[igt-dev] [Patch][i-g-t 1/2] lib/igt_kms: Add support for detecting connector events

[Ramalingam C]

On 2020-06-16 at 16:28:11 +0530, Ankit Nautiyal wrote:
> Currently, the event_detect function checks the property val for
> "HOTPLUG" and "LEASE" both of which are set to '1' when these events
> are sent.
> 
> This cannot be used for detecting connector events such as HDCP event
> as connector events are sent along with property to signify which
> property of which connector has changed. Connector ID and property id
> are provided along with "CONNECTOR" and "PROPERTY" as udev
> property-value pairs. Eg. for HDCP, the connector id of the connector
> whose hdcp status changed, and the property id of the
> ‘CONTENT_PROTECTION’ property are sent with uevent.
> 
> This patch modifies the event_detect function to check multiple
> properties with different expected values. It also adds support to
> detect connector event for a given pair of connector and property ids.
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> ---
>  lib/igt_kms.c | 61 ++++++++++++++++++++++++++++++++++++++-------------
>  lib/igt_kms.h |  2 ++
>  2 files changed, 48 insertions(+), 15 deletions(-)
> 
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index 54de45e5..7177231e 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -4164,32 +4164,57 @@ struct udev_monitor *igt_watch_hotplug(void)
>  }
>  
>  static bool event_detected(struct udev_monitor *mon, int timeout_secs,
> -			   const char *property)
> +			   const char **property, int *expected_val, int num_props)
>  {
>  	struct udev_device *dev;
> -	const char *hotplug_val;
> +	const char *prop_val_str;
>  	struct pollfd fd = {
>  		.fd = udev_monitor_get_fd(mon),
>  		.events = POLLIN
>  	};
> -	bool hotplug_received = false;
> +	bool event_received = false;
> +	int i;
>  
> -	/* Go through all of the events pending on the udev monitor. Once we
> -	 * receive a hotplug, we continue going through the rest of the events
> -	 * so that redundant hotplug events don't change the results of future
> -	 * checks
> +	/* Go through all of the events pending on the udev monitor.
> +	 * Match the given set of properties and their values to
> +	 * the expected values.
>  	 */
> -	while (!hotplug_received && poll(&fd, 1, timeout_secs * 1000)) {
> +	while (!event_received && poll(&fd, 1, timeout_secs * 1000)) {
>  		dev = udev_monitor_receive_device(mon);
> -
> -		hotplug_val = udev_device_get_property_value(dev, property);
> -		if (hotplug_val && atoi(hotplug_val) == 1)
> -			hotplug_received = true;
> +		for (i = 0; i < num_props; i++) {
> +			event_received = true;
Not needed.
> +			prop_val_str = udev_device_get_property_value(dev, property[i]);
> +			if (!prop_val_str || atoi(prop_val_str) != expected_val[i]) {
> +				event_received = false;
Not needed.
> +				break;
> +			}
> +		}
		if (i == num_props)
			event_received = true;
>  
>  		udev_device_unref(dev);
>  	}
>  
> -	return hotplug_received;
> +	return event_received;
> +}
> +
> +/**
> + * igt_conn_event_detected:
> + * @mon: A udev monitor initialized with #igt_watch_hotplug
> + * @conn_id: Connector id of the Connector for which the property change is
> + * expected.
> + * @prop_id: Property id for which the change is expected.
> + * @timeout_secs: How long to wait for a connector event to occur.
> + *
> + * Assert that a connector event is received for a given connector and property.
> + *
> + * Returns: true if the connector event was received, false if we timed out
> + */
> +bool igt_conn_event_detected(struct udev_monitor *mon, uint32_t conn_id,
> +			     uint32_t prop_id, int timeout_secs)
> +{
> +	const char *props[2] = {"CONNECTOR", "PROPERTY"};
> +	int expected_val[2] = {conn_id, prop_id};
> +
> +	return event_detected(mon, timeout_secs, props, expected_val, 2);
>  }
>  
>  /**
> @@ -4203,7 +4228,10 @@ static bool event_detected(struct udev_monitor *mon, int timeout_secs,
>   */
>  bool igt_hotplug_detected(struct udev_monitor *mon, int timeout_secs)
>  {
> -	return event_detected(mon, timeout_secs, "HOTPLUG");
> +	const char *props[1] = {"HOTPLUG"};
> +	int expected_val = 1;
> +
> +	return event_detected(mon, timeout_secs, props, &expected_val, 1);
>  }
>  
>  /**
> @@ -4217,7 +4245,10 @@ bool igt_hotplug_detected(struct udev_monitor *mon, int timeout_secs)
>   */
>  bool igt_lease_change_detected(struct udev_monitor *mon, int timeout_secs)
>  {
> -	return event_detected(mon, timeout_secs, "LEASE");
> +	const char *props[1] = {"LEASE"};
> +	int expected_val = 1;
> +
> +	return event_detected(mon, timeout_secs, props, &expected_val, 1);
>  }
>  
>  /**
> diff --git a/lib/igt_kms.h b/lib/igt_kms.h
> index cd3fdbc0..27f1f729 100644
> --- a/lib/igt_kms.h
> +++ b/lib/igt_kms.h
> @@ -777,6 +777,8 @@ bool igt_hotplug_detected(struct udev_monitor *mon,
>  			  int timeout_secs);
>  bool igt_lease_change_detected(struct udev_monitor *mon,
>  			       int timeout_secs);
> +bool igt_conn_event_detected(struct udev_monitor *mon, uint32_t conn_id,
> +			     uint32_t prop_id, int timeout_msecs);
>  void igt_flush_hotplugs(struct udev_monitor *mon);
We need to have generich flush too like igt_(watch/flush/cleanup)_udev_event()

-Ram
>  void igt_cleanup_hotplug(struct udev_monitor *mon);
>  
> -- 
> 2.17.1
>