linux-kernel - Re: [PATCH 2/3] drm/exynos: Use VIDEO_SAMSUNG_EXYNOS

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Thu, 21 Apr 2016 09:46:17 -0400
From:	Javier Martinez Canillas <javier@....samsung.com>
To:	Inki Dae <inki.dae@...sung.com>
Cc:	linux-kernel@...r.kernel.org,
	Tobias Jakobi <tjakobi@...h.uni-bielefeld.de>,
	Kukjin Kim <kgene@...nel.org>,
	Seung-Woo Kim <sw0312.kim@...sung.com>,
	dri-devel@...ts.freedesktop.org, linux-samsung-soc@...r.kernel.org,
	Kyungmin Park <kyungmin.park@...sung.com>,
	Krzysztof Kozlowski <k.kozlowski@...sung.com>,
	David Airlie <airlied@...ux.ie>,
	Joonyoung Shim <jy0922.shim@...sung.com>,
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 2/3] drm/exynos: Use VIDEO_SAMSUNG_EXYNOS_GSC=n as GSC
 Kconfig dependency

Hello Inki,

On 03/28/2016 09:28 PM, Javier Martinez Canillas wrote:
> Commit aeefb36832e5 ("drm/exynos: gsc: add device tree support and remove
> usage of static mappings") made the DRM_EXYNOS_GSC Kconfig symbol to only
> be selectable if the exynos-gsc V4L2 driver isn't enabled, since both use
> the same HW IP block.
> 
> But added the dependency as depends on !VIDEO_SAMSUNG_EXYNOS_GSC which is
> not correct since Kconfig expressions are not boolean but tristate. So it
> will only evaluate to 'n' if VIDEO_SAMSUNG_EXYNOS_GSC=y but will evaluate
> to 'm' if VIDEO_SAMSUNG_S5P_G2D=m.
> 
> This means that both the V4L2 and DRM drivers can be enabled if the former
> is enabled as a module, which is not what we want.
> 
> Signed-off-by: Javier Martinez Canillas <javier@....samsung.com>
> ---

I see that only patch 1/3 from this series was picked but according to the
conversation with Seung-Woo [0] in the cover letter, the GSC v4l2 and drm
drivers don't support to be simultaneous enabled like is the case for FIMC.

So patch 3/3 is the only one of the series that should be dropped and this
one picked as well.

[0]: https://lkml.org/lkml/2016/3/29/7

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America