mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 06:37:05 +07:00
e79aee49bc
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: 989561de9b (PM / Domains: add setter for dev.pm_domain)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Sinan Kaya <okaya@codeaurora.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
155 lines
4.1 KiB
C
155 lines
4.1 KiB
C
/*
|
|
* drivers/base/power/common.c - Common device power management code.
|
|
*
|
|
* 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/device.h>
|
|
#include <linux/export.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/pm_clock.h>
|
|
#include <linux/acpi.h>
|
|
#include <linux/pm_domain.h>
|
|
|
|
#include "power.h"
|
|
|
|
/**
|
|
* dev_pm_get_subsys_data - Create or refcount power.subsys_data for device.
|
|
* @dev: Device to handle.
|
|
*
|
|
* If power.subsys_data is NULL, point it to a new object, otherwise increment
|
|
* its reference counter. Return 0 if new object has been created or refcount
|
|
* increased, otherwise negative error code.
|
|
*/
|
|
int dev_pm_get_subsys_data(struct device *dev)
|
|
{
|
|
struct pm_subsys_data *psd;
|
|
|
|
psd = kzalloc(sizeof(*psd), GFP_KERNEL);
|
|
if (!psd)
|
|
return -ENOMEM;
|
|
|
|
spin_lock_irq(&dev->power.lock);
|
|
|
|
if (dev->power.subsys_data) {
|
|
dev->power.subsys_data->refcount++;
|
|
} else {
|
|
spin_lock_init(&psd->lock);
|
|
psd->refcount = 1;
|
|
dev->power.subsys_data = psd;
|
|
pm_clk_init(dev);
|
|
psd = NULL;
|
|
}
|
|
|
|
spin_unlock_irq(&dev->power.lock);
|
|
|
|
/* kfree() verifies that its argument is nonzero. */
|
|
kfree(psd);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dev_pm_get_subsys_data);
|
|
|
|
/**
|
|
* dev_pm_put_subsys_data - Drop reference to power.subsys_data.
|
|
* @dev: Device to handle.
|
|
*
|
|
* If the reference counter of power.subsys_data is zero after dropping the
|
|
* reference, power.subsys_data is removed.
|
|
*/
|
|
void dev_pm_put_subsys_data(struct device *dev)
|
|
{
|
|
struct pm_subsys_data *psd;
|
|
|
|
spin_lock_irq(&dev->power.lock);
|
|
|
|
psd = dev_to_psd(dev);
|
|
if (!psd)
|
|
goto out;
|
|
|
|
if (--psd->refcount == 0)
|
|
dev->power.subsys_data = NULL;
|
|
else
|
|
psd = NULL;
|
|
|
|
out:
|
|
spin_unlock_irq(&dev->power.lock);
|
|
kfree(psd);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dev_pm_put_subsys_data);
|
|
|
|
/**
|
|
* dev_pm_domain_attach - Attach a device to its PM domain.
|
|
* @dev: Device to attach.
|
|
* @power_on: Used to indicate whether we should power on the device.
|
|
*
|
|
* The @dev may only be attached to a single PM domain. By iterating through
|
|
* the available alternatives we try to find a valid PM domain for the device.
|
|
* As attachment succeeds, the ->detach() callback in the struct dev_pm_domain
|
|
* should be assigned by the corresponding attach function.
|
|
*
|
|
* This function should typically be invoked from subsystem level code during
|
|
* the probe phase. Especially for those that holds devices which requires
|
|
* power management through PM domains.
|
|
*
|
|
* Callers must ensure proper synchronization of this function with power
|
|
* management callbacks.
|
|
*
|
|
* Returns 0 on successfully attached PM domain or negative error code.
|
|
*/
|
|
int dev_pm_domain_attach(struct device *dev, bool power_on)
|
|
{
|
|
int ret;
|
|
|
|
ret = acpi_dev_pm_attach(dev, power_on);
|
|
if (ret)
|
|
ret = genpd_dev_pm_attach(dev);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dev_pm_domain_attach);
|
|
|
|
/**
|
|
* dev_pm_domain_detach - Detach a device from its PM domain.
|
|
* @dev: Device to detach.
|
|
* @power_off: Used to indicate whether we should power off the device.
|
|
*
|
|
* This functions will reverse the actions from dev_pm_domain_attach() and thus
|
|
* try to detach the @dev from its PM domain. Typically it should be invoked
|
|
* from subsystem level code during the remove phase.
|
|
*
|
|
* Callers must ensure proper synchronization of this function with power
|
|
* management callbacks.
|
|
*/
|
|
void dev_pm_domain_detach(struct device *dev, bool power_off)
|
|
{
|
|
if (dev->pm_domain && dev->pm_domain->detach)
|
|
dev->pm_domain->detach(dev, power_off);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dev_pm_domain_detach);
|
|
|
|
/**
|
|
* dev_pm_domain_set - Set PM domain of a device.
|
|
* @dev: Device whose PM domain is to be set.
|
|
* @pd: PM domain to be set, or NULL.
|
|
*
|
|
* Sets the PM domain the device belongs to. The PM domain of a device needs
|
|
* to be set before its probe finishes (it's bound to a driver).
|
|
*
|
|
* This function must be called with the device lock held.
|
|
*/
|
|
void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd)
|
|
{
|
|
if (dev->pm_domain == pd)
|
|
return;
|
|
|
|
WARN(pd && device_is_bound(dev),
|
|
"PM domains can only be changed for unbound devices\n");
|
|
dev->pm_domain = pd;
|
|
device_pm_check_callbacks(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dev_pm_domain_set);
|