From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH v3 2/3] drm/fb-cma-helper: expose more of fb cma guts Date: Mon, 19 Jun 2017 22:41:06 +0200 Message-ID: <20170619224106.24a9dafc@bbrezillon> References: <1497858266-17844-1-git-send-email-peda@axentia.se> <1497858266-17844-3-git-send-email-peda@axentia.se> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <1497858266-17844-3-git-send-email-peda@axentia.se> Sender: linux-kernel-owner@vger.kernel.org To: Peter Rosin Cc: linux-kernel@vger.kernel.org, David Airlie , Daniel Vetter , Jani Nikula , Sean Paul , dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org Le Mon, 19 Jun 2017 09:44:25 +0200, Peter Rosin a écrit : > DRM drivers supporting clut may want a convenient way to only use > non-default .gamma_set and .gamma_get ops in the drm_fb_helper_funcs > in order to avoid the following > > /* > * The driver really shouldn't advertise pseudo/directcolor > * visuals if it can't deal with the palette. > */ > if (WARN_ON(!fb_helper->funcs->gamma_set || > !fb_helper->funcs->gamma_get)) > return -EINVAL; > > warning in drm_fb_helper.c:setcolreg(). Did you read the FIXME in the struct doc [1]? Shouldn't we try to move to this generic approach instead of exposing fb_cma internals? You could probably mimic (or re-use) what's done in drm_mode_gamma_set/get_ioctl() [2]. [1]http://elixir.free-electrons.com/linux/v4.12-rc6/source/include/drm/drm_fb_helper.h#L110 [2]http://elixir.free-electrons.com/linux/v4.12-rc6/source/drivers/gpu/drm/drm_color_mgmt.c#L214