USB and suspend. Will it still charge?
andy at openmoko.com
Wed Apr 23 09:08:21 CEST 2008
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Somebody in the thread at some point said:
| On Tue, 22 Apr 2008 15:42:36 +0100 Andy Green <andy at openmoko.com> babbled:
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|> Somebody in the thread at some point said:
|> | This afternoon I recognized my laptop throwing a note about "USB device
|> | detached" when Freerunner goes suspend.
|> | Raster knows, at least Windows definitely will power down the
|> | when it sees USB-disconnect.
|> | Maybe we should investigate this, and should clock down the CPU and
|> shut off
|> | LCM, but not go to suspend while charging.
|> | I should mention I'm not even sure Freerunner did charge at all at this
|> | moment, just in case this makes a difference.
|> What's the actual concern there? If it is to do with missing charging
|> state change, the PMU throws an interrupt to the CPU on USB connector
|> insertion and removal, AFAIK these will cause wake.
| concern is:
| we plug in, phone wakes. phone gets bored. phone goes to sleep. uspend
| pc detects device removal. pc powers down usb port. phone does not
| from usb. no charging happens.
Normal PC doesn't "power down USB port" I think you'll find. The port
has to be powered to detect next device insertion. You can confirm with
one of these USB reading lamps for example that have no smarts inside.
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