From 3973aff06585309f6215c66ed9d11d74656a9fa6 Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Wed, 26 Nov 2014 13:59:11 +0100 Subject: [PATCH] drm/imx: imx-ldb: reset display clock input when disabling LVDS The LDB driver changes the attached display interface's input clock mux to the LDB_DI clock reference. Change it back again when disabling the LVDS display. Changing back to the PLL5 for example allows to configure the same DI for HDMI output later. Signed-off-by: Philipp Zabel --- drivers/gpu/drm/imx/imx-ldb.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c index 4286399590c3..544282bd4f7f 100644 --- a/drivers/gpu/drm/imx/imx-ldb.c +++ b/drivers/gpu/drm/imx/imx-ldb.c @@ -77,6 +77,7 @@ struct imx_ldb { struct imx_ldb_channel channel[2]; struct clk *clk[2]; /* our own clock */ struct clk *clk_sel[4]; /* parent of display clock */ + struct clk *clk_parent[4]; /* original parent of clk_sel */ struct clk *clk_pll[2]; /* upstream clock we can adjust */ u32 ldb_ctrl; const struct bus_mux *lvds_mux; @@ -287,6 +288,7 @@ static void imx_ldb_encoder_disable(struct drm_encoder *encoder) { struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder); struct imx_ldb *ldb = imx_ldb_ch->ldb; + int mux, ret; /* * imx_ldb_encoder_disable is called by @@ -314,6 +316,28 @@ static void imx_ldb_encoder_disable(struct drm_encoder *encoder) clk_disable_unprepare(ldb->clk[1]); } + if (ldb->lvds_mux) { + const struct bus_mux *lvds_mux = NULL; + + if (imx_ldb_ch == &ldb->channel[0]) + lvds_mux = &ldb->lvds_mux[0]; + else if (imx_ldb_ch == &ldb->channel[1]) + lvds_mux = &ldb->lvds_mux[1]; + + regmap_read(ldb->regmap, lvds_mux->reg, &mux); + mux &= lvds_mux->mask; + mux >>= lvds_mux->shift; + } else { + mux = (imx_ldb_ch == &ldb->channel[0]) ? 0 : 1; + } + + /* set display clock mux back to original input clock */ + ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk_parent[mux]); + if (ret) + dev_err(ldb->dev, + "unable to set di%d parent clock to original parent\n", + mux); + drm_panel_unprepare(imx_ldb_ch->panel); } @@ -499,6 +523,8 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data) imx_ldb->clk_sel[i] = NULL; break; } + + imx_ldb->clk_parent[i] = clk_get_parent(imx_ldb->clk_sel[i]); } if (i == 0) return ret; -- 2.34.1