Re: [PATCH v6 07/10] drm/msm/dp: rework HPD handling

[Dmitry Baryshkov]

On Mon, May 25, 2026 at 03:51:15PM +0200, Konrad Dybcio wrote:
> On 5/24/26 12:33 PM, Dmitry Baryshkov wrote:
> > From: Jessica Zhang <jessica.zhang@xxxxxxxxxxxxxxxx>
> > 
> > Handling of the HPD events in the MSM DP driver is plagued with lots of
> > problems. It tries to work aside of the main DRM framework, handling the
> > HPD signals on its own. There are two separate paths, one for the HPD
> > signals coming from the DP HPD pin and another path for signals coming
> > from outside (e.g. from the Type-C AltMode). It lies about the connected
> > state, returning the link established state instead. It is not easy to
> > understand or modify it. Having a separate event machine doesn't add
> > extra clarity.
> > 
> > Drop the whole event machine. When the DP receives a HPD event, send it
> > to the DRM core. Then handle the events in the hpd_notify callback,
> > unifying paths for HPD signals.
> > 
> > Signed-off-by: Jessica Zhang <jessica.zhang@xxxxxxxxxxxxxxxx>
> > Tested-by: Val Packett <val@xxxxxxxxxxxx> # x1e80100-dell-latitude-7455
> > Tested-by: Yongxing Mou <yongxing.mou@xxxxxxxxxxxxxxxx> # Hamoa IOT EVK, QCS8300 Ride
> > Co-developed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> > ---
> 
> This is way too complex for me to grasp at once, so I have a couple nits
> 
> [...]
> 
> > +	drm_dbg_dp(dp->drm_dev, "After, type=%d\n",
> > +			dp->msm_dp_display.connector_type);
> 
> Most debug prints added in this patch have odd indent and some
> have vague messages

Correcting the identation. I'm not sure, which messages are vague.


-- 
With best wishes
Dmitry