Re: [PATCH v1 1/2] leds: aw200xx: support for hw pattern controllers

From: Pavel Machek
Date: Fri Jan 26 2024 - 18:24:36 EST


Hi!

> > This led-controller supports 3 pattern controllers for auto breathing or
> > group dimming control. Each pattern controller can work in auto
> > breathing or manual control mode. All breathing parameters including
> > rising/falling slope, on/off time, repeat times, min/max brightness
> > and so on are configurable.
> >
> > Signed-off-by: Martin Kurbanov <mmkurbanov@xxxxxxxxxxxxxxxxx>
> > ---
> > .../testing/sysfs-class-led-driver-aw200xx | 108 +++
> > Documentation/leds/leds-aw200xx.rst | 274 ++++++++
> > drivers/leds/leds-aw200xx.c | 649 ++++++++++++++++++
> > 3 files changed, 1031 insertions(+)
> > create mode 100644 Documentation/leds/leds-aw200xx.rst
>
> This interface is bananas. Exposing an entire register interface to
> sysfs does not sit will with me at all. When we add support to a sysfs
> class, we usually require it to be generic and work across all devices.
> Adding device specific interfaces is generally decried and to be
> avoided. Don't forget, once we commit something to sysfs, it becomes
> ABI and we have to support it forever.

If you do git grep hw_pattern, you should get pointers to qcom-lpg
driver that solves similar problem, with interface that should be
acceptable.

Best regards,
Pavel