From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DDC27C2BB85 for ; Tue, 14 Apr 2020 21:11:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B8FDF2074D for ; Tue, 14 Apr 2020 21:11:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=pp3345.net header.i=@pp3345.net header.b="kADJdAdB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391672AbgDNVLc (ORCPT ); Tue, 14 Apr 2020 17:11:32 -0400 Received: from saul.pp3345.net ([163.172.111.124]:38578 "EHLO saul.pp3345.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733025AbgDNVLX (ORCPT ); Tue, 14 Apr 2020 17:11:23 -0400 Received: from localhost (localhost [127.0.0.1]) (Authenticated sender: dev@pp3345.net) by saul.pp3345.net (Postcow) with ESMTPSA id 3BA379A460D; Tue, 14 Apr 2020 23:11:10 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pp3345.net; s=saul; t=1586898672; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:openpgp:autocrypt; bh=dlSDoutPT33xOVXUFaJb/6vXllGM0ISsKTqsxM9cpT0=; b=kADJdAdBnCzNpbP1Tk5AcFKwIID3OpRRqCYqSr5KRV02Z/J8YwOdGwiqiUg2Z9hTaqTori bibno0ZXercCDBJWOihH4wZ9VaTkyJFpWpldGzonYitnC0w1+MlGmrz2Dfbhkv3NGo4jmY GGMMOVeYGfd0KgV/xBAxuU/QsA23D2cUS3c924BCNOTsiVl4PHU4nHcJ6u9c/0445RatH2 fIprRdmhfk6+M+TjKjKkh0xBX8HRf4OR5lUhXPLTZUn6GtokvU93sdAKSTXJPiprBS1w0R LmgF0hnW5Ulf69YYSOlbK0qN+UTsp2ekLl0T9nisyhNBao7ULVqvCN4IX1hjIg== Message-ID: <2cfe44c96818515939050ad19e9c248e50519be2.camel@pp3345.net> Subject: Re: [PATCH 5/5] drm/i915: Replace "Broadcast RGB" with "RGB quantization range" property From: Yussuf Khalil To: Daniel Vetter , Jani Nikula Cc: Simon Ser , David Airlie , "dri-devel@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" , Thomas Zimmermann Date: Tue, 14 Apr 2020 23:11:07 +0200 In-Reply-To: <20200414123404.GT3456981@phenom.ffwll.local> References: <20200413214024.46500-1-dev@pp3345.net> <20200413214024.46500-6-dev@pp3345.net> <87ftd6mi3e.fsf@intel.com> <87d08amhy5.fsf@intel.com> <20200414123404.GT3456981@phenom.ffwll.local> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.1 (3.36.1-1.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2020-04-14 at 14:34 +0200, Daniel Vetter wrote: > On Tue, Apr 14, 2020 at 02:21:06PM +0300, Jani Nikula wrote: > > On Tue, 14 Apr 2020, Jani Nikula > > wrote: > > > On Mon, 13 Apr 2020, Simon Ser wrote: > > > > On Monday, April 13, 2020 11:40 PM, Yussuf Khalil < > > > > dev@pp3345.net> wrote: > > > > > > > > > DRM now has a globally available "RGB quantization range" > > > > > connector > > > > > property. i915's "Broadcast RGB" that fulfils the same > > > > > purpose is now > > > > > considered deprecated, so drop it in favor of the DRM > > > > > property. > > > > > > > > For a UAPI point-of-view, I'm not sure this is fine. Some user- > > > > space > > > > might depend on this property, dropping it would break such > > > > user-space. > > > > > > Agreed. > > > > > > > Can we make this property deprecated but still keep it for > > > > backwards > > > > compatibility? > > > > > > Would be nice to make the i915 specific property an "alias" for > > > the new > > > property, however I'm not sure how you'd make that happen. > > > Otherwise > > > juggling between the two properties is going to be a nightmare. > > > > Ah, the obvious easy choice is to use the property and enum names > > already being used by i915 and gma500, and you have no problem. > > Perhaps > > they're not the names you'd like, but then looking at the total > > lack of > > consistency across property naming makes them fit right in. ;) > > Yeah if we don't have contradictory usage across drivers when > modernizing > these properties, then let's just stick with the names already there. > It's > not pretty, but works better since more userspace/internet howtos > know how > to use this stuff. > -Daniel Note that i915's "Broadcast RGB" isn't the same as gma500's: i915 has an "Automatic" option, whereas gma500 does not. Also, radeon has a property called "output_csc" that fulfills a similar purpose. Looking at the code, though, it seems that radeon does not adhere to the standard correctly (or I am missing something). An alternative would be to leave the existing driver-specific properties and change them to be pseudo-aliases for the "RGB quantization range" property. This can be done by letting the drivers read from and write to the new property when user-space tries to read or modify the driver's property. This way we could retain full backwards compatibility for all drivers equally. What do you think? Regards Yussuf From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 89418C2BB1D for ; Tue, 14 Apr 2020 21:11:23 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4870F2074D for ; Tue, 14 Apr 2020 21:11:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=pp3345.net header.i=@pp3345.net header.b="kADJdAdB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4870F2074D Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=pp3345.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B5E8689B0D; Tue, 14 Apr 2020 21:11:22 +0000 (UTC) Received: from saul.pp3345.net (saul.pp3345.net [163.172.111.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 16CAD89449 for ; Tue, 14 Apr 2020 21:11:21 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) (Authenticated sender: dev@pp3345.net) by saul.pp3345.net (Postcow) with ESMTPSA id 3BA379A460D; Tue, 14 Apr 2020 23:11:10 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pp3345.net; s=saul; t=1586898672; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:openpgp:autocrypt; bh=dlSDoutPT33xOVXUFaJb/6vXllGM0ISsKTqsxM9cpT0=; b=kADJdAdBnCzNpbP1Tk5AcFKwIID3OpRRqCYqSr5KRV02Z/J8YwOdGwiqiUg2Z9hTaqTori bibno0ZXercCDBJWOihH4wZ9VaTkyJFpWpldGzonYitnC0w1+MlGmrz2Dfbhkv3NGo4jmY GGMMOVeYGfd0KgV/xBAxuU/QsA23D2cUS3c924BCNOTsiVl4PHU4nHcJ6u9c/0445RatH2 fIprRdmhfk6+M+TjKjKkh0xBX8HRf4OR5lUhXPLTZUn6GtokvU93sdAKSTXJPiprBS1w0R LmgF0hnW5Ulf69YYSOlbK0qN+UTsp2ekLl0T9nisyhNBao7ULVqvCN4IX1hjIg== Message-ID: <2cfe44c96818515939050ad19e9c248e50519be2.camel@pp3345.net> Subject: Re: [PATCH 5/5] drm/i915: Replace "Broadcast RGB" with "RGB quantization range" property From: Yussuf Khalil To: Daniel Vetter , Jani Nikula Date: Tue, 14 Apr 2020 23:11:07 +0200 In-Reply-To: <20200414123404.GT3456981@phenom.ffwll.local> References: <20200413214024.46500-1-dev@pp3345.net> <20200413214024.46500-6-dev@pp3345.net> <87ftd6mi3e.fsf@intel.com> <87d08amhy5.fsf@intel.com> <20200414123404.GT3456981@phenom.ffwll.local> User-Agent: Evolution 3.36.1 (3.36.1-1.fc32) MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Thomas Zimmermann Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, 2020-04-14 at 14:34 +0200, Daniel Vetter wrote: > On Tue, Apr 14, 2020 at 02:21:06PM +0300, Jani Nikula wrote: > > On Tue, 14 Apr 2020, Jani Nikula > > wrote: > > > On Mon, 13 Apr 2020, Simon Ser wrote: > > > > On Monday, April 13, 2020 11:40 PM, Yussuf Khalil < > > > > dev@pp3345.net> wrote: > > > > > > > > > DRM now has a globally available "RGB quantization range" > > > > > connector > > > > > property. i915's "Broadcast RGB" that fulfils the same > > > > > purpose is now > > > > > considered deprecated, so drop it in favor of the DRM > > > > > property. > > > > > > > > For a UAPI point-of-view, I'm not sure this is fine. Some user- > > > > space > > > > might depend on this property, dropping it would break such > > > > user-space. > > > > > > Agreed. > > > > > > > Can we make this property deprecated but still keep it for > > > > backwards > > > > compatibility? > > > > > > Would be nice to make the i915 specific property an "alias" for > > > the new > > > property, however I'm not sure how you'd make that happen. > > > Otherwise > > > juggling between the two properties is going to be a nightmare. > > > > Ah, the obvious easy choice is to use the property and enum names > > already being used by i915 and gma500, and you have no problem. > > Perhaps > > they're not the names you'd like, but then looking at the total > > lack of > > consistency across property naming makes them fit right in. ;) > > Yeah if we don't have contradictory usage across drivers when > modernizing > these properties, then let's just stick with the names already there. > It's > not pretty, but works better since more userspace/internet howtos > know how > to use this stuff. > -Daniel Note that i915's "Broadcast RGB" isn't the same as gma500's: i915 has an "Automatic" option, whereas gma500 does not. Also, radeon has a property called "output_csc" that fulfills a similar purpose. Looking at the code, though, it seems that radeon does not adhere to the standard correctly (or I am missing something). An alternative would be to leave the existing driver-specific properties and change them to be pseudo-aliases for the "RGB quantization range" property. This can be done by letting the drivers read from and write to the new property when user-space tries to read or modify the driver's property. This way we could retain full backwards compatibility for all drivers equally. What do you think? Regards Yussuf _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel