From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754886AbdBGPes (ORCPT ); Tue, 7 Feb 2017 10:34:48 -0500 Received: from mail.free-electrons.com ([62.4.15.54]:48847 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754525AbdBGPeq (ORCPT ); Tue, 7 Feb 2017 10:34:46 -0500 Date: Tue, 7 Feb 2017 16:34:44 +0100 From: Maxime Ripard To: Noralf =?iso-8859-1?Q?Tr=F8nnes?= Cc: Rob Herring , Mark Rutland , Thierry Reding , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH 0/2] drm/panel: Add support for the Sitronix ST7789V Message-ID: <20170207153444.yc7znfkje7hm4em6@lukather> References: <2db19e6e-9857-1c92-dc77-c6b862cc771f@tronnes.org> <20170206103938.3yghvugiwpzkij6r@lukather> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="weq2r653steeqr54" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --weq2r653steeqr54 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Feb 06, 2017 at 12:29:31PM +0100, Noralf Tr=F8nnes wrote: >=20 > Den 06.02.2017 11.39, skrev Maxime Ripard: > > Hi Noralf, > >=20 > > On Fri, Feb 03, 2017 at 07:48:51PM +0100, Noralf Tr=F8nnes wrote: > > > Den 03.02.2017 10.59, skrev Maxime Ripard: > > > > Hi, > > > >=20 > > > > Here is an attempt at supporting the ST7789V LCD controller from Si= tronix. > > > What happens if there's another panel driven by ST7789V that needs > > > a different controller initialization? > > You know those panels / controllers much better than I do, but why > > would that be the case? > >=20 > > > Maybe it's better to name it after the panel, not the controller. > > I guess you could also use that panel directly without the controller? >=20 > A controller can drive many different panels that can require different > initializations. I faced that with staging/fbtft, when I wrote > controller drivers having initialization code, and then came across > displays with the same controller but with a different initialization. >=20 > Trying to write controller drivers for these controllers is very > difficult with all the possible permutations. On top of that we have > those undocumented commands/registers. >=20 > Some panels come with embedded controllers, in which case it makes > sense to write a driver for the panel. >=20 > But if the panel and controller are separate, then I don't know. Maybe > the chance of coming across two uncompatible ST7789V and panel > combinations in drm/panel is extremly low. Hmm, I see. If we ever come across that case, I guess we could just add new optional properties to override the current sequence. Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com --weq2r653steeqr54 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIcBAEBCAAGBQJYmekPAAoJEBx+YmzsjxAgwcoQALhFnTQ5JPZhF8o1onXRvZLq K9dn0OhbjzOx0ZeKcz3UpJ4SXA+rr8gJ7fcQAqdtyw6uagVZMObDVV6HGJZqTImz Em3RXvI90tZaIxpFsEf3BBW1eymyJlNoy93DINVDVJ9H58zGUJDLOYLVVibsSkBf Pcl+4SVDTEN/httdl8mVNS2XJaGNKB35mLX8UUIs76g1HRnobZx9mnEsZhayNtZa 12eef01liSwXUwAyldiI1n4ppOAVhrCNxDtvpL3L7/ka0cisblxqnxZnW2REG3xu dAP6KVHBKzXrwWNRRjX4spmS+fJC1T8IJnvhrAAqabHFoChxFe7vvl/x8qAkVxY9 EaSVhTiPQGo67oIyedHsh5TvoaIFhXqGIJiQc92kKkaoLA7GEe02UF9QVVgN4Ogu GGb3C1wQbqhTdZrdKNYKJOhJQml66W7gzX/ByO3os35cQNiNr9fqLdw0JJ2d7UTa MI0pJNXVrnBRZpS5Bg1L8SohUss4FZSY5ld0tZMpRDT+3s1qyGCu3yr7F5g+Yy5K 27sPEz9+NJIhjZCDQMJIcBsGsu3+XzlST9P9fuDXPdKgkB1QzRkRLmQg04seWLOD IeHZqzCCESRSSmXy9f0QZlwbUIdK60TSWcI2vDm/+JdTSmNjpRBYhcx+DGK9OGLk lnCruFRhpJXKVW44Zf6P =vSGe -----END PGP SIGNATURE----- --weq2r653steeqr54--