The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3b2a999582c467d1883716b37ffcc00178a13713 Mon Sep 17 00:00:00 2001

From: Liu Ying victor.liu@nxp.com Date: Thu, 9 Jul 2020 10:28:52 +0800 Subject: [PATCH] drm/imx: imx-ldb: Disable both channels for split mode in enc->disable()

Both of the two LVDS channels should be disabled for split mode in the encoder's ->disable() callback, because they are enabled in the encoder's ->enable() callback.

Fixes: 6556f7f82b9c ("drm: imx: Move imx-drm driver out of staging") Cc: Philipp Zabel p.zabel@pengutronix.de Cc: Sascha Hauer s.hauer@pengutronix.de Cc: Pengutronix Kernel Team kernel@pengutronix.de Cc: NXP Linux Team linux-imx@nxp.com Cc: stable@vger.kernel.org Signed-off-by: Liu Ying victor.liu@nxp.com Signed-off-by: Philipp Zabel p.zabel@pengutronix.de

diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c index 909682a74474..8791d60be92e 100644 --- a/drivers/gpu/drm/imx/imx-ldb.c +++ b/drivers/gpu/drm/imx/imx-ldb.c @@ -296,18 +296,19 @@ 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 dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN; int mux, ret;

drm_panel_disable(imx_ldb_ch->panel);

- if (imx_ldb_ch == &ldb->channel[0]) + if (imx_ldb_ch == &ldb->channel[0] || dual) ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK; - else if (imx_ldb_ch == &ldb->channel[1]) + if (imx_ldb_ch == &ldb->channel[1] || dual) ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;

regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);

- if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) { + if (dual) { clk_disable_unprepare(ldb->clk[0]); clk_disable_unprepare(ldb->clk[1]); }