Re: Linux support for a 7 segment LED display

From: Chris Packham
Date: Mon Feb 19 2024 - 15:08:42 EST



On 20/02/24 04:34, Pavel Machek wrote:
> Hi!
>
>> I'm looking for something that I figured must exists but maybe it's so
>> niche that no-one has bothered to upstream a driver for it.
>>
>> I have a requirement to support a 7-segment LED display[1] (one that can
>> display a single digit from 0-9). Hardware wise it's just a bunch of
>> individual GPIOs connected to each segment (plus an extra one for a
>> dot). I can't see anything obvious in drivers/leds but maybe I'm looking
>> in the wrong place. Or maybe it's the kind of thing on PC hardware that
>> is just driven by the BIOS without the operating system knowing about it.
> Look at drivers/auxdisplay. I believe we have segment displays there.

Thanks for the pointer. I found ht16k33.c (and
drivers/input/misc/yealink.c) which have support for 7 segment displays.
Still not quite what I'd need to glue it together with GPIOs but I can
see the direction one might head.