// SPDX-License-Identifier: GPL-2.0
/* Device wakeirq helper functions */
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/pm_wakeirq.h>
#include "power.h"
/**
* dev_pm_attach_wake_irq - Attach device interrupt as a wake IRQ
* @dev: Device entry
* @wirq: Wake irq specific data
*
* Internal function to attach a dedicated wake-up interrupt as a wake IRQ.
*/
static int dev_pm_attach_wake_irq(struct device *dev, struct wake_irq *wirq)
{
unsigned long flags;
if (!dev || !wirq)
return -EINVAL;
spin_lock_irqsave(&dev->power.lock, flags);
if (dev_WARN_ONCE(dev, dev->power.wakeirq,
"wake irq already initialized\n")) {
spin_unlock_irqrestore(&dev->power.lock, flags);
return -EEXIST;
}
dev->power.wakeirq = wirq;
device_wakeup_attach_irq(dev, wirq);
spin_unlock_irqrestore(&dev->power.lock, flags);
return 0;
}
/**
* dev_pm_set_wake_irq - Attach device IO interrupt as wake IRQ
* @dev: Device entry
* @irq: Device IO interrupt
*
* Attach a device IO interrupt as a wake IRQ. The wake IRQ gets
* automatically configured for wake-up from suspend based
* on the device specific sysfs wakeup entry. Typically called
* during driver probe after calling device_init_wakeup().
*/
int dev_pm_set_wake_irq(struct device *dev, int irq)
{
struct wake_irq *wirq;
int err;
if (irq < 0)
return -EINVAL;
wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
if (!wirq)
return -ENOMEM;
wirq->dev = dev;
wirq->irq = irq;
err = dev_pm_attach_wake_irq(dev, wirq);
if (err)
kfree(wirq);
return err;
}
EXPORT_SYMBOL_GPL(dev_pm_set_wake_irq);
/**
* dev_pm_clear_wake_irq - Detach a device IO interrupt wake IRQ
* @dev: Device entry
*
* Detach a device wake IRQ and free resources.
*
* Note that it's OK for drivers to call this without calling
* dev_pm_set_wake_irq() as all the driver instances may not have
* a wake IRQ configured. This avoid adding wake IRQ specific
* checks into the drivers.
*/
void dev_pm_clear_wake_irq(struct device *dev)
{
struct wake_irq *wirq = dev->power.wakeirq;
unsigned long flags;
if (!wirq)
return;
spin_lock_irqsave(&dev->power.lock, flags);
device_wakeup_detach_irq(dev);
dev->power.wakeirq = NULL;
spin_unlock_irqrestore(&dev->power.lock, flags);
if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) {
free_irq(wirq->irq, wirq);
wirq->status &= ~WAKE_IRQ_DEDICATED_MASK;
}
kfree(wirq->name);
kfree(wirq);
}
EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
/**
* handle_threaded_wake_irq - Handler for dedicated wake-up interrupts
* @irq: Device specific dedicated wake-up interrupt
* @_wirq: Wake IRQ data
*
* Some devices have a separate wake-up interrupt in addition to the
* device IO interrupt. The wake-up interrupt signals that a device
* should be woken up from it's idle state. This handler uses device
* specific pm_runtime functions to wake the device, and then it's
* up to the device to do whatever it needs to. Note that as the
* device may need to restore context and start up regulators, we
* use a threaded IRQ.
*
* Also note that we are not resending the lost device interrupts.
* We assume that the wake-up interrupt just needs to wake-up the
* device, and then device's pm_runtime_resume() can deal with the
* situation.
*/
static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq)
{
struct wake_irq *wirq = _wirq;
int res;
/* Maybe abort suspend? */
if (irqd_is_wakeup_set(irq_get_irq_data(irq))) {
pm_wakeup_event(wirq->dev, 0);
return IRQ_HANDLED;
}
/* We don't want RPM_ASYNC or RPM_NOWAIT here */
res = pm_runtime_resume(wirq->dev);
if (res < 0)
dev_warn(wirq->dev,
"wake IRQ with no resume: %i\n", res);
return IRQ_HANDLED;
}
static int __dev_pm_set_dedicated_wake_irq(struct device *dev, int irq, unsigned int flag)
{
struct wake_irq *wirq;
int err;
if (irq < 0)
return -EINVAL;
wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
if (!wirq)
return -ENOMEM;
wirq->name = kasprintf(GFP_KERNEL, "%s:wakeup", dev_name(dev));
if (!wirq->name) {
err = -ENOMEM;
goto err_free;
}
wirq->dev = dev;
wirq->irq = irq;
/* Prevent deferred spurious wakeirqs with disable_irq_nosync() */
irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY);
/*
* Consumer device may need to power up and restore state
* so we use a threaded irq.
*/
err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
IRQF_ONESHOT | IRQF_NO_AUTOEN,
wirq->name, wirq);
if (err)
goto err_free_name;
err = dev_pm_attach_wake_irq(dev, wirq);
if (err)
goto err_free_irq;
wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED | flag;
return err;
err_free_irq:
free_irq(irq, wirq);
err_free_name:
kfree(wirq->name);
err_free:
kfree(wirq);
return err;
}
/**
* dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt
* @dev: Device entry
* @irq: Device wake-up interrupt
*
* Unless your hardware has separate wake-up interrupts in addition
* to the device IO interrupts, you don't need this.
*
* Sets up a threaded interrupt handler for a device that has
* a dedicated wake-up interrupt in addition to the device IO
* interrupt.
*/
int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
{
return __dev_pm_set_dedicated_wake_irq(dev, irq, 0);
}
EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq);
/**
* dev_pm_set_dedicated_wake_irq_reverse - Request a dedicated wake-up interrupt
* with reverse enable ordering
* @dev: Device entry
* @irq: Device wake-up interrupt
*
* Unless your hardware has separate wake-up interrupts in addition
* to the device IO interrupts, you don't need this.
*
* Sets up a threaded interrupt handler for a device that has a dedicated
* wake-up interrupt in addition to the device IO interrupt. It sets
* the status of WAKE_IRQ_DEDICATED_REVERSE to tell rpm_suspend()
* to enable dedicated wake-up interrupt after running the runtime suspend
* callback for @dev.
*/
int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq)
{
return __dev_pm_set_dedicated_wake_irq(dev, irq, WAKE_IRQ_DEDICATED_REVERSE);
}
EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq_reverse);
/**
* dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt
* @dev: Device
* @can_change_status: Can change wake-up interrupt status
*
* Enables wakeirq conditionally. We need to enable wake-up interrupt
* lazily on the first rpm_suspend(). This is needed as the consumer device
* starts in RPM_SUSPENDED state, and the first pm_runtime_get() would
* otherwise try to disable already disabled wakeirq. The wake-up interrupt
* starts disabled with IRQ_NOAUTOEN set.
*
* Should be only called from rpm_suspend() and rpm_resume() path.
* Caller must hold &dev->power.lock to change wirq->status
*/
void dev_pm_enable_wake_irq_check(struct device *dev,
bool can_change_status)
{
struct wake_irq *wirq = dev->power.wakeirq;
if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
return;
if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) {
goto enable;
} else if (can_change_status) {
wirq->status |= WAKE_IRQ_DEDICATED_MANAGED;
goto enable;
}
return;
enable:
if (!can_change_status || !(wirq->status & WAKE_IRQ_DEDICATED_REVERSE)) {
enable_irq(wirq->irq);
wirq->status |= WAKE_IRQ_DEDICATED_ENABLED;
}
}
/**
* dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt
* @dev: Device
* @cond_disable: if set, also check WAKE_IRQ_DEDICATED_REVERSE
*
* Disables wake-up interrupt conditionally based on status.
* Should be only called from rpm_suspend() and rpm_resume() path.
*/
void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable)
{
struct wake_irq *wirq = dev->power.wakeirq;
if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
return;
if (cond_disable && (wirq->status & WAKE_IRQ_DEDICATED_REVERSE))
return;
if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED) {
wirq->status &= ~WAKE_IRQ_DEDICATED_ENABLED;
disable_irq_nosync(wirq->irq);
}
}
/**
* dev_pm_enable_wake_irq_complete - enable wake IRQ not enabled before
* @dev: Device using the wake IRQ
*
* Enable wake IRQ conditionally based on status, mainly used if want to
* enable wake IRQ after running ->runtime_suspend() which depends on
* WAKE_IRQ_DEDICATED_REVERSE.
*
* Should be only called from rpm_suspend() path.
*/
void dev_pm_enable_wake_irq_complete(struct device *dev)
{
struct wake_irq *wirq = dev->power.wakeirq;
if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
return;
if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED &&
wirq->status & WAKE_IRQ_DEDICATED_REVERSE) {
enable_irq(wirq->irq);
wirq->status |= WAKE_IRQ_DEDICATED_ENABLED;
}
}
/**
* dev_pm_arm_wake_irq - Arm device wake-up
* @wirq: Device wake-up interrupt
*
* Sets up the wake-up event conditionally based on the
* device_may_wake().
*/
void dev_pm_arm_wake_irq(struct wake_irq *wirq)
{
if (!wirq)
return;
if (device_may_wakeup(wirq->dev)) {
if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
!(wirq->status & WAKE_IRQ_DEDICATED_ENABLED))
enable_irq(wirq->irq);
enable_irq_wake(wirq->irq);
}
}
/**
* dev_pm_disarm_wake_irq - Disarm device wake-up
* @wirq: Device wake-up interrupt
*
* Clears up the wake-up event conditionally based on the
* device_may_wake().
*/
void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
{
if (!wirq)
return;
if (device_may_wakeup(wirq->dev)) {
disable_irq_wake(wirq->irq);
if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
!(wirq->status & WAKE_IRQ_DEDICATED_ENABLED))
disable_irq_nosync(wirq->irq);
}
}
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