Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <88d5165b-1825-3a71-c8c0-dd5a99cd8bf6@redhat.com>
Date:   Thu, 3 Nov 2022 12:56:56 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.3.1
Subject: Re: [PATCH] drm: rcar_du: DRM_RCAR_DU optionally depends on
 RCAR_MIPI_DSI
Content-Language: en-US
From:   Javier Martinez Canillas <javierm@redhat.com>
To:     Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        linux-kernel@vger.kernel.org
Cc:     Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
        dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org,
        Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>,
        LUU HOAI <hoai.luu.ub@renesas.com>
References: <20221018181828.19528-1-rdunlap@infradead.org>
 <a68a24a0-eda3-8711-21c1-334289eca0d3@infradead.org>
 <166747314442.3962897.9754510086268412956@Monstersaurus>
 <c9064cc6-2a9d-1094-53fb-cf56f9cbf191@redhat.com>
In-Reply-To: <c9064cc6-2a9d-1094-53fb-cf56f9cbf191@redhat.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 11/3/22 12:53, Javier Martinez Canillas wrote:

[...]

>>
> 
> What this Kconfig expression is saying is that it depends on DRM_RCAR_MIPI_DSI=y
> if DRM_RCAR_DU=y and DRM_RCAR_MIPI_DSI=m if DRM_RCAR_DU=m. But that the it can

It should had been s/and/or here but you get the idea.

> also be satisfied if is not set DRM_RCAR_MIPI_DSI.
> 
> This is usually used to make sure that you don't end with a configuration where
> DRM_RCAR_MIPI_DSI=y and DRM_RCAR_DU=m or DRM_RCAR_MIPI_DSI=m and DRM_RCAR_DU=y.
> 
> Randy, I think that it's more idiomatic though to it express as following:
> 
> depends on DRM_RCAR_MIPI_DSI || !DRM_RCAR_MIPI_DSI
> 

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat