From: David Laight <David.Laight@ACULAB.COM>
To: 'Linus Walleij' <linus.walleij@linaro.org>,
Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linux LED Subsystem <linux-leds@vger.kernel.org>,
"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
<devicetree@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Pavel Machek <pavel@ucw.cz>, Rob Herring <robh@kernel.org>,
Dmitry Torokhov <dtor@google.com>,
Guenter Roeck <linux@roeck-us.net>, Dan Murphy <dmurphy@ti.com>,
Baolin Wang <baolin.wang@linaro.org>,
Daniel Mack <daniel@zonque.org>,
Oleh Kravchenko <oleg@kaa.org.ua>,
Sakari Ailus <sakari.ailus@linux.intel.com>,
Simon Shields <simon@lineageos.org>
Subject: RE: [PATCH v5 05/26] leds: core: Add support for composing LED class device names
Date: Fri, 28 Jun 2019 13:30:30 +0000 [thread overview]
Message-ID: <643e3b10fe9d45b59ed063ffc6d578ff@AcuMS.aculab.com> (raw)
In-Reply-To: <CACRpkdYdqKZVKSaQB0THi=iZcRT04EKX2-85__Hw1f53o8vsuw@mail.gmail.com>
From: Linus Walleij
> Sent: 28 June 2019 09:46
...
> A problem with LEDs is that it invites bikeshedding because it is too
> relateable.
Bikeshedding leds :-)
It also isn't at all clear how to handle bi-colour and tri-colour leds.
ISTR the usual interface lets you set the brightness, but more often
leds are single brightness but multi-colour.
Eg the ethernet 'speed' led which is (usually) off/orange/green.
Changing the brightness either means changing the current or using PWM.
Both really require more hardware support than changing colours.
I've done some led driving (for a front panel) from a PLD (small FPGA).
As well as the obvious things I did:
- dim: 1/8th on at 80Hz.
- flash: 1/8th on at 4Hz.
- orange: 50-50 red-green at 80Hz on an RGB led.
There was also the 'ethernet activity' led which could either be driven
by the hardware, or forced on/off/flash by the driver.
If driven by the hardware, the software could read the current state.
None of this really fitted the Linux leds interface.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
next prev parent reply other threads:[~2019-06-28 13:30 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-09 19:07 [PATCH v5 00/26] Add generic support for composing LED class device name Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 01/26] leds: class: Improve LED and LED flash class registration API Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 02/26] dt-bindings: leds: Add LED_COLOR_ID definitions Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 03/26] dt-bindings: leds: Add LED_FUNCTION definitions Jacek Anaszewski
2019-11-15 13:01 ` Geert Uytterhoeven
2019-11-15 20:14 ` Jacek Anaszewski
2019-11-25 15:17 ` Pavel Machek
2019-06-09 19:07 ` [PATCH v5 04/26] dt-bindings: leds: Add properties for LED name construction Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 05/26] leds: core: Add support for composing LED class device names Jacek Anaszewski
2019-06-26 19:05 ` Jacek Anaszewski
2019-06-26 20:07 ` Oleh Kravchenko
2019-06-27 18:28 ` Jacek Anaszewski
2019-06-28 8:46 ` Linus Walleij
2019-06-28 13:30 ` David Laight [this message]
2019-07-03 22:05 ` Various LED complexities was " Pavel Machek
2019-07-03 22:00 ` Pavel Machek
2019-07-17 21:03 ` Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 06/26] dt-bindings: sc27xx-blt: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 07/26] leds: sc27xx-blt: Use generic support for composing LED names Jacek Anaszewski
2019-06-10 2:52 ` Baolin Wang
2019-06-09 19:07 ` [PATCH v5 08/26] dt-bindings: lt3593: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 09/26] leds: lt3593: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 10/26] dt-bindings: lp8860: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 11/26] leds: lp8860: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 12/26] dt-bindings: lm3692x: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 13/26] leds: lm3692x: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 14/26] dt-bindings: lm36010: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 15/26] leds: lm3601x: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 16/26] dt-bindings: cr0014114: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 17/26] leds: cr0014114: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 18/26] dt-bindings: aat1290: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 19/26] leds: aat1290: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 20/26] dt-bindings: as3645a: Add function and color properties Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 21/26] leds: as3645a: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:07 ` [PATCH v5 22/26] dt-bindings: leds-gpio: Add function and color properties Jacek Anaszewski
2019-06-09 19:08 ` [PATCH v5 23/26] leds: gpio: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:08 ` [PATCH v5 24/26] dt-bindings: an30259a: Add function and color properties Jacek Anaszewski
2019-06-09 19:08 ` [PATCH v5 25/26] leds: an30259a: Use generic support for composing LED names Jacek Anaszewski
2019-06-09 19:08 ` [PATCH v5 26/26] leds: Document standard LED functions Jacek Anaszewski
2019-07-18 11:03 ` Pavel Machek
2019-07-18 13:31 ` Jacek Anaszewski
2019-07-17 21:14 ` [PATCH v5 00/26] Add generic support for composing LED class device name Jacek Anaszewski
2019-07-18 10:52 ` Pavel Machek
2019-07-24 21:02 ` Jacek Anaszewski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=643e3b10fe9d45b59ed063ffc6d578ff@AcuMS.aculab.com \
--to=david.laight@aculab.com \
--cc=baolin.wang@linaro.org \
--cc=daniel@zonque.org \
--cc=devicetree@vger.kernel.org \
--cc=dmurphy@ti.com \
--cc=dtor@google.com \
--cc=jacek.anaszewski@gmail.com \
--cc=linus.walleij@linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-leds@vger.kernel.org \
--cc=linux@roeck-us.net \
--cc=oleg@kaa.org.ua \
--cc=pavel@ucw.cz \
--cc=robh@kernel.org \
--cc=sakari.ailus@linux.intel.com \
--cc=simon@lineageos.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).