From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: Re: [PATCH v2 1/2] leds: Add Intel Cherry Trail Whiskey Cove PMIC LEDs Date: Sun, 17 Feb 2019 15:10:48 +0100 Message-ID: <81cc42f5-1f3d-c7f2-eb13-c2f8c4f9bfb4@redhat.com> References: <20190214230307.GA17358@amd> <2a5e2002-e5f1-6da3-8a43-317801b69657@redhat.com> <3d5407a7-9458-f071-a1d5-511b09678e20@gmail.com> <87a21c4e-8e5e-c180-2ff3-eb8170746e71@redhat.com> <80971bc3-1193-83ed-913a-12f6217016c8@gmail.com> <8a263266-a41f-c916-e990-02d04de9b5d0@gmail.com> <20190216193727.GA14305@amd> <7be63b6b-8d8d-90b8-fb17-d219b87a101f@redhat.com> <20190217000851.GA29803@amd> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190217000851.GA29803@amd> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Pavel Machek Cc: Jacek Anaszewski , Yauhen Kharuzhy , linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org List-Id: linux-leds@vger.kernel.org Hi, On 2/17/19 1:08 AM, Pavel Machek wrote: > >>> I don't pretend to fully understand it, _but_ hw_pattern should really >>> describe the pattern LED should do, not whether it reacts to charging >>> or not. >> >> Then we are back to step 1 of the discussion, that we need another >> mechanism outside of the trigger to select if the LED shows the configured >> pattern always, or only when the charger is on. > > Yep, sorry. > >> These really are 2 orthogonal settings, there is a pattern which can >> be set and the LED can either show that pattern always; or only when >> charging the battery. Note that the same pattern is used in both cases. >> >> This is why I previously suggested having a custom sysfs hardware_control >> attribute which selects between the "only show pattern when charging" >> modes ("hardware_control=1" or "always show the pattern mode" >> ("hardware_control=0"). > > I see... and yes, that would be the easiest solution. > > But somehow I see "this LED is controlled by charging state" as > primary and "it shows pulses instead of staying on" as secondary > eye-candy. > > This week there was another driver for charger LED.. but that one does > not do pulses. Ideally, we'd like consistent interface to the > userland. > > (To make it complex, the other driver supports things like: > LED solid on -- fully charged > LED blinking slowly -- charging > LED blinking fast -- charge error > LED off -- not charging). Something like that could be supported with my original hw_pattern proposal where we simply encode all of this in the hw-pattern file: tupple0: charging blinking_on_time tupple1: charging blinking_off_time tupple2: charging breathing_time tupple3: manual blinking_on_time tupple4: manual blinking_off_time tupple5: manual breathing_time So for this chip you mention, we do not need the breathing time (no breathing support), so we would get the following tupples: tupple0: not charging blinking_on_time tupple1: not charging blinking_off_time tupple2: slow charging blinking_on_time tupple3: slow charging blinking_off_time tupple4: fast charging blinking_on_time tupple5: fast charging blinking_off_time tupple6: charging error blinking_on_time tupple7: charging error blinking_off_time Where by solid on/off can be done by setting one of the blinking times to 0. Having hw_pattern ABIs like this where some of the tupples only activate on certain conditions might be better then a hardware_control sysfs file as it offers more flexibility. Regards, Hans