed that this function will never run twice in parallel for
* the same PM domain, so it is not necessary to use locking here.
*/
pm_genpd_sync_poweron(genpd);
genpd->suspended_count--;
return genpd_start_dev(genpd, dev);
}
/**
* pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
* @dev: Device to resume.
*
* Carry out an early resume of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a power domain consisting of I/O
* devices.
*/
static int pm_genpd_resume_early(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_resume_early(dev);
}
/**
* pm_genpd_resume - Resume of device in an I/O PM domain.
* @dev: Device to resume.
*
* Resume a device under the assumption that its pm_domain field points to the
* domain member of an object of type struct generic_pm_domain representing
* a power domain consisting of I/O devices.
*/
static int pm_genpd_resume(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
}
/**
* pm_genpd_freeze - Freezing a device in an I/O PM domain.
* @dev: Device to freeze.
*
* Freeze a device under the assumption that its pm_domain field points to the
* domain member of an object of type struct generic_pm_domain representing
* a power domain consisting of I/O devices.
*/
static int pm_genpd_freeze(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
}
/**
* pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
* @dev: Device to freeze.
*
* Carry out a late freeze of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a power domain consisting of I/O
* devices.
*/
static int pm_genpd_freeze_late(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_freeze_late(dev);
}
/**
* pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
* @dev: Device to freeze.
*
* Carry out a late freeze of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a power domain consisting of I/O
* devices.
*/
static int pm_genpd_freeze_noirq(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
}
/**
* pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
* @dev: Device to thaw.
*
* Start the device, unless power has been removed from the domain already
* before the system transition.
*/
static int pm_genpd_thaw_noirq(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
}
/**
* pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
* @dev: Device to thaw.
*
* Carry out an early thaw of a device under the assumption that its
* pm_domain field points to the domain member of an object of type
* struct generic_pm_domain representing a power domain consisting of I/O
* devices.
*/
static int pm_genpd_thaw_early(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_thaw_early(dev);
}
/**
* pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
* @dev: Device to thaw.
*
* Thaw a device under the assumption that its pm_domain field points to the
* domain member of an object of type struct generic_pm_domain representing
* a power domain consisting of I/O devices.
*/
static int pm_genpd_thaw(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
}
/**
* pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
* @dev: Device to resume.
*
* Make sure the domain will be in the same power state as before the
* hibernation the system is resuming from and start the device if necessary.
*/
static int pm_genpd_restore_noirq(struct device *dev)
{
struct generic_pm_domain *genpd;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return -EINVAL;
/*
* Since all of the "noirq" callbacks are executed sequentially, it is
* guaranteed that this function will never run twice in parallel for
* the same PM domain, so it is not necessary to use locking here.
*
* At this point suspended_count == 0 means we are being run for the
* first time for the given domain in the present cycle.
*/
if (genpd->suspended_count++ == 0) {
/*
* The boot kernel might put the domain into arbitrary state,
* so make it appear as powered off to pm_genpd_sync_poweron(),
* so that it tries to power it on in case it was really off.
*/
genpd->status = GPD_STATE_POWER_OFF;
if (genpd->suspend_power_off) {
/*
* If the domain was off before the hibernation, make
* sure it will be off going forward.
*/
genpd_power_off(genpd);
return 0;
}
}
if (genpd->suspend_power_off)
return 0;
pm_genpd_sync_poweron(genpd);
return genpd_start_dev(genpd, dev);
}
/**
* pm_genpd_complete - Complete power transition of a device in a power domain.
* @dev: Device to complete the transition of.
*
* Complete a power transition of a device (during a system-wide power
* transition) under the assumption that its pm_domain field points to the
* domain member of an object of type struct generic_pm_domain representing
* a power domain consisting of I/O devices.
*/
static void pm_genpd_complete(struct device *dev)
{
struct generic_pm_domain *genpd;
bool run_complete;
dev_dbg(dev, "%s()\n", __func__);
genpd = dev_to_genpd(dev);
if (IS_ERR(genpd))
return;
mutex_lock(&genpd->lock);
run_complete = !genpd->suspend_power_off;
if (--genpd->prepared_count == 0)
genpd->suspend_power_off = false;
mutex_unlock(&genpd->lock);
if (run_complete) {
pm_generic_complete(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
pm_request_idle(dev);
}
}
/**
* genpd_syscore_switch - Switch power during system core suspend or resume.
* @dev: Device that normally is marked as "always on" to switch power for.
*
* This routine may only be called during the system core (syscore) suspend or
* resume phase for devices whose "always on" flags are set.
*/
static void genpd_syscore_switch(struct device *dev, bool suspend)
{
struct generic_pm_domain *genpd;
genpd = dev_to_genpd(dev);
if (!pm_genpd_present(genpd))
return;
if (suspend) {
genpd->suspended_count++;
pm_genpd_sync_poweroff(genpd);
} else {
pm_genpd_sync_poweron(genpd);
genpd->suspended_count--;
}
}
void pm_genpd_syscore_poweroff(struct device *dev)
{
genpd_syscore_switch(dev, true);
}
EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);
void pm_genpd_syscore_poweron(struct device *dev)
{
genpd_syscore_switch(dev, false);
}
EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
#else /* !CONFIG_PM_SLEEP */
#define pm_genpd_prepare NULL
#define pm_genpd_suspend NULL
#define pm_genpd_suspend_late NULL
#define pm_genpd_suspend_noirq NULL
#define pm_genpd_resume_early NULL
#define pm_genpd_resume_noirq NULL
#define pm_genpd_resume NULL
#define pm_genpd_freeze NULL
#define pm_genpd_freeze_late NULL
#define pm_genpd_freeze_noirq NULL
#define pm_genpd_thaw_early NULL
#define pm_genpd_thaw_noirq NULL
#define pm_genpd_thaw NULL
#define pm_genpd_restore_noirq NULL
#define pm_genpd_complete NULL
#endif /* CONFIG_PM_SLEEP */
static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
struct generic_pm_domain *genpd,
struct gpd_timing_data *td)
{
struct generic_pm_domain_data *gpd_data;
int ret;
ret = dev_pm_get_subsys_data(dev);
if (ret)
return ERR_PTR(ret);
gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
if (!gpd_data) {
ret = -ENOMEM;
goto err_put;
}
if (td)
gpd_data->td = *td;
gpd_data->base.dev = dev;
gpd_data->need_restore = -1;
gpd_data->td.constraint_changed = true;
gpd_data->td.effective_constraint_ns = -1;
gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
spin_lock_irq(&dev->power.lock);
if (dev->power.subsys_data->domain_data) {
ret = -EINVAL;
goto err_free;
}
dev->power.subsys_data->domain_data = &gpd_data->base;
dev->pm_domain = &genpd->domain;
spin_unlock_irq(&dev->power.lock);
return gpd_data;
err_free:
spin_unlock_irq(&dev->power.lock);
kfree(gpd_data);
err_put:
dev_pm_put_subsys_data(dev);
return ERR_PTR(ret);
}
static void genpd_free_dev_data(struct device *dev,
struct generic_pm_domain_data *gpd_data)
{
spin_lock_irq(&dev->power.lock);
dev->pm_domain = NULL;
dev->power.subsys_data->domain_data = NULL;
spin_unlock_irq(&dev->power.lock);
kfree(gpd_data);
dev_pm_put_subsys_data(dev);
}
/**
* __pm_genpd_add_device - Add a device to an I/O PM domain.
* @genpd: PM domain to add the device to.
* @dev: Device to be added.
* @td: Set of PM QoS timing parameters to attach to the device.
*/
int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
struct gpd_timing_data *td)
{
struct generic_pm_domain_data *gpd_data;
int ret = 0;
dev_dbg(dev, "%s()\n", __func__);
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
return -EINVAL;
gpd_data = genpd_alloc_dev_data(dev, genpd, td);
if (IS_ERR(gpd_data))
return PTR_ERR(gpd_data);
genpd_acquire_lock(genpd);
if (genpd->prepared_count > 0) {
ret = -EAGAIN;
goto out;
}
ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
if (ret)
goto out;
genpd->device_count++;
genpd->max_off_time_changed = true;
list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
out:
genpd_release_lock(genpd);
if (ret)
genpd_free_dev_data(dev, gpd_data);
else
dev_pm_qos_add_notifier(dev, &gpd_data->nb);
return ret;
}
/**
* __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
* @domain_name: Name of the PM domain to add the device to.
* @dev: Device to be added.
* @td: Set of PM QoS timing parameters to attach to the device.
*/
int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
struct gpd_timing_data *td)
{
return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
}
/**
* pm_genpd_remove_device - Remove a device from an I/O PM domain.
* @genpd: PM domain to remove the device from.
* @dev: Device to be removed.
*/
int pm_genpd_remove_device(struct generic_pm_domain *genpd,
struct device *dev)
{
struct generic_pm_domain_data *gpd_data;
struct pm_domain_data *pdd;
int ret = 0;
dev_dbg(dev, "%s()\n", __func__);
if (!genpd || genpd != pm_genpd_lookup_dev(dev))
return -EINVAL;
/* The above validation also means we have existing domain_data. */
pdd = dev->power.subsys_data->domain_data;
gpd_data = to_gpd_data(pdd);
dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
genpd_acquire_lock(genpd);
if (genpd->prepared_count > 0) {
ret = -EAGAIN;
goto out;
}
genpd->device_count--;
genpd->max_off_time_changed = true;
if (genpd->detach_dev)
genpd->detach_dev(genpd, dev);
list_del_init(&pdd->list_node);
genpd_release_lock(genpd);
genpd_free_dev_data(dev, gpd_data);
return 0;
out:
genpd_release_lock(genpd);
dev_pm_qos_add_notifier(dev, &gpd_data->nb);
return ret;
}
/**
* pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
* @genpd: Master PM domain to add the subdomain to.
* @subdomain: Subdomain to be added.
*/
int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *subdomain)
{
struct gpd_link *link;
int ret = 0;
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
|| genpd == subdomain)
return -EINVAL;
start:
genpd_acquire_lock(genpd);
mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
if (subdomain->status != GPD_STATE_POWER_OFF
&& subdomain->status != GPD_STATE_ACTIVE) {
mutex_unlock(&subdomain->lock);
genpd_release_lock(genpd);
goto start;
}
if (genpd->status == GPD_STATE_POWER_OFF
&& subdomain->status != GPD_STATE_POWER_OFF) {
ret = -EINVAL;
goto out;
}
list_for_each_entry(link, &genpd->master_links, master_node) {
if (link->slave == subdomain && link->master == genpd) {
ret = -EINVAL;
goto out;
}
}
link = kzalloc(sizeof(*link), GFP_KERNEL);
if (!link) {
ret = -ENOMEM;
goto out;
}
link->master = genpd;
list_add_tail(&link->master_node, &genpd->master_links);
link->slave = subdomain;
list_add_tail(&link->slave_node, &subdomain->slave_links);
if (subdomain->status != GPD_STATE_POWER_OFF)
genpd_sd_counter_inc(genpd);
out:
mutex_unlock(&subdomain->lock);
genpd_release_lock(genpd);
return ret;
}
/**
* pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
* @master_name: Name of the master PM domain to add the subdomain to.
* @subdomain_name: Name of the subdomain to be added.
*/
int pm_genpd_add_subdomain_names(const char *master_name,
const char *subdomain_name)
{
struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;
if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
return -EINVAL;
mutex_lock(&gpd_list_lock);
list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
if (!master && !strcmp(gpd->name, master_name))
master = gpd;
if (!subdomain && !strcmp(gpd->name, subdomain_name))
subdomain = gpd;
if (master && subdomain)
break;
}
mutex_unlock(&gpd_list_lock);
return pm_genpd_add_subdomain(master, subdomain);
}
/**
* pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
* @genpd: Master PM domain to remove the subdomain from.
* @subdomain: Subdomain to be removed.
*/
int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *subdomain)
{
struct gpd_link *link;
int ret = -EINVAL;
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
return -EINVAL;
start:
genpd_acquire_lock(genpd);
list_for_each_entry(link, &genpd->master_links, master_node) {
if (link->slave != subdomain)
continue;
mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
if (subdomain->status != GPD_STATE_POWER_OFF
&& subdomain->status != GPD_STATE_ACTIVE) {
mutex_unlock(&subdomain->lock);
genpd_release_lock(genpd);
goto start;
}
list_del(&link->master_node);
list_del(&link->slave_node);
kfree(link);
if (subdomain->status != GPD_STATE_POWER_OFF)
genpd_sd_counter_dec(genpd);
mutex_unlock(&subdomain->lock);
ret = 0;
break;
}
genpd_release_lock(genpd);
return ret;
}
/**
* pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
* @genpd: PM domain to be connected with cpuidle.
* @state: cpuidle state this domain can disable/enable.
*
* Make a PM domain behave as though it contained a CPU core, that is, instead
* of calling its power down routine it will enable the given cpuidle state so
* that the cpuidle subsystem can power it down (if possible and desirable).
*/
int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
{
struct cpuidle_driver *cpuidle_drv;
struct gpd_cpuidle_data *cpuidle_data;
struct cpuidle_state *idle_state;
int ret = 0;
if (IS_ERR_OR_NULL(genpd) || state < 0)
return -EINVAL;
genpd_acquire_lock(genpd);
if (genpd->cpuidle_data) {
ret = -EEXIST;
goto out;
}
cpuidle_data = kzalloc(sizeof(*cpuidle_data), GFP_KERNEL);
if (!cpuidle_data) {
ret = -ENOMEM;
goto out;
}
cpuidle_drv = cpuidle_driver_ref();
if (!cpuidle_drv) {
ret = -ENODEV;
goto err_drv;
}
if (cpuidle_drv->state_count <= state) {
ret = -EINVAL;
goto err;
}
idle_state = &cpuidle_drv->states[state];
if (!idle_state->disabled) {
ret = -EAGAIN;
goto err;
}
cpuidle_data->idle_state = idle_state;
cpuidle_data->saved_exit_latency = idle_state->exit_latency;
genpd->cpuidle_data = cpuidle_data;
genpd_recalc_cpu_exit_latency(genpd);
out:
genpd_release_lock(genpd);
return ret;
err:
cpuidle_driver_unref();
err_drv:
kfree(cpuidle_data);
goto out;
}
/**
* pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
* @name: Name of the domain to connect to cpuidle.
* @state: cpuidle state this domain can manipulate.
*/
int pm_genpd_name_attach_cpuidle(const char *name, int state)
{
return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
}
/**
* pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
* @genpd: PM domain to remove the cpuidle connection from.
*
* Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
* given PM domain.
*/
int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
{
struct gpd_cpuidle_data *cpuidle_data;
struct cpuidle_state *idle_state;
int ret = 0;
if (IS_ERR_OR_NULL(genpd))
return -EINVAL;
genpd_acquire_lock(genpd);
cpuidle_data = genpd->cpuidle_data;
if (!cpuidle_data) {
ret = -ENODEV;
goto out;
}
idle_state = cpuidle_data->idle_state;
if (!idle_state->disabled) {
ret = -EAGAIN;
goto out;
}
idle_state->exit_latency = cpuidle_data->saved_exit_latency;
cpuidle_driver_unref();
genpd->cpuidle_data = NULL;
kfree(cpuidle_data);
out:
genpd_release_lock(genpd);
return ret;
}
/**
* pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
* @name: Name of the domain to disconnect cpuidle from.
*/
int pm_genpd_name_detach_cpuidle(const char *name)
{
return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
}
/* Default device callbacks for generic PM domains. */
/**
* pm_genpd_default_save_state - Default "save device state" for PM domains.
* @dev: Device to handle.
*/
static int pm_genpd_default_save_state(struct device *dev)
{
int (*cb)(struct device *__dev);
if (dev->type && dev->type->pm)
cb = dev->type->pm->runtime_suspend;
else if (dev->class && dev->class->pm)
cb = dev->class->pm->runtime_suspend;
else if (dev->bus && dev->bus->pm)
cb = dev->bus->pm->runtime_suspend;
else
cb = NULL;
if (!cb && dev->driver && dev->driver->pm)
cb = dev->driver->pm->runtime_suspend;
return cb ? cb(dev) : 0;
}
/**
* pm_genpd_default_restore_state - Default PM domains "restore device state".
* @dev: Device to handle.
*/
static int pm_genpd_default_restore_state(struct device *dev)
{
int (*cb)(struct device *__dev);
if (dev->type && dev->type->pm)
cb = dev->type->pm->runtime_resume;
else if (dev->class && dev->class->pm)
cb = dev->class->pm->runtime_resume;
else if (dev->bus && dev->bus->pm)
cb = dev->bus->pm->runtime_resume;
else
cb = NULL;
if (!cb && dev->driver && dev->driver->pm)
cb = dev->driver->pm->runtime_resume;
return cb ? cb(dev) : 0;
}
/**
* pm_genpd_init - Initialize a generic I/O PM domain object.
* @genpd: PM domain object to initialize.
* @gov: PM domain governor to associate with the domain (may be NULL).
* @is_off: Initial value of the domain's power_is_off field.
*/
void pm_genpd_init(struct generic_pm_domain *genpd,
struct dev_power_governor *gov, bool is_off)
{
if (IS_ERR_OR_NULL(genpd))
return;
INIT_LIST_HEAD(&genpd->master_links);
INIT_LIST_HEAD(&genpd->slave_links);
INIT_LIST_HEAD(&genpd->dev_list);
mutex_init(&genpd->lock);
genpd->gov = gov;
INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
genpd->in_progress = 0;
atomic_set(&genpd->sd_count, 0);
genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
init_waitqueue_head(&genpd->status_wait_queue);
genpd->poweroff_task = NULL;
genpd->resume_count = 0;
genpd->device_count = 0;
genpd->max_off_time_ns = -1;
genpd->max_off_time_changed = true;
genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
genpd->domain.ops.prepare = pm_genpd_prepare;
genpd->domain.ops.suspend = pm_genpd_suspend;
genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
genpd->domain.ops.resume_early = pm_genpd_resume_early;
genpd->domain.ops.resume = pm_genpd_resume;
genpd->domain.ops.freeze = pm_genpd_freeze;
genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
genpd->domain.ops.thaw = pm_genpd_thaw;
genpd->domain.ops.poweroff = pm_genpd_suspend;
genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
genpd->domain.ops.restore_early = pm_genpd_resume_early;
genpd->domain.ops.restore = pm_genpd_resume;
genpd->domain.ops.complete = pm_genpd_complete;
genpd->dev_ops.save_state = pm_genpd_default_save_state;
genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
if (genpd->flags & GENPD_FLAG_PM_CLK) {
genpd->dev_ops.stop = pm_clk_suspend;
genpd->dev_ops.start = pm_clk_resume;
}
mutex_lock(&gpd_list_lock);
list_add(&genpd->gpd_list_node, &gpd_list);
mutex_unlock(&gpd_list_lock);
}
#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
/*
* Device Tree based PM domain providers.
*
* The code below implements generic device tree based PM domain providers that
* bind device tree nodes with generic PM domains registered in the system.
*
* Any driver that registers generic PM domains and needs to support binding of
* devices to these domains is supposed to register a PM domain provider, which
* maps a PM domain specifier retrieved from the device tree to a PM domain.
*
* Two simple mapping functions have been provided for convenience:
* - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
* - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
* index.
*/
/**
* struct of_genpd_provider - PM domain provider registration structure
* @link: Entry in global list of PM domain providers
* @node: Pointer to device tree node of PM domain provider
* @xlate: Provider-specific xlate callback mapping a set of specifier cells
* into a PM domain.
* @data: context pointer to be passed into @xlate callback
*/
struct of_genpd_provider {
struct list_head link;
struct device_node *node;
genpd_xlate_t xlate;
void *data;
};
/* List of registered PM domain providers. */
static LIST_HEAD(of_genpd_providers);
/* Mutex to protect the list above. */
static DEFINE_MUTEX(of_genpd_mutex);
/**
* __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
* @genpdspec: OF phandle args to map into a PM domain
* @data: xlate function private data - pointer to struct generic_pm_domain
*
* This is a generic xlate function that can be used to model PM domains that
* have their own device tree nodes. The private data of xlate function needs
* to be a valid pointer to struct generic_pm_domain.
*/
struct generic_pm_domain *__of_genpd_xlate_simple(
struct of_phandle_args *genpdspec,
void *data)
{
if (genpdspec->args_count != 0)
return ERR_PTR(-EINVAL);
return data;
}
EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);
/**
* __of_genpd_xlate_onecell() - Xlate function using a single index.
* @genpdspec: OF phandle args to map into a PM domain
* @data: xlate function private data - pointer to struct genpd_onecell_data
*
* This is a generic xlate function that can be used to model simple PM domain
* controllers that have one device tree node and provide multiple PM domains.
* A single cell is used as an index into an array of PM domains specified in
* the genpd_onecell_data struct when registering the provider.
*/
struct generic_pm_domain *__of_genpd_xlate_onecell(
struct of_phandle_args *genpdspec,
void *data)
{
struct genpd_onecell_data *genpd_data = data;
unsigned int idx = genpdspec->args[0];
if (genpdspec->args_count != 1)
return ERR_PTR(-EINVAL);
if (idx >= genpd_data->num_domains) {
pr_err("%s: invalid domain index %u\n", __func__, idx);
return ERR_PTR(-EINVAL);
}
if (!genpd_data->domains[idx])
return ERR_PTR(-ENOENT);
return genpd_data->domains[idx];
}
EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);
/**
* __of_genpd_add_provider() - Register a PM domain provider for a node
* @np: Device node pointer associated with the PM domain provider.
* @xlate: Callback for decoding PM domain from phandle arguments.
* @data: Context pointer for @xlate callback.
*/
int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
void *data)
{
struct of_genpd_provider *cp;
cp = kzalloc(sizeof(*cp), GFP_KERNEL);
if (!cp)
return -ENOMEM;
cp->node = of_node_get(np);
cp->data = data;
cp->xlate = xlate;
mutex_lock(&of_genpd_mutex);
list_add(&cp->link, &of_genpd_providers);
mutex_unlock(&of_genpd_mutex);
pr_debug("Added domain provider from %s\n", np->full_name);
return 0;
}
EXPORT_SYMBOL_GPL(__of_genpd_add_provider);
/**
* of_genpd_del_provider() - Remove a previously registered PM domain provider
* @np: Device node pointer associated with the PM domain provider
*/
void of_genpd_del_provider(struct device_node *np)
{
struct of_genpd_provider *cp;
mutex_lock(&of_genpd_mutex);
list_for_each_entry(cp, &of_genpd_providers, link) {
if (cp->node == np) {
list_del(&cp->link);
of_node_put(cp->node);
kfree(cp);
break;
}
}
mutex_unlock(&of_genpd_mutex);
}
EXPORT_SYMBOL_GPL(of_genpd_del_provider);
/**
* of_genpd_get_from_provider() - Look-up PM domain
* @genpdspec: OF phandle args to use for look-up
*
* Looks for a PM domain provider under the node specified by @genpdspec and if
* found, uses xlate function of the provider to map phandle args to a PM
* domain.
*
* Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
* on failure.
*/
struct generic_pm_domain *of_genpd_get_from_provider(
struct of_phandle_args *genpdspec)
{
struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
struct of_genpd_provider *provider;
mutex_lock(&of_genpd_mutex);
/* Check if we have such a provider in our array */
list_for_each_entry(provider, &of_genpd_providers, link) {
if (provider->node == genpdspec->np)
genpd = provider->xlate(genpdspec, provider->data);
if (!IS_ERR(genpd))
break;
}
mutex_unlock(&of_genpd_mutex);
return genpd;
}
EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
/**
* genpd_dev_pm_detach - Detach a device from its PM domain.
* @dev: Device to attach.
* @power_off: Currently not used
*
* Try to locate a corresponding generic PM domain, which the device was
* attached to previously. If such is found, the device is detached from it.
*/
static void genpd_dev_pm_detach(struct device *dev, bool power_off)
{
struct generic_pm_domain *pd;
int ret = 0;
pd = pm_genpd_lookup_dev(dev);
if (!pd)
return;
dev_dbg(dev, "removing from PM domain %s\n", pd->name);
while (1) {
ret = pm_genpd_remove_device(pd, dev);
if (ret != -EAGAIN)
break;
cond_resched();
}
if (ret < 0) {
dev_err(dev, "failed to remove from PM domain %s: %d",
pd->name, ret);
return;
}
/* Check if PM domain can be powered off after removing this device. */
genpd_queue_power_off_work(pd);
}
static void genpd_dev_pm_sync(struct device *dev)
{
struct generic_pm_domain *pd;
pd = dev_to_genpd(dev);
if (IS_ERR(pd))
return;
genpd_queue_power_off_work(pd);
}
/**
* genpd_dev_pm_attach - Attach a device to its PM domain using DT.
* @dev: Device to attach.
*
* Parse device's OF node to find a PM domain specifier. If such is found,
* attaches the device to retrieved pm_domain ops.
*
* Both generic and legacy Samsung-specific DT bindings are supported to keep
* backwards compatibility with existing DTBs.
*
* Returns 0 on successfully attached PM domain or negative error code.
*/
int genpd_dev_pm_attach(struct device *dev)
{
struct of_phandle_args pd_args;
struct generic_pm_domain *pd;
int ret;
if (!dev->of_node)
return -ENODEV;
if (dev->pm_domain)
return -EEXIST;
ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
"#power-domain-cells", 0, &pd_args);
if (ret < 0) {
if (ret != -ENOENT)
return ret;
/*
* Try legacy Samsung-specific bindings
* (for backwards compatibility of DT ABI)
*/
pd_args.args_count = 0;
pd_args.np = of_parse_phandle(dev->of_node,
"samsung,power-domain", 0);
if (!pd_args.np)
return -ENOENT;
}
pd = of_genpd_get_from_provider(&pd_args);
if (IS_ERR(pd)) {
dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
__func__, PTR_ERR(pd));
of_node_put(dev->of_node);
return PTR_ERR(pd);
}
dev_dbg(dev, "adding to PM domain %s\n", pd->name);
while (1) {
ret = pm_genpd_add_device(pd, dev);
if (ret != -EAGAIN)
break;
cond_resched();
}
if (ret < 0) {
dev_err(dev, "failed to add to PM domain %s: %d",
pd->name, ret);
of_node_put(dev->of_node);
return ret;
}
dev->pm_domain->detach = genpd_dev_pm_detach;
dev->pm_domain->sync = genpd_dev_pm_sync;
pm_genpd_poweron(pd);
return 0;
}
EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
/*** debugfs support ***/
#ifdef CONFIG_PM_ADVANCED_DEBUG
#include <linux/pm.h>
#include <linux/device.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/kobject.h>
static struct dentry *pm_genpd_debugfs_dir;
/*
* TODO: This function is a slightly modified version of rtpm_status_show
* from sysfs.c, so generalize it.
*/
static void rtpm_status_str(struct seq_file *s, struct device *dev)
{
static const char * const status_lookup[] = {
[RPM_ACTIVE] = "active",
[RPM_RESUMING] = "resuming",
[RPM_SUSPENDED] = "suspended",
[RPM_SUSPENDING] = "suspending"
};
const char *p = "";
if (dev->power.runtime_error)
p = "error";
else if (dev->power.disable_depth)
p = "unsupported";
else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
p = status_lookup[dev->power.runtime_status];
else
WARN_ON(1);
seq_puts(s, p);
}
static int pm_genpd_summary_one(struct seq_file *s,
struct generic_pm_domain *genpd)
{
static const char * const status_lookup[] = {
[GPD_STATE_ACTIVE] = "on",
[GPD_STATE_WAIT_MASTER] = "wait-master",
[GPD_STATE_BUSY] = "busy",
[GPD_STATE_REPEAT] = "off-in-progress",
[GPD_STATE_POWER_OFF] = "off"
};
struct pm_domain_data *pm_data;
const char *kobj_path;
struct gpd_link *link;
int ret;
ret = mutex_lock_interruptible(&genpd->lock);
if (ret)
return -ERESTARTSYS;
if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
goto exit;
seq_printf(s, "%-30s %-15s ", genpd->name, status_lookup[genpd->status]);
/*
* Modifications on the list require holding locks on both
* master and slave, so we are safe.
* Also genpd->name is immutable.
*/
list_for_each_entry(link, &genpd->master_links, master_node) {
seq_printf(s, "%s", link->slave->name);
if (!list_is_last(&link->master_node, &genpd->master_links))
seq_puts(s, ", ");
}
list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL);
if (kobj_path == NULL)
continue;
seq_printf(s, "\n %-50s ", kobj_path);
rtpm_status_str(s, pm_data->dev);
kfree(kobj_path);
}
seq_puts(s, "\n");
exit:
mutex_unlock(&genpd->lock);
return 0;
}
static int pm_genpd_summary_show(struct seq_file *s, void *data)
{
struct generic_pm_domain *genpd;
int ret = 0;
seq_puts(s, " domain status slaves\n");
seq_puts(s, " /device runtime status\n");
seq_puts(s, "----------------------------------------------------------------------\n");
ret = mutex_lock_interruptible(&gpd_list_lock);
if (ret)
return -ERESTARTSYS;
list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
ret = pm_genpd_summary_one(s, genpd);
if (ret)
break;
}
mutex_unlock(&gpd_list_lock);
return ret;
}
static int pm_genpd_summary_open(struct inode *inode, struct file *file)
{
return single_open(file, pm_genpd_summary_show, NULL);
}
static const struct file_operations pm_genpd_summary_fops = {
.open = pm_genpd_summary_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init pm_genpd_debug_init(void)
{
struct dentry *d;
pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
if (!pm_genpd_debugfs_dir)
return -ENOMEM;
d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
if (!d)
return -ENOMEM;
return 0;
}
late_initcall(pm_genpd_debug_init);
static void __exit pm_genpd_debug_exit(void)
{
debugfs_remove_recursive(pm_genpd_debugfs_dir);
}
__exitcall(pm_genpd_debug_exit);
#endif /* CONFIG_PM_ADVANCED_DEBUG */