[Intel-gfx] [PATCH i-g-t 1/5] lib/igt_chamelium: Add support for HPD toggle scheduling

[Lyude Paul]

This all looks great! I'm happy to see us finally getting rid of the
very hacky workaround I had to make async hotplugging work (to be fair,
it was only partly broken ;). Thanks for dealing with chameleond
upstream too, I couldn't stand how ugly the code in that thing is...

Anyway, this whole patchset looks good. The only thing I ask is that
you condense the patches a bit, mainly:

1-3 can all be one patch for adding real async HPD
4-5 can be another single patch for enabling VGA tests

On Mon, 2017-06-26 at 10:22 +0300, Paul Kocialkowski wrote:
> This adds support for the newly-introduced ScheduleHpdToggle XMLRPC
> method of the Chamelium's interface. It allows scheduling an HPD
> toggle,
> for which the call will return immediately.
> 
> This is especially useful for testing HPD during suspend/resume.
> 
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski at linux.intel.com>
> ---
>  lib/igt_chamelium.c | 22 ++++++++++++++++++++++
>  lib/igt_chamelium.h |  3 +++
>  2 files changed, 25 insertions(+)
> 
> diff --git a/lib/igt_chamelium.c b/lib/igt_chamelium.c
> index 4a2af796..523cc853 100644
> --- a/lib/igt_chamelium.c
> +++ b/lib/igt_chamelium.c
> @@ -447,6 +447,28 @@ void chamelium_fire_mixed_hpd_pulses(struct
> chamelium *chamelium,
>  	xmlrpc_DECREF(pulse_widths);
>  }
>  
> +/**
> + * chamelium_schedule_hpd_toggle:
> + * @chamelium: The Chamelium instance to use
> + * @port: The port to fire the HPD pulses on
> + * @delay_ms: Delay in milli-second before the toggle takes place
> + * @rising_edge: Whether the toggle should be a rising edge or a
> falling edge
> + *
> + * Instructs the chamelium to schedule an hpd toggle (either a
> rising edge or
> + * a falling edge, depending on @rising_edg) after @delay_ms have
> passed.
> + * This is useful for testing things such as hpd after a
> suspend/resume cycle.
> + */
> +void chamelium_schedule_hpd_toggle(struct chamelium *chamelium,
> +				   struct chamelium_port *port, int
> delay_ms,
> +				   bool rising_edge)
> +{
> +	igt_debug("Scheduling HPD toggle on %s in %d ms\n", port-
> >name,
> +		  delay_ms);
> +
> +	xmlrpc_DECREF(chamelium_rpc(chamelium, NULL,
> "ScheduleHpdToggle",
> +				    "(iii)", port->id, delay_ms,
> rising_edge));
> +}
> +
>  static void async_rpc_handler(const char *server_url, const char
> *method_name,
>  			      xmlrpc_value *param_array, void
> *user_data,
>  			      xmlrpc_env *fault, xmlrpc_value
> *result)
> diff --git a/lib/igt_chamelium.h b/lib/igt_chamelium.h
> index 15f60246..408a4b85 100644
> --- a/lib/igt_chamelium.h
> +++ b/lib/igt_chamelium.h
> @@ -61,6 +61,9 @@ void chamelium_fire_mixed_hpd_pulses(struct
> chamelium *chamelium,
>  void chamelium_fire_hpd_pulses(struct chamelium *chamelium,
>  			       struct chamelium_port *port,
>  			       int width_msec, int count);
> +void chamelium_schedule_hpd_toggle(struct chamelium *chamelium,
> +				   struct chamelium_port *port, int
> delay_ms,
> +				   bool rising_edge);
>  void chamelium_async_hpd_pulse_start(struct chamelium *chamelium,
>  				     struct chamelium_port *port,
>  				     bool high, int delay_secs);