Re: DRM/panel: Bringing Linux DRM Display Panel support in the modern age

Hi,

On Tue, May 26, 2026 at 09:41:18AM +0200, Neil Armstrong wrote:
> Since the introduction of the first Samsung DSI panel, the Linux DRM panel
> API has been a crucial piece of software for enabling displays across
> diverse architectures, but it has not evolved alongside modern graphics stacks.
> Currently, the API lacks atomic DRM API support and the ability to adapt
> power setups during mode changes.
> Furthermore, it fails to support advanced Display Driver IC (DDIC) features
> that modern hardware heavily relies on, including:
> - Standby and advanced power states
> - Advanced color management
> - Dynamic rate switching
> - Command mode self-refresh
> 
> This lack of evolution has led to severe fragmentation between
> upstream and vendor downstream trees for advanced devices support,
> creating a heavy maintenance burden and making native hardware support
> incredibly difficult.
> 
> The goal would be to outline these architectural limitations and
> trigger a discussion on how to collaboratively modernize the panel
> API. By standardizing advanced DDIC capabilities and fully embracing
> the atomic DRM API, we hope to establish a unified path forward for
> the entire Linux community.

I acknowledge it might sound a bit like "let's burn the whole thing to
the ground", but what you just described sounds an awful lot like what
the bridge API already does.

Let's acknowledge that drm_bridge isn't just about bridge anymore, make
panels bridges, and we're done.

The main problem with panels imo is how obscure they are, and are pretty
much fire-and-forget for panel vendors, so they have no incentive to
spend time upstreaming.

It really feels like a similar position compared to what HID was, and I
wonder if doing a dumb bridge driver for panels with ebpf support so we
can put all the panel quirks in userspace like HID-BPF would be the way
forward.

Maxime

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