[alsa-devel] [PATCH 4/4] ALSA: hda - Wake the codec up on pin/ELD notify events

[David Henningsson]

On 2015-08-20 11:28, Takashi Iwai wrote:
> On Wed, 19 Aug 2015 10:48:58 +0200,
> David Henningsson wrote:
>>
>> Whenever there is an event from the i915 driver, wake the codec
>> and recheck plug/unplug + ELD status.
>>
>> This fixes the issue with lost unsol events in power save mode,
>> the codec and controller can now sleep in D3 and still know when
>> the HDMI monitor has been connected.
>>
>> Signed-off-by: David Henningsson <david.henningsson at canonical.com>
>
> This addition looks fine, but then we'll get double notification for
> the normal hotplug/unplug, one via component ops and another via unsol
> event?

Right, in case the unsol event actually works...

I would argue that the normal case would be that the controller and 
codec is in D3 which means that the unsol event never gets through - due 
to hw limitations - which is what triggered this patch set in the first 
place.

But yes, in some case we might get double notification, but this should 
not cause any trouble in practice. The unsol event could be turned off, 
but would it be okay to save that for a later patch set (so I don't miss 
the upcoming merge window)?

>
>
> thanks,
>
> Takashi
>
>> ---
>>   sound/pci/hda/patch_hdmi.c | 22 +++++++++++++++++++++-
>>   1 file changed, 21 insertions(+), 1 deletion(-)
>>
>> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
>> index a97db5f..932292c 100644
>> --- a/sound/pci/hda/patch_hdmi.c
>> +++ b/sound/pci/hda/patch_hdmi.c
>> @@ -37,6 +37,8 @@
>>   #include <sound/jack.h>
>>   #include <sound/asoundef.h>
>>   #include <sound/tlv.h>
>> +#include <sound/hdaudio.h>
>> +#include <sound/hda_i915.h>
>>   #include "hda_codec.h"
>>   #include "hda_local.h"
>>   #include "hda_jack.h"
>> @@ -144,6 +146,9 @@ struct hdmi_spec {
>>   	 */
>>   	struct hda_multi_out multiout;
>>   	struct hda_pcm_stream pcm_playback;
>> +
>> +	/* i915/powerwell (Haswell+/Valleyview+) specific */
>> +	struct i915_audio_component_audio_ops i915_audio_ops;
>>   };
>>
>>
>> @@ -2191,6 +2196,9 @@ static void generic_hdmi_free(struct hda_codec *codec)
>>   	struct hdmi_spec *spec = codec->spec;
>>   	int pin_idx;
>>
>> +	if (is_haswell_plus(codec) || is_valleyview_plus(codec))
>> +		snd_hdac_i915_register_notifier(NULL);
>> +
>>   	for (pin_idx = 0; pin_idx < spec->num_pins; pin_idx++) {
>>   		struct hdmi_spec_per_pin *per_pin = get_pin(spec, pin_idx);
>>
>> @@ -2316,6 +2324,14 @@ static void haswell_set_power_state(struct hda_codec *codec, hda_nid_t fg,
>>   	snd_hda_codec_set_power_to_all(codec, fg, power_state);
>>   }
>>
>> +static void intel_pin_eld_notify(void *audio_ptr, int port, int port_mst_index)
>> +{
>> +	struct hda_codec *codec = audio_ptr;
>> +	int pin_nid = port + 0x04;
>> +
>> +	check_presence_and_report(codec, pin_nid);
>> +}
>> +
>>   static int patch_generic_hdmi(struct hda_codec *codec)
>>   {
>>   	struct hdmi_spec *spec;
>> @@ -2342,8 +2358,12 @@ static int patch_generic_hdmi(struct hda_codec *codec)
>>   	if (is_valleyview_plus(codec) || is_skylake(codec))
>>   		codec->core.link_power_control = 1;
>>
>> -	if (is_haswell_plus(codec) || is_valleyview_plus(codec))
>> +	if (is_haswell_plus(codec) || is_valleyview_plus(codec)) {
>>   		codec->depop_delay = 0;
>> +		spec->i915_audio_ops.audio_ptr = codec;
>> +		spec->i915_audio_ops.pin_eld_notify = intel_pin_eld_notify;
>> +		snd_hdac_i915_register_notifier(&spec->i915_audio_ops);
>> +	}
>>
>>   	if (hdmi_parse_codec(codec) < 0) {
>>   		codec->spec = NULL;
>> --
>> 1.9.1
>>
>

-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic