Re: [PATCH v3] leds: Introduce userspace leds driver

From	Pavel Machek <pavel@ucw.cz>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3] leds: Introduce userspace leds driver
Date	2016-09-16 08:00 +0200
Message-ID	<shUlP-ud-5@gated-at.bofh.it> (permalink)
References	(1 earlier) <sguD8-It-15@gated-at.bofh.it> <sguD8-It-13@gated-at.bofh.it> <shEAp-7rV-19@gated-at.bofh.it> <shGiS-8jb-53@gated-at.bofh.it> <shGVz-ku-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hi!

+The current brightness is found by reading a single byte from the
character
+device. Values are unsigned: 0 to 255. Reading does not block and
always returns
+the most recent brightness value. The device node can also be polled
to notify
+when the brightness value changes.

What is going on there? We have O_NONBLOCK, user should be able to
select if he wants blocking behaviour or not.

And yes, there's interface for creating a LED, but not one for
deleting it?

And... how is it going to work with multiple LEDs? Userspace gets
single bytes with brightness. How does it know to which LED the
brightness belongs?

Thanks,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Thread

[PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-09 19:00 +0200
  Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-09 22:50 +0200
  Re: [PATCH v3] leds: Introduce userspace leds driver Jacek Anaszewski <j.anaszewski@samsung.com> - 2016-09-12 10:20 +0200
    Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-12 17:00 +0200
    Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-15 15:10 +0200
      Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-15 15:40 +0200
        Re: [PATCH v3] leds: Introduce userspace leds driver Jacek Anaszewski <j.anaszewski@samsung.com> - 2016-09-15 17:00 +0200
          Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-16 08:20 +0200
      Re: [PATCH v3] leds: Introduce userspace leds driver Jacek Anaszewski <j.anaszewski@samsung.com> - 2016-09-15 17:00 +0200
        Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-15 17:40 +0200
          Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-15 17:40 +0200
          Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-16 08:00 +0200
            Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-16 17:40 +0200
          Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-16 08:00 +0200
            Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-16 17:20 +0200
          Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-16 08:10 +0200
            Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-16 17:50 +0200
        Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-15 18:40 +0200
          Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-16 08:00 +0200
            Re: [PATCH v3] leds: Introduce userspace leds driver Jacek Anaszewski <j.anaszewski@samsung.com> - 2016-09-16 09:10 +0200
              Re: [PATCH v3] leds: Introduce userspace leds driver David Lechner <david@lechnology.com> - 2016-09-16 17:20 +0200
                Re: [PATCH v3] leds: Introduce userspace leds driver Pavel Machek <pavel@ucw.cz> - 2016-09-16 21:40 +0200

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