Hi,
On Thu, 2007-05-31 at 17:53 +0200, Jan Kratochvil wrote:
> On Thu, 31 May 2007, Pavel Machek wrote:
> >> Led subsystem allows us to set brightness, but there is
> >> nothing like brightness on this device. So brightness is
> >> actually interpreted as the command (only values between
> >> 0 and 14 are accepted).
> >
> > Ugh, no, I do not think we want to do that.
>
> finally! I was surprised that it took so long before someone made objection to
> this.
:)
This hadn't gone unnoticed by me and I didn't like it either at first
however I had a look at the hardware specs and your summary below is
pretty accurate...
> I agree that interpreting brightness as command isn't nice. But what other
> options do I have?
> a) Do not use led subystem, and do everything on my own
> b) Do not allow user to change state of leds on this device
> c) Extend led subsystem to have something like command. But it is in
> contradiction with desired simplicity of led sybsystem.
Since the commands are so device specific and no new device will be the
same, I doubt this is worth doing (or possible) in a generic way so
you're back to a).
> d) Control leds via force feedback effect
> e) Make 4 leds available and use brightness 0 for off and 255 for on. But only
> one of them can be active at one time. And I'll give up some flashing effects.
If you expose 4 leds, you break the API badly as only one can be active.
That is worse than using the brightness parameter IMO.
> Well actually I don't like this options. Any suggestions? Thanks!
After consideration, I agree with your approach of using the brightness
and I don't have a better suggestion. Its not ideal but its a good
compromise since it doesn't really impose any limitations on your use of
the hardware but doesn't need a custom implementation which is the
alternative. The mode is still a kind of brightness setting if you twist
the definition a bit ;-).
Cheers,
Richard
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
