From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jacek Anaszewski Subject: Re: [PATCH 02/24] leds: core: Add support for composing LED class device names Date: Mon, 12 Nov 2018 17:01:59 +0100 Message-ID: <662c02ba-455b-e2bf-a5e2-ae3933161894@gmail.com> References: <1541542052-10081-1-git-send-email-jacek.anaszewski@gmail.com> <1541542052-10081-3-git-send-email-jacek.anaszewski@gmail.com> <20181111120234.GA28794@amd> <20181111201605.GA20160@amd> <57b77d4e-39a0-aaf2-5952-c2c25dc58593@gmail.com> <20181112103513.GB5695@amd> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181112103513.GB5695@amd> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Pavel Machek Cc: linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, robh@kernel.org, Baolin Wang , Daniel Mack , Dan Murphy , Linus Walleij , Oleh Kravchenko , Sakari Ailus , Simon Shields , Xiaotong Lu List-Id: linux-leds@vger.kernel.org Hi, On 11/12/2018 11:35 AM, Pavel Machek wrote: > Hi! > >>>> It's overcomplicating the naming again. In every case you can tweak >>>> the function name to eth0_link, eth1_link etc. >>> >>> Well, but in such case it would be good to keep existing scheme. >>> >>> My system looks like this: >>> >>> input16::capslock tpacpi::bay_active tpacpi::standby >>> input16::numlock tpacpi::dock_active tpacpi::thinklight >>> input16::scrolllock tpacpi::dock_batt tpacpi::thinkvantage >>> input5::capslock tpacpi::dock_status1 tpacpi::unknown_led >>> input5::numlock tpacpi::dock_status2 tpacpi::unknown_led2 >>> input5::scrolllock tpacpi:green:batt tpacpi::unknown_led3 >>> >>> I agree that we should get rid of "tpacpi:" part in some cases. But >>> it does not make sense to get rid of "input16:" part -- it tells you >>> if the LED is on USB or on built-in keyboard. >>> >>> Ideally, tpacpi::thinklight would be input5::frontlight (as it is >>> frontlight for the keyboard). >>> >>> Yes we should simplify, but it still needs to work in all cases. >> >> Well, label is not being removed. You still can use it an the old >> fashion, even when using new led_compose_name(). >> >> Maybe removing the description of the old LED naming from >> Documentation/leds/leds-class.txt was too drastic move. >> I'll keep it next to the new one, and only add a note that >> it is kept only for backwards compatibility. > > I agree that removing it is "just too drastic". > > But it is not just for backwards compatibility. See my examples above, > it is needed to tell which device the LED is asociated with, and it is > absolutely required for USB devices (for example). For USB devices there is already ledtrig-usbport available, which provides sysfs interface for defining and reading the usb ports, the status of which the LED indicates. Since the USB devices can be attached/removed dynamically, it would be impossible to reflect the associations in the LED class device name. > And even for "embedded" stuff like routers, we want eth0:green:link, > eth0:yellow:activity and not some kind of hack. eth0 is not something you can be certain of at the stage of defining DT node. > Ideally, colors would come from fixed list, functions would come from > fixed list, and device part would come from name used elsewhere in the > kernel. > > (And yes, it probably means we should have something in device tree to > link LED to its device. device = "name" would be good start...) Why would you need such link? -- Best regards, Jacek Anaszewski