Re: Patches still in the queue
Oliver Neukum <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
Am Dienstag, 15. Mai 2007 23:49 schrieb Alan Stern: > On Tue, 15 May 2007, Oliver Neukum wrote: > I think we're getting off the point here. Suppose the usbhid driver > gets a powerloss_resume call for a mouse. What do you want it to do > that we aren't already doing? Nothing. My point was that powerloss_resume() would be a benefit for every driver. Only that some drivers can't implement it. > > > Not at all -- we should fix the driver! If it claims to support > > > autosuspend then it should also be able to handle reset_resume without > > > any need for rebinding. > > > > Why? Or rather which kind? Quirky devices are very rare. Why would > > all drivers need to handle that? As for powerloss, a printer driver can > > never do that, as it cannot restore the printer's setting. Likewise anything > > claimed by usbfs. There are other examples. > > Two separate issues: > > reset_resume will happen only because of the quirk. But when it > happens during an autoresume, we cannot unbind the driver because we > don't own the device lock. So what do you want to do then? This would need a separate thread. But if a driver does not support reset_resume() and a device is quirky, why would you autosuspend in the first place? It seems to me that this issue arises only if reset_resume() returns an error. Is there a reason to treat this differently from resume() failing? On a system resume, we can unbind. > powerloss_resume will happen only when waking up from a system sleep, > and since it won't be an autoresume we will own the device lock. Hence > we will be able to rebind drivers. Good. This method can potentially find out that it is running on the wrong device. The others cannot. Regards Oliver ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel