Re: [PATCH v6 08/14] drm/rockchip: analogix_dp: Add support to get panel from the DP AUX bus

[Damon Ding <damon.ding@xxxxxxxxxxxxxx>]

Hi Lucas,

On 2025/2/8 3:42, Lucas Stach wrote:
> Hi Damon,
>
> Am Donnerstag, dem 23.01.2025 um 18:07 +0800 schrieb Damon Ding:
> > Move drm_of_find_panel_or_bridge() a little later and combine it with
> > component_add() into a new function rockchip_dp_link_panel(). The function
> > will serve as done_probing() callback of devm_of_dp_aux_populate_bus(),
> > aiding to support for obtaining the eDP panel via the DP AUX bus.
> >
> > If failed to get the panel from the DP AUX bus, it will then try the other
> > way to get panel information through the platform bus.
> The changes in this patch effectively revert 86caee745e45
> ("drm/rockchip: analogix_dp: allow to work without panel"). Please
> correct this in the next revision of this patchset.
>
> Regards,
> Lucas

Oh, I see. I will fix it in the next version.

> > Signed-off-by: Damon Ding <damon.ding@xxxxxxxxxxxxxx>
> >
> > ---
> >
> > Changes in v4:
> > - Use done_probing() to call drm_of_find_panel_or_bridge() and
> >    component_add() when getting panel from the DP AUX bus
> >
> > Changes in v5:
> > - Use the functions exported by the Analogix side to get the pointers of
> >    struct analogix_dp_plat_data and struct drm_dp_aux.
> > - Use dev_err() instead of drm_err() in rockchip_dp_poweron().
> >
> > Changes in v6:
> > - Keep drm_err() in rockchip_dp_poweron()
> > - Pass 'dp' in drm_...() rather than 'dp->drm_dev'
> > ---
> >   .../gpu/drm/rockchip/analogix_dp-rockchip.c   | 37 ++++++++++++++-----
> >   1 file changed, 28 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> > index 13f32aeea7ca..004b1b68d1cf 100644
> > --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> > +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> > @@ -393,11 +393,27 @@ static const struct component_ops rockchip_dp_component_ops = {
> >   	.unbind = rockchip_dp_unbind,
> >   };
> >   
> > +static int rockchip_dp_link_panel(struct drm_dp_aux *aux)
> > +{
> > +	struct analogix_dp_plat_data *plat_data = analogix_dp_aux_to_plat_data(aux);
> > +	struct rockchip_dp_device *dp = pdata_encoder_to_dp(plat_data);
> > +	int ret;
> > +
> > +	ret = drm_of_find_panel_or_bridge(dp->dev->of_node, 1, 0, &plat_data->panel, NULL);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = component_add(dp->dev, &rockchip_dp_component_ops);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return ret;
> > +}
> > +
> >   static int rockchip_dp_probe(struct platform_device *pdev)
> >   {
> >   	struct device *dev = &pdev->dev;
> >   	const struct rockchip_dp_chip_data *dp_data;
> > -	struct drm_panel *panel = NULL;
> >   	struct rockchip_dp_device *dp;
> >   	struct resource *res;
> >   	int i;
> > @@ -407,10 +423,6 @@ static int rockchip_dp_probe(struct platform_device *pdev)
> >   	if (!dp_data)
> >   		return -ENODEV;
> >   
> > -	ret = drm_of_find_panel_or_bridge(dev->of_node, 1, 0, &panel, NULL);
> > -	if (ret < 0 && ret != -ENODEV)
> > -		return ret;
> > -
> >   	dp = devm_kzalloc(dev, sizeof(*dp), GFP_KERNEL);
> >   	if (!dp)
> >   		return -ENOMEM;
> > @@ -434,7 +446,6 @@ static int rockchip_dp_probe(struct platform_device *pdev)
> >   
> >   	dp->dev = dev;
> >   	dp->adp = ERR_PTR(-ENODEV);
> > -	dp->plat_data.panel = panel;
> >   	dp->plat_data.dev_type = dp->data->chip_type;
> >   	dp->plat_data.power_on = rockchip_dp_poweron;
> >   	dp->plat_data.power_off = rockchip_dp_powerdown;
> > @@ -450,9 +461,17 @@ static int rockchip_dp_probe(struct platform_device *pdev)
> >   	if (IS_ERR(dp->adp))
> >   		return PTR_ERR(dp->adp);
> >   
> > -	ret = component_add(dev, &rockchip_dp_component_ops);
> > -	if (ret)
> > -		return ret;
> > +	ret = devm_of_dp_aux_populate_bus(analogix_dp_get_aux(dp->adp), rockchip_dp_link_panel);
> > +	if (ret) {
> > +		if (ret != -ENODEV) {
> > +			drm_err(dp, "failed to populate aux bus : %d\n", ret);
> > +			return ret;
> > +		}
> > +
> > +		ret = rockchip_dp_link_panel(analogix_dp_get_aux(dp->adp));
> > +		if (ret)
> > +			return ret;
> > +	}
> >   
> >   	return 0;
> >   }

Best regards
Damon