Tomi, > -----Original Message----- > From: Valkeinen, Tomi > Sent: Wednesday, February 16, 2011 7:28 PM > To: Janorkar, Mayuresh > Cc: linux-omap@xxxxxxxxxxxxxxx > Subject: Re: [RESEND][PATCH v2] OMAP: DSS: Adding two APIs for panel-taal: > check_timings and set_timings > > Hi, > > On Wed, 2011-02-16 at 07:54 -0600, Janorkar, Mayuresh wrote: > > check_timings and set_timings APIS are not present for panel-taal. > > > > OMAPFB provides a bootarg omapfb.mode for setting mode parameters which > include display, > > resolution, bits-per-pixel. > > > > OMAPFB expects panel driver to have check_timings and set_timings APIs. > > These are checked by omapfb in case we wish to set default mode through > bootargs. > > e.g.: omapfb.mode="lcd:864x480-16" (display device:width X height - bits > per pixel) > > > > omapfb_set_def_mode function in omapfb-main.c essentially needs these > functions > > otherwise it would return -EINVAL and default mode sent through bootargs > > would be ignored. > > I don't like this patch. You cannot change the timings for Taal, so > those added functions look quite hacky. > > The reason for this patch isn't clear from the description (it should). > If I guess correctly, the point of the patch is to be able to change the > default color format via boot arguments when using taal panel? The intent of this patch was ability to change bits-per-pixel of framebuffer through bootargs. > > If so, I think the change should be in the omapfb driver. Perhaps the > omapfb driver should: > > 1. check if check_timings & set_timings exist > 2. if they do exist, do the same thing as the code does now > 3. if they don't, use get_timings to verify that the given resolution is > correct But that would lead to a situation in which you would set the bits-per-pixel without checking if panel supports it. > That wouldn't be perfect either, but I guess it should do the job. But > this is again something where FB framework and OMAP HW do not quite > match, and we end up with hacky solution, no matter what we do. But we > can try to keep the hacks in the omapfb driver =). OMAPFB depends a on the attached panel for configuring FB parameters. panel-generic-dpi.c it has an API dpi_check_timings which checks whether timings are supported or not. How about adding a similar API for dsi_check_timings? We would call it from panel-taal. (I do understand that timings required by taal are only xres and yres much less compared to dpi) > > Tomi > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
