mbox series

[v3,0/4] auxdisplay: 7 segment LED display

Message ID 20240301014203.2033844-1-chris.packham@alliedtelesis.co.nz
Headers
Series auxdisplay: 7 segment LED display |

Message

Chris Packham March 1, 2024, 1:41 a.m. UTC 
  This series adds a driver for a 7 segment LED display.

I haven't had a chance to look at the gpio changes that'd be required to
have multiple characters as subnodes. I wanted to get the code that
addressed Andy and Rob's comments out before my weekend.
--
[1] - https://lore.kernel.org/lkml/2a8d19ee-b18b-4b7c-869f-7d601cea30b6@alliedtelesis.co.nz/

Chris Packham (4):
  auxdisplay: Add 7-segment LED display driver
  dt-bindings: auxdisplay: Add bindings for generic 7-segment LED
  ARM: dts: marvell: Add 7-segment LED display on x530
  ARM: dts: marvell: Indicate USB activity on x530

 .../bindings/auxdisplay/gpio-7-segment.yaml   |  42 ++++++
 .../boot/dts/marvell/armada-385-atl-x530.dts  |  22 +++-
 drivers/auxdisplay/Kconfig                    |  10 ++
 drivers/auxdisplay/Makefile                   |   1 +
 drivers/auxdisplay/seg-led-gpio.c             | 122 ++++++++++++++++++
 5 files changed, 196 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/auxdisplay/gpio-7-segment.yaml
 create mode 100644 drivers/auxdisplay/seg-led-gpio.c

Comments

Geert Uytterhoeven March 4, 2024, 9:57 a.m. UTC | #1 
Hi Andy,

On Sun, Mar 3, 2024 at 9:43 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Sun, Mar 3, 2024 at 11:48 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Fri, Mar 1, 2024 at 7:24 PM Andy Shevchenko <andy@kernel.org> wrote:
> > > The problem here as I see it is the future decision on how DP should
> > > behave like.  If you put this into DT, we will to support this to the end
> > > of the platform.
> >
> > As there exist 7-seg displays (and wirings) with and without DP,
> > the 7-seg driver and DT bindings should handle both cases.  How to
> > wire/use the DP LED is up to the hardware designer / DTS writer.
>
> Right. But my personal statistics for now is: 100% has DP (out of
> about a dozen of different chip + LED combinations). What's yours?

It's indeed hard to find contemporary 7-segment LED assemblies that
lack the DP.  But they do exist[1].  There's also no guarantee that the
DP is wired.
And don't forget custom or home-built assemblies using discrete LEDs,
especially for huge displays (e.g. using one LED-strip per segment).
So IMHO it would be a bad idea to make the DP mandatory.

[1] https://www.alibaba.com/product-detail/CC-CA-188-led-display-0_60626228913.html

Gr{oetje,eeting}s,

                        Geert