.TH "pm_send_all" 9 "pm_send_all" "25 May 1998" "Kernel Hacker's Manual" LINUX
.SH NAME
pm_send_all \-  send request to all managed devices
.SH SYNOPSIS
.B "int" pm_send_all
.BI "(pm_request_t " rqst ","
.BI "void *" data ");"
.SH ARGUMENTS
.IP "rqst" 12
 power management request
.IP "data" 12
 data for the callback
.SH "DESCRIPTION"
Issue a power management request to a all devices. The 
PM_SUSPEND events are handled specially. Any device is 
permitted to fail a suspend by returning a non zero (error)
value from its callback function. If any device vetoes a 
suspend request then all other devices that have suspended 
during the processing of this request are restored to their
previous state.
.SH "WARNING"
  This function takes the pm_devs_lock. The lock is not dropped until
the callbacks have completed. This prevents races against pm locking
functions, races against module unload pm_unregister code. It does
mean however that you must not issue pm_ functions within the callback
or you will deadlock and users will hate you.

Zero is returned on success. If a suspend fails then the status
from the device that vetoes the suspend is returned.
.SH "BUGS"
 what stops two power management requests occuring in parallel
and conflicting.