linux-kernel - Re: [PATCH v2 18/18] auxdisplay: ht16k33: Add segment display LED support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAMuHMdXYLkoS7hTi1OZx7PMSCcfAR9YviJMN-x_dWpbz5KW+JA@mail.gmail.com>
Date:   Mon, 28 Jun 2021 11:21:08 +0200
From:   Geert Uytterhoeven <geert@...ux-m68k.org>
To:     Marek Behun <marek.behun@....cz>
Cc:     Robin van der Gracht <robin@...tonic.nl>,
        Rob Herring <robh+dt@...nel.org>,
        Miguel Ojeda <ojeda@...nel.org>,
        Paul Burton <paulburton@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Pavel Machek <pavel@....cz>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@...r.kernel.org>,
        linux-leds <linux-leds@...r.kernel.org>,
        "open list:BROADCOM NVRAM DRIVER" <linux-mips@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 18/18] auxdisplay: ht16k33: Add segment display LED support

Hi Marek,

On Fri, Jun 25, 2021 at 10:40 PM Marek Behun <marek.behun@....cz> wrote:
> On Fri, 25 Jun 2021 22:39:16 +0200
> Marek Behun <marek.behun@....cz> wrote:
> > On Fri, 25 Jun 2021 14:59:02 +0200
> > Geert Uytterhoeven <geert@...ux-m68k.org> wrote:
> > > Instantiate a single LED for a segment display.  This allows the user to
> > > control display brightness and blinking through the LED class API and
> > > triggers, and exposes the display color.
> > > The LED will be named "auxdisplay:<color>:backlight".
> >
> > What if there are multiple "auxdisplay"s ?
> > Doesn't this subsystem have IDs? So that you can use auxdisplayN for
> > device name, for example?
>
> Or if this driver creates a fbdev, maybe "fb<N>" for devicename?

This LED device is only registered when using the HT16K33 to drive
segment displays.
When driving a dot matrix display, the driver still use fbdev and
devm_backlight_device_register(), for backwards compatibility.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds