From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomi Valkeinen Subject: Re: [PATCH 3/3] OMAPDSS: HDMI: Cache EDID Date: Thu, 28 Jun 2012 16:31:18 +0300 Message-ID: <1340890278.5037.91.camel@deskari> References: <1340805944-28805-1-git-send-email-jaswinder.singh@linaro.org> <1340869729.5037.7.camel@deskari> <1340878461.5037.30.camel@deskari> <1340881815.5037.53.camel@deskari> <4FEC47FA.1040801@linaro.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-j8zU8B36FDxU2Ay1eBg3" Return-path: Received: from na3sys009aog124.obsmtp.com ([74.125.149.151]:46717 "EHLO na3sys009aog124.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751652Ab2F1NbX (ORCPT ); Thu, 28 Jun 2012 09:31:23 -0400 Received: by bkty8 with SMTP id y8so2158676bkt.31 for ; Thu, 28 Jun 2012 06:31:20 -0700 (PDT) In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Jassi Brar Cc: Andy Green , mythripk@ti.com, linux-omap@vger.kernel.org, linux-fbdev@vger.kernel.org, n-dechesne@ti.com, patches@linaro.org --=-j8zU8B36FDxU2Ay1eBg3 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, 2012-06-28 at 18:43 +0530, Jassi Brar wrote: > On 28 June 2012 17:33, Andy Green wrote: > > If Jassi's alright with it we might have a go at implementing this, but= can > > you define a bit more about how we logically tell DSS that we want to, = eg, > > disable HDMI totally? > > > A quick reaction of my guts say, we simply enable 5V/HPD_IRQ during > probe and disable during remove. The problem with this is a feature of omapdss: we can have multiple displays for the same output, of which only one can be enabled at the same time. What this means is that you shouldn't (and in some cases can't) allocate or enable resources in probe that may be shared, because then the driver for both displays would try to allocate the same resource. Sure, this is not a problem for the HDMI configuration we are using now, but it's still against the panel model we have. Thus we should allocate resources only when the panel device is turned on, and release them when it's disabled. I do think the model is slightly broken, but that's what we have now. And I'm also not even sure how it should be fixed... And also, as I said earlier, if you keep it enabled all the time, it'll eat power even if the user is never going to use HDMI. On a desktop I guess the power consumption wouldn't be an issue, but I do feel a bit uneasy about it on an embedded device. > HDMI enable/disable via /sysfs/ and HPD (de)assertion, switch only > HDMI_PHY on/off. > The user selecting "Autodetect and Configure" option would then equate > to "(un)loading" of the HDMI driver. HDMI cannot be currently compiled as a separate module. Although I think you can detach a device and a driver, achieving the same. Is that what you meant with unloading? Tomi --=-j8zU8B36FDxU2Ay1eBg3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJP7FymAAoJEPo9qoy8lh7123kP/162EklV443bgG4K1LM/R3XM cKr+sBr3aNM2TefYBONvlnvGnmkERtvgx31mexl13+bAZUYunnCMud//6PY4VNFn a30a9NAozgoxG33TGOHLEi2wWUiExY8xYXknaYCWq+cr2eQFrgwO8QlDZS/L9ACa DTrUEQK7G5mGcrAYZAYAxchJP21gP/iliBDyOktVY57TcVgcwbbhFf+MNyfKx24J tGwTNNqYOta8XZ63BntOKVNNK8vjzD+LEILpDxmmg8iRi1w6E03oi6QsQow3JRDg e60j/j/tolX13NMqGPzsUI2jrahrxyTHQjOyVXf341We0O7AkamiNvAW+MWJvDz1 RcS/1cBoN7xgDj5BmliP+/NA/dGBlrfkpVrWxbau4rqP2RXjotZ0/ZHCM1QB0Go+ 7cKkkwLIRXycWK61jG/kpap+RwqXo/rKsGqIt5pn1EpiX/q/4rXNk0TBvOXna6uv 6cFhcuSGYRO0fw6H0GGDY8uNNwqFlWdoblmVp0dpCa7Q3fQlnonWHEFjbbjHZLBA c2fL21YmON5qVB3GQ9ZmWPfIR6+sjAk3l3nI69S47LJM96LXwv940di3modvze7V ZkavqZgOJ4xBfP2uVJ5HXW8+SRdYl+roB1sQfIH06jbYXiTQ2a9FdgeaeAkdmFWK 8cV++HD8CJHCs4L/ftYc =ZP1C -----END PGP SIGNATURE----- --=-j8zU8B36FDxU2Ay1eBg3--