Thank you for your contribution! Sashiko AI review found 1 potential issue(s) 
to consider:

Pre-existing issues:
- [High] Early HPD interrupt can cause a NULL pointer dereference of 
`hdmi->bridge.dev` if it fires before `drm_bridge_attach` completes.
--

commit 1a1229643b989df67626f64f580add186cebd6ed
Author: Michal Wilczynski <[email protected]>

drm/bridge: inno-hdmi: Allow the register map to come from a parent
    
On some SoCs the HDMI controller does not own its register window. The
StarFive JH7110 documents one 64 KB block, u0_hdmitx, that holds both
the controller and the PHY, so the parent device maps it and owns the
regmap while the two children share it.

> diff --git a/drivers/gpu/drm/bridge/inno-hdmi.c 
> b/drivers/gpu/drm/bridge/inno-hdmi.c
> index aab474740f7f5..8bd7717611804 100644
> --- a/drivers/gpu/drm/bridge/inno-hdmi.c
> +++ b/drivers/gpu/drm/bridge/inno-hdmi.c
[ ... ]
> @@ -1095,9 +1110,19 @@ struct inno_hdmi *inno_hdmi_probe(struct 
> platform_device *pdev,
>       hdmi->dev = dev;
>       hdmi->plat_data = plat_data;
>  
> -     hdmi->regs = devm_platform_ioremap_resource(pdev, 0);
> -     if (IS_ERR(hdmi->regs))
> -             return ERR_CAST(hdmi->regs);
> +     /*
> +      * On platforms where the controller shares a register space with
> +      * other blocks, the parent owns the regmap. Fall back to mapping
> +      * our own resource where it does not.
> +      */
> +     if (dev->parent)
> +             hdmi->regmap = dev_get_regmap(dev->parent, NULL);
> +
> +     if (!hdmi->regmap) {
> +             hdmi->regs = devm_platform_ioremap_resource(pdev, 0);
> +             if (IS_ERR(hdmi->regs))
> +                     return ERR_CAST(hdmi->regs);
> +     }
>  
>       hdmi->pclk = devm_clk_get_enabled(hdmi->dev, "pclk");
>       if (IS_ERR(hdmi->pclk)) {

[Severity: High]
This is a pre-existing issue, but could this code trigger a NULL pointer
dereference if the hotplug interrupt fires early?

Looking at the rest of inno_hdmi_probe(), the hardware interrupt is unmuted
in inno_hdmi_init_hw(), and then the handler is registered:

    inno_hdmi_init_hw(hdmi);
    ...
    ret = devm_request_threaded_irq(dev, irq, inno_hdmi_hardirq,
                                    inno_hdmi_irq, IRQF_SHARED,
                                    dev_name(dev), hdmi);

If a cable is already connected or plugged in at this exact moment, the
interrupt can fire immediately. The threaded handler inno_hdmi_irq() will
then execute:

    drm_helper_hpd_irq_event(hdmi->bridge.dev);

However, hdmi->bridge.dev appears to be NULL at this point, as it is only
populated later when the upstream display controller calls
drm_bridge_attach().

Is there something preventing this race condition, or should the IRQ handler
registration be deferred?

-- 
Sashiko AI review ยท 
https://sashiko.dev/#/patchset/[email protected]?part=8

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