Re: Enable CONFIG_USB_SUSPEND by default or some mobile HD can'tbe unplugged safely

From: Alexander E. Patrakov
Date: Thu Jan 01 2009 - 12:33:54 EST




Yan Li wrote:
Hello List,

By default CONFIG_USB_SUSPEND is not enabled and today I got bite by
this when I got a new WDC My Book hard drive. I have no way to unplug
it safely, according to it's manual, with a kernel that doesn't have
CONFIG_USB_SUSPEND=y.

On it's manual read "you should unplug and remove the device only when
the light is off." On Linux unmounting it won't turn it's light off
and I can feel it's motor is still running. The only way to unplug it
properly on a Linux system, as to my knowledge, is to echo `suspend'
to `/sys/bus/usb/devices/$DEV/power/level'. And one has to have
CONFIG_USB_SUSPEND=y to do this.

On Windows and Mac OS, `safely remove this device' function effectly
turns it into `suspend' mode, and it's light off.

You have obviously tested only Windows XP, because Vista doesn't cut the power for at least some USB devices. And congratulations for obtaining a Vista-incompatible hard drive (of course, joking).

BTW, does the "eject /dev/$DEV" command help?

--
Alexander E. Patrakov

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