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Subject[PATCH] PM / Runtime: return the right value when deferred_resume is true in rpm_suspend()
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For the case that in rpm_suspend() and deferred_resume is true,
the rpm_resume() will be called, and if rpm_resume() return error,
at this time, the device is still in SUSPENDED state.

In this case it is still an suspend succeeding case, we should
return non-error instead of EAGAIN.

An example like below for this case:
CPU1: CPU2:
pm_runtime_get_sync()
pm_runtime_put_sync_suspend()
rpm_suspend()
__update_runtime_status(dev, RPM_SUSPENDING)
rpm_callback()
spin_unlock_irq()
... pm_runtime_get()
spin_lock_irqsave()
cb() rpm_resume()
... dev->power.deferred_resume = true
spin_unlock_irqrestore()
spin_lock_irq()
__update_runtime_status(dev, RPM_SUSPENDED)
rpm_resume() is called due to deferred_resume is true

Here if rpm_resume() failed in CPU1, the runtime_status is still SUSPENDED,
we should return 0 in this case.

Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
---
drivers/base/power/runtime.c | 8 +++++---
1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 3148b10..0adc713 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -436,9 +436,11 @@ static int rpm_suspend(struct device *dev, int rpmflags)

if (dev->power.deferred_resume) {
dev->power.deferred_resume = false;
- rpm_resume(dev, 0);
- retval = -EAGAIN;
- goto out;
+ if (rpm_resume(dev, 0) >= 0) {
+ /* In case resuming succeeded, return EAGAIN error */
+ retval = -EAGAIN;
+ goto out;
+ }
}

/* Maybe the parent is now able to suspend. */
--
1.7.0.4




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