From: David Burg <daviburg@windows.microsoft.com>
To: "mtfuji5@avc-pioneer.com" <mtfuji5@avc-pioneer.com>,
        "t10@t10.org"
	<t10@t10.org>
Date: Thu, 2 Oct 2008 16:23:03 -0700
Subject: Mt Fuji / MMC: Power state reporting of CD / DVD / BD drives
X-Message-Number: 9161
Formatted message: HTML-formatted message
Attachment #1: image001.png
Attachment #2: image002.png

Hello,
I am currently working on power management of CD / DVD / BD devices and
observe a behavior that does not seem spec-compliant. I'd like to confirm
with the Fuji / MMC committee that such behavior is out of spec.
SPC-3r23 says:
"If the logical unit is in a power condition other than the active power
condition when a REQUEST SENSE command
is received and there is no ACA condition, it shall return the sense key set
to NO SENSE and the additional sense
code set to one of the following:
a) LOW POWER CONDITION ON if the reason for entry into the power condition is
unknown;
b) IDLE CONDITION ACTIVATED BY TIMER if the logical unit entered the idle
power condition due to the idle
condition timer (see 7.4.12);
c) STANDBY CONDITION ACTIVATED BY TIMER if the logical unit entered the
standby power condition due
to the standby condition timer (see 7.4.12);
d) IDLE CONDITION ACTIVATED BY COMMAND if the logical unit entered the idle
power condition due to
receipt of a command requiring the idle power condition while it was in the
standby power condition; or
e) Another additional sense code based on requirements specified in a command
standard (see 3.1.18).
On completion of the command the logical unit shall return to the same power
condition that was active before the
REQUEST SENSE command was received. A REQUEST SENSE command shall not reset
any power condition
timers."
I am issuing the following to get the device to Idle State:
[cid:image001.png@01C924AB.24E38D70]
Then query the state with Request Sense, but I don't see the power condition
in the additional sense code:
[cid:image002.png@01C924AB.24E38D70]
Shouldn't a spec-compliant device return its current power state in the
request sense answer? Do CD / DVD / BD drives use a different command to
indicate their current power state?
With regards,
David.