Messages in this thread | | | Date | Fri, 9 Jan 2015 18:40:58 +0100 | From | Pavel Machek <> | Subject | Re: [PATCH/RFC v10 02/19] Documentation: leds: Add description of LED Flash class extension |
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Hi!
> The documentation being added contains overall description of the > LED Flash Class and the related sysfs attributes. > > Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com> > Acked-by: Kyungmin Park <kyungmin.park@samsung.com> > Cc: Bryan Wu <cooloney@gmail.com> > Cc: Richard Purdie <rpurdie@rpsys.net>
> +In order to enable support for flash LEDs CONFIG_LEDS_CLASS_FLASH symbol > +must be defined in the kernel config. A flash LED driver must register > +in the LED subsystem with led_classdev_flash_register function to gain flash > +related capabilities. > + > +There are flash LED devices which can control more than one LED and allow for > +strobing the sub-leds synchronously. A LED will be strobed synchronously with > +the one whose identifier is written to the flash_sync_strobe sysfs attribute. > +The list of available sub-led identifiers can be read from the
sub-LED?
> + - flash_fault - bitmask of flash faults that may have occurred > + possible flags are: > + * 0x01 - flash controller voltage to the flash LED has exceeded > + the limit specific to the flash controller > + * 0x02 - the flash strobe was still on when the timeout set by > + the user has expired; not all flash controllers may > + set this in all such conditions > + * 0x04 - the flash controller has overheated > + * 0x08 - the short circuit protection of the flash controller > + has been triggered > + * 0x10 - current in the LED power supply has exceeded the limit > + specific to the flash controller > + * 0x20 - the flash controller has detected a short or open > + circuit condition on the indicator LED > + * 0x40 - flash controller voltage to the flash LED has been > + below the minimum limit specific to the flash > + * 0x80 - the input voltage of the flash controller is below > + the limit under which strobing the flash at full > + current will not be possible. The condition persists > + until this flag is no longer set > + * 0x100 - the temperature of the LED has exceeded its allowed > + upper limit
Did not everyone agree that text strings are preferable to bitmasks?
Pavel
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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