Re: [GIT PULL] LED updates

On Thu, 2008-02-07 at 19:38 -0200, Henrique de Moraes Holschuh wrote:
On Thu, 07 Feb 2008, Richard Purdie wrote:
Márton Németh:
leds: Add support for hardware accelerated LED flashing
leds: hw acceleration for Clevo mail LED driver

This one has a loose end: when you call brightness_set on a led with
hardware flash acceleration, you will leave the trigger armed, BUT the led
won't blink anymore. That's just wrong.

Agreed.

Either we should always remove *any* (hardware accelerated or not!) active
trigger when a write to brightness_set is done, or the stuff about "calling
brightness_set will disable the hardware accelerated blink" has to go.

I personally prefer that we would always remove any active trigger if
brightness_set is to be called. IMHO, it is neater, and it is also the
least-surprise-behaviour from an user perspective with the LED_OFF:LED_FULL
triggers we have right now.

Even without the hardware acceleration, a user write to set_brightness
leaves any active trigger active and isn't really intuitive or right
either.

Which one will be? If it is "remove any active trigger", I'd not mind
writing the patch.

I'll accept a patch for that :).

Richard Purdie:
leds: Standardise LED naming scheme

This one causes trouble (at least on 2.6.23 -- I backported the patch) due
to the 20-byte length limit on sysfs names. I had to use "tp::<somecrap>"
instead of "thinkpad::<somecrap>" to name LEDs, and still had to reduce
ultrabase_battery to ultrabase_batt :-)

Anyway, IMHO, the LED function should come first, and we should not even
need the led driver name anywhere. In case of clashes in the class sysfs
dir, just tack a .# to the end or somesuch. The device the LED is tied to
already differentiates them. That would save a lot of chars for something
much more useful (the function).

Ouch, I'm looking into this. I wish I'd known about it earlier. I agree
function is more important but didn't want to break the existing
convention. I guess this limitation comes from the kobjects involved...

Richard




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