Messages in this thread | | | From | Kyle Moffett <> | Subject | Re: Add a "enable" sysfs attribute to the pci devices to allow userspace (Xorg) to enable devices without doing foul direct access | Date | Mon, 8 May 2006 10:26:52 -0400 |
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On May 7, 2006, at 09:12:01, Pavel Machek wrote: >>> It has everything to do with the 'enable' file. The 'enable' file >>> lets you change the state of the hardware without an ownership >>> mechanism. Other device users will not be notified of the state >>> change. Since the other users can't be sure of the state of the >>> hardware when they are activated, they will have to reload their >>> state into the hardware on every activation. >> >> you seem to miss the fact that this can be done now without the >> enable flag, setpci can be used to disable the BARs, again the >> enable flag doesn't change that.... > > ...well, when you launch setpci, you are firmly in 'unsupported' > land. While 'enable' sounds like something where users expect it > to be supported.
*Especially* since there are a number of users (including myself) who have tendencies to go wandering around sysfs tinkering with the available values. Not having seen this thread, I would have had no problem doing "echo -n 0 >enable" on some device thinking that it was a fairly standard way to turn off the power to my soundcard when I'm not using it, and likely result in a kernel panic because I suddenly disabled the BARs on the device out from under the driver.
Cheers, Kyle Moffett
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