These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / Documentation / power / devices.txt

diff --git a/kernel/Documentation/power/devices.txt b/kernel/Documentation/power/devices.txt
index d172bce..8ba6625 100644 (file)
--- a/kernel/Documentation/power/devices.txt
+++ b/kernel/Documentation/power/devices.txt
@@ -341,6 +341,13 @@ the phases are:
        and is entirely responsible for bringing the device back to the
        functional state as appropriate.
 
+       Note that this direct-complete procedure applies even if the device is
+       disabled for runtime PM; only the runtime-PM status matters.  It follows
+       that if a device has system-sleep callbacks but does not support runtime
+       PM, then its prepare callback must never return a positive value.  This
+       is because all devices are initially set to runtime-suspended with
+       runtime PM disabled.
+
     2. The suspend methods should quiesce the device to stop it from performing
        I/O.  They also may save the device registers and put it into the
        appropriate low-power state, depending on the bus type the device is on,