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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52A51C4332F for ; Fri, 12 Nov 2021 14:19:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3C64D610E6 for ; Fri, 12 Nov 2021 14:19:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235274AbhKLOWO (ORCPT ); Fri, 12 Nov 2021 09:22:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235242AbhKLOWN (ORCPT ); Fri, 12 Nov 2021 09:22:13 -0500 Received: from relay03.th.seeweb.it (relay03.th.seeweb.it [IPv6:2001:4b7a:2000:18::164]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86AC5C061767 for ; Fri, 12 Nov 2021 06:19:22 -0800 (PST) Received: from SoMainline.org (94-209-165-62.cable.dynamic.v4.ziggo.nl [94.209.165.62]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by m-r1.th.seeweb.it (Postfix) with ESMTPSA id CD8CB1F633; Fri, 12 Nov 2021 15:19:18 +0100 (CET) Date: Fri, 12 Nov 2021 15:19:17 +0100 From: Marijn Suijten To: Daniel Thompson Cc: phone-devel@vger.kernel.org, Andy Gross , Bjorn Andersson , Rob Herring , Lee Jones , Jingoo Han , ~postmarketos/upstreaming@lists.sr.ht, AngeloGioacchino Del Regno , Konrad Dybcio , Martin Botka , Jami Kettunen , Pavel Dubrova , Kiran Gunda , Bryan Wu , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org Subject: Re: [RESEND PATCH v2 05/13] backlight: qcom-wled: Override default length with qcom,enabled-strings Message-ID: <20211112141917.akufukmeyz5enjg3@SoMainline.org> Mail-Followup-To: Marijn Suijten , Daniel Thompson , phone-devel@vger.kernel.org, Andy Gross , Bjorn Andersson , Rob Herring , Lee Jones , Jingoo Han , ~postmarketos/upstreaming@lists.sr.ht, AngeloGioacchino Del Regno , Konrad Dybcio , Martin Botka , Jami Kettunen , Pavel Dubrova , Kiran Gunda , Bryan Wu , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org References: <20211112002706.453289-1-marijn.suijten@somainline.org> <20211112002706.453289-6-marijn.suijten@somainline.org> <20211112121238.kb3kkt6xzv5so26j@maple.lan> <20211112124522.g7e3m7l2oxxxobof@SoMainline.org> <20211112132336.z2x4bzrfqr4u3jol@maple.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211112132336.z2x4bzrfqr4u3jol@maple.lan> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-11-12 13:23:36, Daniel Thompson wrote: > On Fri, Nov 12, 2021 at 01:45:22PM +0100, Marijn Suijten wrote: > > On 2021-11-12 12:12:38, Daniel Thompson wrote: > > > On Fri, Nov 12, 2021 at 01:26:58AM +0100, Marijn Suijten wrote: > > > > The length of qcom,enabled-strings as property array is enough to > > > > determine the number of strings to be enabled, without needing to set > > > > qcom,num-strings to override the default number of strings when less > > > > than the default (which is also the maxium) is provided in DT. > > > > > > > > Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3") > > > > Signed-off-by: Marijn Suijten > > > > Reviewed-by: AngeloGioacchino Del Regno > > > > --- > > > > drivers/video/backlight/qcom-wled.c | 2 ++ > > > > 1 file changed, 2 insertions(+) > > > > > > > > diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c > > > > index c5232478a343..9bfbf601762a 100644 > > > > --- a/drivers/video/backlight/qcom-wled.c > > > > +++ b/drivers/video/backlight/qcom-wled.c > > > > @@ -1518,6 +1518,8 @@ static int wled_configure(struct wled *wled) > > > > return -EINVAL; > > > > } > > > > } > > > > + > > > > + cfg->num_strings = string_len; > > > > > > I still don't really understand why this wants to be a separate patch. > > > > I'm viewing this as a separate issue, and this makes it easier to > > document the change in a loose commit. > > > > > The warning text emitted by the previous patch (whatever text we agree > > > on) will be nonsense until this patch is applied. > > > > > > If this patch cannot appear before the warning is introduces then there > > > is no correct order for patches 4 and 5 (which implies they should be the > > > same patch). > > > > Agreed, this is a weird way of doing things in v2 - the error message is > > printed yet the length of qcom,enabled-strings is always ignored before > > this patch. > > > > If we were to reorder patch 5 before patch 4 that should also > > temporarily move `cfg->num_strings = cfg->num_strings + 1;` right below > > this `if` so that `qcom,num-strings` remains the definitive way to > > set/override length. That's doable, and makes it easier to read patch 4 > > as that bit of code will be replaced by of_property_read_u32 on that > > exact line. Let me know which method you prefer. > > Personally I would just squash them together. There are no redundant > values in the DT that could be fixed until we can use the string_len > to set num_strings. Reordering this patch before patch 4 in the way described above should allow just that, except that no warnings will be given for ambiguity until patch 4 is applied after that - which is weird given that that patch only intends the off-by-one error. Perhaps we should keep the order as it is, but add the ambiguity warning in this patch instead. That means we have one patch to fix the off-by-one first, and another that allows qcom,num-strings to provide a default for num_strings. I guess that's better to keep separated? - Marijn