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PM: domains: Don't check PM_QOS_FLAG_NO_POWER_OFF in genpd

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Back in the days when genpd supported intermediate power states of its
devices, it made sense to check the PM_QOS_FLAG_NO_POWER_OFF in
genpd_power_off(). This because the attached devices were all being put
into low power state together when the PM domain was also being powered
off.

At this point, the flag PM_QOS_FLAG_NO_POWER_OFF is better checked by
drivers from their ->runtime_suspend() callbacks, like in the
usb_port_runtime_suspend(), for example. Or perhaps an even better option
is to set the QoS resume latency constraint for the device to zero, which
informs the runtime PM core to prevent the device from being runtime
suspended.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Ulf Hansson 2022-05-11 16:56:53 +02:00 committed by Rafael J. Wysocki
parent fabb1c20b9
commit 3f9ee7da72
1 changed files with 0 additions and 6 deletions
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6
drivers/base/power/domain.c
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@ -648,12 +648,6 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
}
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);
if (stat > PM_QOS_FLAGS_NONE)
return -EBUSY;
/*
* Do not allow PM domain to be powered off, when an IRQ safe
* device is part of a non-IRQ safe domain.