From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: Re: [PATCH v5 05/11] drm: add Atmel HLCDC Display Controller support Date: Tue, 23 Sep 2014 11:55:42 +0200 Message-ID: <5421439E.80501@atmel.com> References: <1410165822-16868-1-git-send-email-boris.brezillon@free-electrons.com> <1410165822-16868-6-git-send-email-boris.brezillon@free-electrons.com> <20140922211811.11279ff0@bbrezillon> <20140923063232.GG30514@ulmo> <20140923092436.12b1f2c4@bbrezillon> <20140923084228.GN30514@ulmo> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140923084228.GN30514@ulmo> Sender: linux-pwm-owner@vger.kernel.org To: Thierry Reding , Boris BREZILLON Cc: David Airlie , dri-devel@lists.freedesktop.org, Samuel Ortiz , Lee Jones , linux-pwm@vger.kernel.org, Jean-Christophe Plagniol-Villard , Alexandre Belloni , Andrew Victor , Laurent Pinchart , Bo Shen , Ludovic Desroches , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Hi Thierry, On 23/09/2014 10:42, Thierry Reding : > On Tue, Sep 23, 2014 at 09:24:36AM +0200, Boris BREZILLON wrote: >> Hi Thierry, >> >> On Tue, 23 Sep 2014 08:32:33 +0200 >> Thierry Reding wrote: >> >>> On Mon, Sep 22, 2014 at 09:18:11PM +0200, Boris BREZILLON wrote: >>>> On Mon, 8 Sep 2014 10:43:36 +0200 Boris BREZILLON wrote: >>> [...] >>>>> diff --git a/drivers/gpu/drm/atmel-hlcdc/Kconfig b/drivers/gpu/drm/atmel-hlcdc/Kconfig >>>>> new file mode 100644 >>>>> index 0000000..6d0d785 >>>>> --- /dev/null >>>>> +++ b/drivers/gpu/drm/atmel-hlcdc/Kconfig >>>>> @@ -0,0 +1,13 @@ >>>>> +config DRM_ATMEL_HLCDC >>>>> + tristate "DRM Support for ATMEL HLCDC Display Controller" >>>>> + depends on DRM && OF && MFD_ATMEL_HLCDC && COMMON_CLK >>>> >>>> I forgot to remove MFD_ATMEL_HLCDC dependency which is now selected... >>>> >>>> >>>>> + select DRM_GEM_CMA_HELPER >>>>> + select DRM_KMS_HELPER >>>>> + select DRM_KMS_FB_HELPER >>>>> + select DRM_KMS_CMA_HELPER >>>>> + select DRM_PANEL >>>>> + select MFD_ATMEL_HLCDC >>>> >>>> here. >>> >>> Maybe this was discussed earlier, but can you remind me why this was >>> done? The changelog says it was to "simplify", but there's been some >>> recent discussion that select should never be used for symbols that >>> are user-visible because that can lead to issues. >>> >>> What were the problems having this as "depends on"? >> >> I had several people complaining about the complexity introduced by >> this dependency scheme: if one wants to select the HLCDC KMS driver, he >> has to select the HLCDC MFD driver first, which is kind of tricky. > > That's not at all tricky in my opinion. The MFD provides an LCDC as one > of the devices, so requiring it to be selected before you can enable any > of the subdrivers is very natural. It's also how the majority of MFD > devices work. Well, that's me that suggested to Boris to change this: I had very hard time to enable the LCD driver when first moving to this new HLCD driver. Usually, when I want to enable a LCD driver, I go to the "Graphics support" menu. >> The MFD_ATMEL_HLCDC symbol is now hidden (see patch 1) which should >> solve part of the issue. > > I think that's wrong but I don't care enough to object. Ok, me, I kind of like it: the MFD is something convenient to aggregate two drivers using the same register set (LCD and Backlight) but has no real "feature" interest in my opinion: it ease things. >> Now that I have your attention :-), could you review this series [1] ? >> The HLCDC KMS depends on those changes (which you and Laurent >> suggested). > > My attention span tends to be very short these days. No promises. =) > > Thierry > Thanks, bye, -- Nicolas Ferre