diff mbox series

[05/15] drm/vc4: hdmi: Restore cec physical address on reconnect

Message ID 20201210134648.272857-6-maxime@cerno.tech (mailing list archive)
State New, archived
Headers show
Series drm/vc4: hdmi: Add CEC support for the BCM2711 | expand

Commit Message

Maxime Ripard Dec. 10, 2020, 1:46 p.m. UTC
From: Dom Cobley <popcornmix@gmail.com>

Currently we call cec_phys_addr_invalidate on a hotplug deassert.
That may be due to a TV power cycling, or an AVR being switched
on (and switching edid).

This makes CEC unusable since our controller wouldn't have a physical
address anymore.

Set it back up again on the hotplug assert.

Fixes: 15b4511a4af6 ("drm/vc4: add HDMI CEC support")
Signed-off-by: Dom Cobley <popcornmix@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

Comments

Dave Stevenson Dec. 18, 2020, 2:21 p.m. UTC | #1
Hi  Maxime & Dom

On Thu, 10 Dec 2020 at 13:47, Maxime Ripard <maxime@cerno.tech> wrote:
>
> From: Dom Cobley <popcornmix@gmail.com>
>
> Currently we call cec_phys_addr_invalidate on a hotplug deassert.
> That may be due to a TV power cycling, or an AVR being switched
> on (and switching edid).
>
> This makes CEC unusable since our controller wouldn't have a physical
> address anymore.
>
> Set it back up again on the hotplug assert.
>
> Fixes: 15b4511a4af6 ("drm/vc4: add HDMI CEC support")
> Signed-off-by: Dom Cobley <popcornmix@gmail.com>
> Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> ---
>  drivers/gpu/drm/vc4/vc4_hdmi.c | 25 +++++++++++++++++--------
>  1 file changed, 17 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> index 28b78ea885ea..eff3bac562c6 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> @@ -136,20 +136,29 @@ static enum drm_connector_status
>  vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
>  {
>         struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
> +       bool connected = false;
>
>         if (vc4_hdmi->hpd_gpio) {
>                 if (gpio_get_value_cansleep(vc4_hdmi->hpd_gpio) ^
>                     vc4_hdmi->hpd_active_low)
> -                       return connector_status_connected;
> -               cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
> -               return connector_status_disconnected;
> -       }
> -
> -       if (drm_probe_ddc(vc4_hdmi->ddc))
> -               return connector_status_connected;
> -
> +                       connected = true;
> +       } else if (drm_probe_ddc(vc4_hdmi->ddc))
> +               connected = true;
>         if (HDMI_READ(HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)

This needs to become an "else if(...".
It used to be that all the other paths would return, so were mutually
exclusive to this. Now they set a thing and keep going we need to
avoid reading the register should there be a HPD gpio or the ddc probe
succeeds.
Memory says that otherwise Pi3 always reports connected.

I fixed this in a downstream patch already -
https://github.com/raspberrypi/linux/commit/d345caec1e9b2317b9cd7eb5b92ae453a0d3e98c

Otherwise fine.

  Dave

> +               connected = true;
> +       if (connected) {
> +               if (connector->status != connector_status_connected) {
> +                       struct edid *edid = drm_get_edid(connector, vc4_hdmi->ddc);
> +
> +                       if (edid) {
> +                               cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid);
> +                               vc4_hdmi->encoder.hdmi_monitor = drm_detect_hdmi_monitor(edid);
> +                               drm_connector_update_edid_property(connector, edid);
> +                               kfree(edid);
> +                       }
> +               }
>                 return connector_status_connected;
> +       }
>         cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
>         return connector_status_disconnected;
>  }
> --
> 2.28.0
>
Dave Stevenson Dec. 18, 2020, 2:45 p.m. UTC | #2
On Fri, 18 Dec 2020 at 14:21, Dave Stevenson
<dave.stevenson@raspberrypi.com> wrote:
>
> Hi  Maxime & Dom
>
> On Thu, 10 Dec 2020 at 13:47, Maxime Ripard <maxime@cerno.tech> wrote:
> >
> > From: Dom Cobley <popcornmix@gmail.com>
> >
> > Currently we call cec_phys_addr_invalidate on a hotplug deassert.
> > That may be due to a TV power cycling, or an AVR being switched
> > on (and switching edid).
> >
> > This makes CEC unusable since our controller wouldn't have a physical
> > address anymore.
> >
> > Set it back up again on the hotplug assert.
> >
> > Fixes: 15b4511a4af6 ("drm/vc4: add HDMI CEC support")
> > Signed-off-by: Dom Cobley <popcornmix@gmail.com>
> > Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> > ---
> >  drivers/gpu/drm/vc4/vc4_hdmi.c | 25 +++++++++++++++++--------
> >  1 file changed, 17 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> > index 28b78ea885ea..eff3bac562c6 100644
> > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> > @@ -136,20 +136,29 @@ static enum drm_connector_status
> >  vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
> >  {
> >         struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
> > +       bool connected = false;
> >
> >         if (vc4_hdmi->hpd_gpio) {
> >                 if (gpio_get_value_cansleep(vc4_hdmi->hpd_gpio) ^
> >                     vc4_hdmi->hpd_active_low)
> > -                       return connector_status_connected;
> > -               cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
> > -               return connector_status_disconnected;
> > -       }
> > -
> > -       if (drm_probe_ddc(vc4_hdmi->ddc))
> > -               return connector_status_connected;
> > -
> > +                       connected = true;
> > +       } else if (drm_probe_ddc(vc4_hdmi->ddc))
> > +               connected = true;
> >         if (HDMI_READ(HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)
>
> This needs to become an "else if(...".
> It used to be that all the other paths would return, so were mutually
> exclusive to this. Now they set a thing and keep going we need to
> avoid reading the register should there be a HPD gpio or the ddc probe
> succeeds.
> Memory says that otherwise Pi3 always reports connected.
>
> I fixed this in a downstream patch already -
> https://github.com/raspberrypi/linux/commit/d345caec1e9b2317b9cd7eb5b92ae453a0d3e98c
>
> Otherwise fine.
>
>   Dave
>
> > +               connected = true;
> > +       if (connected) {
> > +               if (connector->status != connector_status_connected) {
> > +                       struct edid *edid = drm_get_edid(connector, vc4_hdmi->ddc);
> > +
> > +                       if (edid) {
> > +                               cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid);
> > +                               vc4_hdmi->encoder.hdmi_monitor = drm_detect_hdmi_monitor(edid);
> > +                               drm_connector_update_edid_property(connector, edid);

Actually looking at this again in the context of the other changes, do
we need to call drm_connector_update_edid_property() here?

We've just called drm_get_edid() to get the edid, and that calls
drm_connector_update_edid_property() as well [1]
Updating vc4_hdmi->encoder.hdmi_monitor may be necessary. It's
otherwise done in vc4_hdmi_connector_get_modes, which I sort of expect
to be called almost immediately by the framework when connector_detect
returns "connected". I haven't checked if that is guaranteed though.

vc4_hdmi_connector_get_modes also includes a manual call to
drm_connector_update_edid_property after having just called
drm_get_edid, so that one feels redundant too.

  Dave

[1] https://elixir.bootlin.com/linux/v5.10/source/drivers/gpu/drm/drm_edid.c#L2059

> > +                               kfree(edid);
> > +                       }
> > +               }
> >                 return connector_status_connected;
> > +       }
> >         cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
> >         return connector_status_disconnected;
> >  }
> > --
> > 2.28.0
> >
Maxime Ripard Jan. 11, 2021, 10:29 a.m. UTC | #3
Hi Dave,

Thanks for your review

On Fri, Dec 18, 2020 at 02:45:54PM +0000, Dave Stevenson wrote:
> On Fri, 18 Dec 2020 at 14:21, Dave Stevenson
> <dave.stevenson@raspberrypi.com> wrote:
> >
> > Hi  Maxime & Dom
> >
> > On Thu, 10 Dec 2020 at 13:47, Maxime Ripard <maxime@cerno.tech> wrote:
> > >
> > > From: Dom Cobley <popcornmix@gmail.com>
> > >
> > > Currently we call cec_phys_addr_invalidate on a hotplug deassert.
> > > That may be due to a TV power cycling, or an AVR being switched
> > > on (and switching edid).
> > >
> > > This makes CEC unusable since our controller wouldn't have a physical
> > > address anymore.
> > >
> > > Set it back up again on the hotplug assert.
> > >
> > > Fixes: 15b4511a4af6 ("drm/vc4: add HDMI CEC support")
> > > Signed-off-by: Dom Cobley <popcornmix@gmail.com>
> > > Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> > > ---
> > >  drivers/gpu/drm/vc4/vc4_hdmi.c | 25 +++++++++++++++++--------
> > >  1 file changed, 17 insertions(+), 8 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> > > index 28b78ea885ea..eff3bac562c6 100644
> > > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> > > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> > > @@ -136,20 +136,29 @@ static enum drm_connector_status
> > >  vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
> > >  {
> > >         struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
> > > +       bool connected = false;
> > >
> > >         if (vc4_hdmi->hpd_gpio) {
> > >                 if (gpio_get_value_cansleep(vc4_hdmi->hpd_gpio) ^
> > >                     vc4_hdmi->hpd_active_low)
> > > -                       return connector_status_connected;
> > > -               cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
> > > -               return connector_status_disconnected;
> > > -       }
> > > -
> > > -       if (drm_probe_ddc(vc4_hdmi->ddc))
> > > -               return connector_status_connected;
> > > -
> > > +                       connected = true;
> > > +       } else if (drm_probe_ddc(vc4_hdmi->ddc))
> > > +               connected = true;
> > >         if (HDMI_READ(HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)
> >
> > This needs to become an "else if(...".
> > It used to be that all the other paths would return, so were mutually
> > exclusive to this. Now they set a thing and keep going we need to
> > avoid reading the register should there be a HPD gpio or the ddc probe
> > succeeds.
> > Memory says that otherwise Pi3 always reports connected.
> >
> > I fixed this in a downstream patch already -
> > https://github.com/raspberrypi/linux/commit/d345caec1e9b2317b9cd7eb5b92ae453a0d3e98c
> >
> > Otherwise fine.
> >
> >   Dave
> >
> > > +               connected = true;
> > > +       if (connected) {
> > > +               if (connector->status != connector_status_connected) {
> > > +                       struct edid *edid = drm_get_edid(connector, vc4_hdmi->ddc);
> > > +
> > > +                       if (edid) {
> > > +                               cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid);
> > > +                               vc4_hdmi->encoder.hdmi_monitor = drm_detect_hdmi_monitor(edid);
> > > +                               drm_connector_update_edid_property(connector, edid);
> 
> Actually looking at this again in the context of the other changes, do
> we need to call drm_connector_update_edid_property() here?
> 
> We've just called drm_get_edid() to get the edid, and that calls
> drm_connector_update_edid_property() as well [1]

Yeah, you're right I'll drop it

> Updating vc4_hdmi->encoder.hdmi_monitor may be necessary. It's
> otherwise done in vc4_hdmi_connector_get_modes, which I sort of expect
> to be called almost immediately by the framework when connector_detect
> returns "connected". I haven't checked if that is guaranteed though.
> 
> vc4_hdmi_connector_get_modes also includes a manual call to
> drm_connector_update_edid_property after having just called
> drm_get_edid, so that one feels redundant too.

.get_modes is called in drm_helper_probe_single_connector_modes, which
is usually the helper set in .fill_modes. .fill_modes seems to only be
called when either DRM_IOCTL_MODE_GETCONNECTOR is called, or when the
connector status is forced through sysfs, so it doesn't look like it's
done automatically.

I'm not sure we need to set hdmi_monitor though, it's only used to
configure the display related side, and that can't happen without
get_modes being called.

Maxime
diff mbox series

Patch

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 28b78ea885ea..eff3bac562c6 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -136,20 +136,29 @@  static enum drm_connector_status
 vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
 {
 	struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
+	bool connected = false;
 
 	if (vc4_hdmi->hpd_gpio) {
 		if (gpio_get_value_cansleep(vc4_hdmi->hpd_gpio) ^
 		    vc4_hdmi->hpd_active_low)
-			return connector_status_connected;
-		cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
-		return connector_status_disconnected;
-	}
-
-	if (drm_probe_ddc(vc4_hdmi->ddc))
-		return connector_status_connected;
-
+			connected = true;
+	} else if (drm_probe_ddc(vc4_hdmi->ddc))
+		connected = true;
 	if (HDMI_READ(HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)
+		connected = true;
+	if (connected) {
+		if (connector->status != connector_status_connected) {
+			struct edid *edid = drm_get_edid(connector, vc4_hdmi->ddc);
+
+			if (edid) {
+				cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid);
+				vc4_hdmi->encoder.hdmi_monitor = drm_detect_hdmi_monitor(edid);
+				drm_connector_update_edid_property(connector, edid);
+				kfree(edid);
+			}
+		}
 		return connector_status_connected;
+	}
 	cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
 	return connector_status_disconnected;
 }