diff mbox series

drm: Fire off KMS hotplug events if probe detect says the connector is connected

Message ID 20190418080929.22385-1-gwan-gyeong.mun@intel.com (mailing list archive)
State New, archived
Headers show
Series drm: Fire off KMS hotplug events if probe detect says the connector is connected | expand

Commit Message

Gwan-gyeong Mun April 18, 2019, 8:09 a.m. UTC
The hotplug detection routine of drm_helper_hpd_irq_event() can detect
changing of status of connector, but it can not detect changing of
properties of the connector.
e.g. changing of edid while suspend/resume, changing of dp lanes in dp aux.

Following scenario explains one of them; A detection of changing of edid.

 1) plug display device to a connector
 2) system suspend
 3) unplug 1)'s display device and plug the other display device to a
    connector
 4) system resume

To solve explained cases, It fires off KMS hotplug events if
drm_helper_probe_detect() says the connector is connected.

Testcase: igt/kms_chamelium/hdmi-edid-change-during-hibernate
Testcase: igt/kms_chamelium/hdmi-edid-change-during-suspend
Testcase: igt/kms_chamelium/dp-edid-change-during-hibernate
Testcase: igt/kms_chamelium/dp-edid-change-during-suspend

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Link: https://lists.freedesktop.org/archives/dri-devel/2019-April/214572.html
---
 drivers/gpu/drm/drm_probe_helper.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Daniel Vetter April 18, 2019, 8:28 a.m. UTC | #1
On Thu, Apr 18, 2019 at 11:09:29AM +0300, Gwan-gyeong Mun wrote:
> The hotplug detection routine of drm_helper_hpd_irq_event() can detect
> changing of status of connector, but it can not detect changing of
> properties of the connector.
> e.g. changing of edid while suspend/resume, changing of dp lanes in dp aux.
> 
> Following scenario explains one of them; A detection of changing of edid.
> 
>  1) plug display device to a connector
>  2) system suspend
>  3) unplug 1)'s display device and plug the other display device to a
>     connector
>  4) system resume
> 
> To solve explained cases, It fires off KMS hotplug events if
> drm_helper_probe_detect() says the connector is connected.
> 
> Testcase: igt/kms_chamelium/hdmi-edid-change-during-hibernate
> Testcase: igt/kms_chamelium/hdmi-edid-change-during-suspend
> Testcase: igt/kms_chamelium/dp-edid-change-during-hibernate
> Testcase: igt/kms_chamelium/dp-edid-change-during-suspend
> 
> Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>

This isn't at all what I suggested.
-Daniel

> Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> Link: https://lists.freedesktop.org/archives/dri-devel/2019-April/214572.html
> ---
>  drivers/gpu/drm/drm_probe_helper.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
> index 6fd08e04b323..081a849104f2 100644
> --- a/drivers/gpu/drm/drm_probe_helper.c
> +++ b/drivers/gpu/drm/drm_probe_helper.c
> @@ -780,7 +780,8 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
>  			      connector->name,
>  			      drm_get_connector_status_name(old_status),
>  			      drm_get_connector_status_name(connector->status));
> -		if (old_status != connector->status)
> +		if (old_status != connector->status ||
> +		    connector->status == connector_status_connected)
>  			changed = true;
>  	}
>  	drm_connector_list_iter_end(&conn_iter);
> -- 
> 2.21.0
>
Gwan-gyeong Mun April 18, 2019, 1:15 p.m. UTC | #2
On Thu, 2019-04-18 at 10:28 +0200, Daniel Vetter wrote:
> On Thu, Apr 18, 2019 at 11:09:29AM +0300, Gwan-gyeong Mun wrote:
> > The hotplug detection routine of drm_helper_hpd_irq_event() can
> > detect
> > changing of status of connector, but it can not detect changing of
> > properties of the connector.
> > e.g. changing of edid while suspend/resume, changing of dp lanes in
> > dp aux.
> > 
> > Following scenario explains one of them; A detection of changing of
> > edid.
> > 
> >  1) plug display device to a connector
> >  2) system suspend
> >  3) unplug 1)'s display device and plug the other display device to
> > a
> >     connector
> >  4) system resume
> > 
> > To solve explained cases, It fires off KMS hotplug events if
> > drm_helper_probe_detect() says the connector is connected.
> > 
> > Testcase: igt/kms_chamelium/hdmi-edid-change-during-hibernate
> > Testcase: igt/kms_chamelium/hdmi-edid-change-during-suspend
> > Testcase: igt/kms_chamelium/dp-edid-change-during-hibernate
> > Testcase: igt/kms_chamelium/dp-edid-change-during-suspend
> > 
> > Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> This isn't at all what I suggested.
> -Daniel
Because the code modification was followed by your comments, so I added
suggested-by line. I will remove this line and will resend it.
Br,
G.G.
> 
> > Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> > Link: 
> > https://lists.freedesktop.org/archives/dri-devel/2019-April/214572.html
> > ---
> >  drivers/gpu/drm/drm_probe_helper.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/drm_probe_helper.c
> > b/drivers/gpu/drm/drm_probe_helper.c
> > index 6fd08e04b323..081a849104f2 100644
> > --- a/drivers/gpu/drm/drm_probe_helper.c
> > +++ b/drivers/gpu/drm/drm_probe_helper.c
> > @@ -780,7 +780,8 @@ bool drm_helper_hpd_irq_event(struct drm_device
> > *dev)
> >  			      connector->name,
> >  			      drm_get_connector_status_name(old_status)
> > ,
> >  			      drm_get_connector_status_name(connector-
> > >status));
> > -		if (old_status != connector->status)
> > +		if (old_status != connector->status ||
> > +		    connector->status == connector_status_connected)
> >  			changed = true;
> >  	}
> >  	drm_connector_list_iter_end(&conn_iter);
> > -- 
> > 2.21.0
> >
Daniel Vetter April 23, 2019, 7:32 a.m. UTC | #3
On Thu, Apr 18, 2019 at 01:15:17PM +0000, Mun, Gwan-gyeong wrote:
> On Thu, 2019-04-18 at 10:28 +0200, Daniel Vetter wrote:
> > On Thu, Apr 18, 2019 at 11:09:29AM +0300, Gwan-gyeong Mun wrote:
> > > The hotplug detection routine of drm_helper_hpd_irq_event() can
> > > detect
> > > changing of status of connector, but it can not detect changing of
> > > properties of the connector.
> > > e.g. changing of edid while suspend/resume, changing of dp lanes in
> > > dp aux.
> > > 
> > > Following scenario explains one of them; A detection of changing of
> > > edid.
> > > 
> > >  1) plug display device to a connector
> > >  2) system suspend
> > >  3) unplug 1)'s display device and plug the other display device to
> > > a
> > >     connector
> > >  4) system resume
> > > 
> > > To solve explained cases, It fires off KMS hotplug events if
> > > drm_helper_probe_detect() says the connector is connected.
> > > 
> > > Testcase: igt/kms_chamelium/hdmi-edid-change-during-hibernate
> > > Testcase: igt/kms_chamelium/hdmi-edid-change-during-suspend
> > > Testcase: igt/kms_chamelium/dp-edid-change-during-hibernate
> > > Testcase: igt/kms_chamelium/dp-edid-change-during-suspend
> > > 
> > > Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > 
> > This isn't at all what I suggested.
> > -Daniel
> Because the code modification was followed by your comments, so I added
> suggested-by line. I will remove this line and will resend it.

Apologies for not being clear: I don't think this here is what we want
really, and it's not what I suggested. I'm not exactly sure why you think
this will work, essentially it just always generates a hotplug uevent for
irq, but totally ignores polling. I guess it works, but that's a hack, not
something we should merge.
-Daniel

> Br,
> G.G.
> > 
> > > Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> > > Link: 
> > > https://lists.freedesktop.org/archives/dri-devel/2019-April/214572.html
> > > ---
> > >  drivers/gpu/drm/drm_probe_helper.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/gpu/drm/drm_probe_helper.c
> > > b/drivers/gpu/drm/drm_probe_helper.c
> > > index 6fd08e04b323..081a849104f2 100644
> > > --- a/drivers/gpu/drm/drm_probe_helper.c
> > > +++ b/drivers/gpu/drm/drm_probe_helper.c
> > > @@ -780,7 +780,8 @@ bool drm_helper_hpd_irq_event(struct drm_device
> > > *dev)
> > >  			      connector->name,
> > >  			      drm_get_connector_status_name(old_status)
> > > ,
> > >  			      drm_get_connector_status_name(connector-
> > > >status));
> > > -		if (old_status != connector->status)
> > > +		if (old_status != connector->status ||
> > > +		    connector->status == connector_status_connected)
> > >  			changed = true;
> > >  	}
> > >  	drm_connector_list_iter_end(&conn_iter);
> > > -- 
> > > 2.21.0
> > >
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 6fd08e04b323..081a849104f2 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -780,7 +780,8 @@  bool drm_helper_hpd_irq_event(struct drm_device *dev)
 			      connector->name,
 			      drm_get_connector_status_name(old_status),
 			      drm_get_connector_status_name(connector->status));
-		if (old_status != connector->status)
+		if (old_status != connector->status ||
+		    connector->status == connector_status_connected)
 			changed = true;
 	}
 	drm_connector_list_iter_end(&conn_iter);