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Based on kernel version 3.13. Page generated on 2014-01-20 22:04 EST.

1	Testing suspend and resume support in device drivers
2		(C) 2007 Rafael J. Wysocki <rjw@sisk.pl>, GPL
3	
4	1. Preparing the test system
5	
6	Unfortunately, to effectively test the support for the system-wide suspend and
7	resume transitions in a driver, it is necessary to suspend and resume a fully
8	functional system with this driver loaded.  Moreover, that should be done
9	several times, preferably several times in a row, and separately for hibernation
10	(aka suspend to disk or STD) and suspend to RAM (STR), because each of these
11	cases involves slightly different operations and different interactions with
12	the machine's BIOS.
13	
14	Of course, for this purpose the test system has to be known to suspend and
15	resume without the driver being tested.  Thus, if possible, you should first
16	resolve all suspend/resume-related problems in the test system before you start
17	testing the new driver.  Please see Documentation/power/basic-pm-debugging.txt
18	for more information about the debugging of suspend/resume functionality.
19	
20	2. Testing the driver
21	
22	Once you have resolved the suspend/resume-related problems with your test system
23	without the new driver, you are ready to test it:
24	
25	a) Build the driver as a module, load it and try the test modes of hibernation
26	   (see: Documentation/power/basic-pm-debugging.txt, 1).
27	
28	b) Load the driver and attempt to hibernate in the "reboot", "shutdown" and
29	   "platform" modes (see: Documentation/power/basic-pm-debugging.txt, 1).
30	
31	c) Compile the driver directly into the kernel and try the test modes of
32	   hibernation.
33	
34	d) Attempt to hibernate with the driver compiled directly into the kernel
35	   in the "reboot", "shutdown" and "platform" modes.
36	
37	e) Try the test modes of suspend (see: Documentation/power/basic-pm-debugging.txt,
38	   2).  [As far as the STR tests are concerned, it should not matter whether or
39	   not the driver is built as a module.]
40	
41	f) Attempt to suspend to RAM using the s2ram tool with the driver loaded
42	   (see: Documentation/power/basic-pm-debugging.txt, 2).
43	
44	Each of the above tests should be repeated several times and the STD tests
45	should be mixed with the STR tests.  If any of them fails, the driver cannot be
46	regarded as suspend/resume-safe.
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