At Mon, 21 Nov 2011 14:48:11 +0800, Wu Fengguang wrote:
On Wed, Nov 16, 2011 at 04:29:47PM +0800, Wu, Fengguang wrote:
The Intel HDMI chips (ironlake at least) are found to have ~250ms delay between the ELD_Valid=1 hotplug event is send and the ELD buffer becomes actually readable. During the time the ELD buffer is mysteriously all 0.
Fix it by scheduling a delayed work to re-read ELD buffer after 300ms.
Just FYI.
Up to now the 300ms looks sufficient. But if ever there comes longer delays, I've already prepared a patch for retrying it for several times ;)
Thanks. I think it's safer to have a repoll mechanism. But, looking at the patch, one question remains:
@@ -989,10 +990,9 @@ static void hdmi_present_sense(struct hd if (eld_valid) { if (!snd_hdmi_get_eld(eld, codec, pin_nid)) snd_hdmi_show_eld(eld);
else if (retry) {
else if (repoll) { queue_delayed_work(codec->bus->workq,
&per_pin->work,msecs_to_jiffies(300));
&per_pin->work, repoll * HZ / 3);
Do you really want to wait longer with a higher repoll number?
Takashi