Messages in this thread | | | Date | Thu, 3 Nov 2005 10:59:38 +0100 | From | Pavel Machek <> | Subject | Re: best way to handle LEDs |
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Hi!
> > > > yellow off: not charging > > > > yellow on: charging > > > > yellow fast blink: charge error > > > > > > > > I think even slow blinking was used somewhere. I have some code from > > > > John Lenz (attached); it uses sysfs interface, exports led collor, and > > > > allows setting different frequencies. > > > > > > > > Is that acceptable, or should some other interface be used? > > > > > > IMHO reducing digital outputs to LEDs goes not far enough. All System- > > > on-Chip CPUs have General Purpose I/O pins today, which can act as > > > inputs or outputs and may be used for LEDs, matrix keyboard lines, > > > > We have some leds that are *not* on GPIO pins (like driven by > > ACPI). We'd like to support those, too. > > I though ACPI was software? These LEDs have to be driven by some hardware, > right?
Right, but you don't know by *which* hardware. Only ACPI AML code knows. So from linux POW, they are handled by ACPI.
It may even trap to SMM BIOS. -- 64 bytes from 195.113.31.123: icmp_seq=28 ttl=51 time=448769.1 ms
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