From 80b79e31c4195731464d96716f15716f38a555eb Mon Sep 17 00:00:00 2001 From: Ondrej Jirman <megous@megous.com> Date: Thu, 22 Feb 2018 17:12:17 +0100 Subject: [PATCH] drm/sun4i: Enable the output on the pins (tcon0) I noticed that with 4.16-rc1 LVDS output on A83T based TBS A711 tablet doesn't work (there's output but it's garbled). I compared some older patches for LVDS support with the mainlined ones and this change is missing from mainline Linux. I don't know what the register does exactly and the harcoded register value doesn't inspire much confidence that it will work in a general case, so I'm sending this RFC. This patch fixes the issue on A83T. Signed-off-by: Ondrej Jirman <megous@megous.com> Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180222161217.23904-1-megous@megous.com --- drivers/gpu/drm/sun4i/sun4i_tcon.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c index 3c15cf24b5036..51740ddb4b321 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -335,6 +335,9 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon, regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG, SUN4I_TCON_GCTL_IOMAP_MASK, SUN4I_TCON_GCTL_IOMAP_TCON0); + + /* Enable the output on the pins */ + regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0xe0000000); } static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, -- GitLab