Messages in this thread | | | Date | Mon, 23 Apr 2018 11:21:19 +0200 | From | Maxime Ripard <> | Subject | Re: [PATCH] Revert "drm/sun4i: add lvds mode_valid function" |
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On Sat, Apr 21, 2018 at 06:51:55AM +0200, megous@megous.com wrote: > From: Ondrej Jirman <megous@megous.com> > > The reverted commit broke LVDS output on TBS A711 Tablet. That tablet > has simple-panel node that has fixed pixel clock-frequency that A83T > SoC used in the tablet can't generate exactly. > > Requested rate is 52000000 and rounded_rate is calculated as 51857142. > It's close enough for it to work in practice, but with strict check > in the reverted commit, the mode is rejected needlessly in this case. > > DT allows to specify a range of values for simple-panel/clock-frequency, > but driver doesn't respect that ATM. Given that TBS A711 is the single > user of sun4i-lvds driver, let's revert that commit for now, until > a better solution for the problem is found. > > Also see: https://patchwork.kernel.org/patch/9446385/ for relevant > discussion (or search for "[RFC] drm/sun4i: rgb: Add 5% tolerance > to dot clock frequency check"). > > Fixes: e4e4b7ad50cf ("drm/sun4i: add lvds mode_valid function") > Reported-by: Ondrej Jirman <megous@megous.com> > Signed-off-by: Ondrej Jirman <megous@megous.com>
Applied, thanks! Maxime -- Maxime Ripard, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com [unhandled content-type:application/pgp-signature] | |