Re: [PATCH v11 2/3] drm/bridge: imx: Add i.MX93 parallel display format configuration support

[Liu Ying]

On Tue, Mar 10, 2026 at 12:53:07PM +0100, Luca Ceresoli wrote:
> Hi Liu, Marco,
> 
> On Tue Mar 10, 2026 at 3:57 AM CET, Liu Ying wrote:
>> Hi Marco, Luca,
>>
>> On Tue, Mar 03, 2026 at 11:34:27AM +0100, Marco Felsch wrote:
>>
>> [...]
>>
>>> +	next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
>>> +	if (IS_ERR(next_bridge))
>>> +		return dev_err_probe(dev, PTR_ERR(next_bridge),
>>> +				     "failed to get next bridge\n");
>>> +	pdfc->dev = dev;
>>> +	pdfc->bridge.of_node = dev->of_node;
>>> +	pdfc->bridge.type = DRM_MODE_CONNECTOR_DPI;
>>> +	pdfc->bridge.next_bridge = next_bridge;
>>
>> When I was reviewing another patch[1], I was aware of the necessity of
>> calling drm_bridge_get() for next_bridge to balance the next bridge's
>> refcount put from __drm_bridge_free() for this bridge.  I'd be good if
>> Luca may confirm this is correct.  Sorry for bringing this up late.
> 
> Indeed you have a good point.
> 
> After re-checking devm_drm_of_get_bridge(), as I wrote on the other thread
> you pointed to, you should call drm_bridge_get():

Thanks for the confirmation.

> 
> -	pdfc->bridge.next_bridge = next_bridge;
> +	pdfc->bridge.next_bridge = drm_bridge_get(next_bridge);
> 
> Marco, you can keep my R-by if you resend with just this change.

Marco, care to resend with just this change?

> 
> Sorry about the confusion here.
> 
> As mention on the other thread, devm_drm_of_get_bridge() is unable to
> support bridge hotplug. So it should be deprecated, but as of now there is
> no alternative.
> 
> Luca
> 
> --
> Luca Ceresoli, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com/

-- 
Regards,
Liu Ying