[igt-dev] [PATCH i-g-t v2] tests/kms_chamelium: Make sure we wait for each connectors' hotplug event

[Paul Kocialkowski]

On Wed, 2019-05-08 at 11:24 +0300, Imre Deak wrote:
> After scheduling an HPD toggle event, make sure that we wait for the
> hotplug event for each connector that may be sent by the driver.
> 
> Depending on the scheduling there could be 1 event or as many events as
> connectors we scheduled an HPD toggle event on, depending on the timing.
> So if we don't yet see the expected connector state on a given connector
> try to wait for an additional hotplug event and reprobe/recheck the
> state.

This changes makes good sense to me, so:

Reviewed-By: Paul Kocialkowski <paul.kocialkowski at bootlin.com>

And it brings back hard feelings about the hotplug interface we have
today...

Cheers,

Paul

> v2:
> - s/igt_assert(x >= y)/igt_assert_lte(y, x)/ to see the actual limits in
>   the debugging output. (Lyude)
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110534
> Cc: Paul Kocialkowski <paul.kocialkowski at bootlin.com>
> Cc: Lyude Paul <lyude at redhat.com>
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> Reviewed-by: Lyude Paul <lyude at redhat.com>
> ---
>  tests/kms_chamelium.c | 45 +++++++++++++++++++++++++++++++++++++------
>  1 file changed, 39 insertions(+), 6 deletions(-)
> 
> diff --git a/tests/kms_chamelium.c b/tests/kms_chamelium.c
> index 714e5e06..502f1efa 100644
> --- a/tests/kms_chamelium.c
> +++ b/tests/kms_chamelium.c
> @@ -284,11 +284,32 @@ test_edid_read(data_t *data, struct chamelium_port *port,
>  	drmModeFreeConnector(connector);
>  }
>  
> +/* Wait for hotplug and return the remaining time left from timeout */
> +static bool wait_for_hotplug(struct udev_monitor *mon, int *timeout)
> +{
> +	struct timespec start, end;
> +	int elapsed;
> +	bool detected;
> +
> +	igt_assert_eq(igt_gettime(&start), 0);
> +	detected = igt_hotplug_detected(mon, *timeout);
> +	igt_assert_eq(igt_gettime(&end), 0);
> +
> +	elapsed = igt_time_elapsed(&start, &end);
> +	igt_assert_lte(0, elapsed);
> +	*timeout = max(0, *timeout - elapsed);
> +
> +	return detected;
> +}
> +
>  static void
>  try_suspend_resume_hpd(data_t *data, struct chamelium_port *port,
>  		       enum igt_suspend_state state, enum igt_suspend_test test,
>  		       struct udev_monitor *mon, bool connected)
>  {
> +	drmModeConnection target_state = connected ? DRM_MODE_DISCONNECTED :
> +						     DRM_MODE_CONNECTED;
> +	int timeout = HOTPLUG_TIMEOUT;
>  	int delay;
>  	int p;
>  
> @@ -310,17 +331,29 @@ try_suspend_resume_hpd(data_t *data, struct chamelium_port *port,
>  	}
>  
>  	igt_system_suspend_autoresume(state, test);
> +	igt_assert(wait_for_hotplug(mon, &timeout));
>  
> -	igt_assert(igt_hotplug_detected(mon, HOTPLUG_TIMEOUT));
>  	if (port) {
> -		igt_assert_eq(reprobe_connector(data, port), connected ?
> -			      DRM_MODE_DISCONNECTED : DRM_MODE_CONNECTED);
> +		igt_assert_eq(reprobe_connector(data, port), target_state);
>  	} else {
>  		for (p = 0; p < data->port_count; p++) {
> +			drmModeConnection current_state;
> +
>  			port = data->ports[p];
> -			igt_assert_eq(reprobe_connector(data, port), connected ?
> -				      DRM_MODE_DISCONNECTED :
> -				      DRM_MODE_CONNECTED);
> +			/*
> +			 * There could be as many hotplug events sent by
> +			 * driver as connectors we scheduled an HPD toggle on
> +			 * above, depending on timing. So if we're not seeing
> +			 * the expected connector state try to wait for an HPD
> +			 * event for each connector/port.
> +			 */
> +			current_state = reprobe_connector(data, port);
> +			if (p > 0 && current_state != target_state) {
> +				igt_assert(wait_for_hotplug(mon, &timeout));
> +				current_state = reprobe_connector(data, port);
> +			}
> +
> +			igt_assert_eq(current_state, target_state);
>  		}
>  
>  		port = NULL;
-- 
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com