From mboxrd@z Thu Jan 1 00:00:00 1970 From: Archit Taneja Date: Wed, 27 Jun 2012 12:38:42 +0000 Subject: Re: [PATCH 05/17] OMAPDSS: Add some new fields to omap_video_timings Message-Id: <4FEAFC02.2070006@ti.com> List-Id: References: <1340703414-1915-1-git-send-email-archit@ti.com> <1340703414-1915-7-git-send-email-archit@ti.com> <1340797733.2649.48.camel@deskari> In-Reply-To: <1340797733.2649.48.camel@deskari> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tomi Valkeinen Cc: Archit Taneja , rob@ti.com, linux-fbdev@vger.kernel.org, linux-omap@vger.kernel.org On Wednesday 27 June 2012 05:18 PM, Tomi Valkeinen wrote: > On Tue, 2012-06-26 at 15:06 +0530, Archit Taneja wrote: >> Some panel timing related fields are contained in omap_panel_config in the form >> of flags. The fields are: >> >> - Hsync logic level >> - Vsync logic level >> - Data driven on rising/falling edge of pixel clock >> - Output enable/Data enable logic level >> - HSYNC/VSYNC driven on rising/falling edge of pixel clock >> >> Out of these parameters, Hsync and Vsync logic levels are a part of the timings >> in the Xorg modeline configuration. So it makes sense to move the to >> omap_video_timings. The rest aren't a part of modeline, but it still makes >> sense to move these since they are related to panel timings. >> >> These fields stored in omap_panel_config in dssdev are configured for LCD >> panels, and the corresponding LCD managers in the DISPC_POL_FREQo registers. >> >> Add the above fields in omap_video_timings. Represent their state via new enums. >> The parameter pclk_edge is configured via omap_dss_signal_level, however it >> actually configures whether data is driven on the rising or falling edge. This >> is a bit unclean, but it prevents us from creating another enum. > > Hmm, why can't omap_dss_signal_edge be used for pclk_edge? I think it'd > fit fine, except OMAPDSS_DRIVE_SIG_OPPOSITE_EDGES would be an illegal > value for it. I think my paragraph is a bit misleading. The issue is more about the default value. For hsync_vsync_edge(which programs ONOFF and RF), the default value is OMAPDSS_DRIVE_SIG_OPPOSITE_EDGES, and is the case for most panels. But for pclk_edge, the value for most panels is OMAPDSS_DRIVE_SIG_ACTIVE_HIGH. So if I use the same enum for both, I'll need to populate either pclk_edge or hsync_vsync_edge for almost every panel. With my approach, I only need to populate these fields for panels having the non-default requirements. The negative thing is that it's a bit misleading to represent pclk_edge with the omap_dss_signal_level enum. Archit