[PATCH 2/4 v2] drm/mcde: Support using DSI in LP mode

[Linus Walleij]

It is possible to set a flag in the struct mipi_dsi_device
so the panel is handled in low power (LP) mode. Some displays
only support this mode and it is also good for testing.

Cc: newbytee at protonmail.com
Cc: Stephan Gerhold <stephan at gerhold.net>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
 drivers/gpu/drm/mcde/mcde_dsi.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/mcde/mcde_dsi.c b/drivers/gpu/drm/mcde/mcde_dsi.c
index 76fecd7ab658..e335041e6e90 100644
--- a/drivers/gpu/drm/mcde/mcde_dsi.c
+++ b/drivers/gpu/drm/mcde/mcde_dsi.c
@@ -830,10 +830,11 @@ static void mcde_dsi_start(struct mcde_dsi *d)
 	/* Command mode, clear IF1 ID */
 	val = readl(d->regs + DSI_CMD_MODE_CTL);
 	/*
-	 * If we enable low-power mode here, with
-	 * val |= DSI_CMD_MODE_CTL_IF1_LP_EN
+	 * If we enable low-power mode here,
 	 * then display updates become really slow.
 	 */
+	if (d->mdsi->mode_flags & MIPI_DSI_MODE_LPM)
+		val |= DSI_CMD_MODE_CTL_IF1_LP_EN;
 	val &= ~DSI_CMD_MODE_CTL_IF1_ID_MASK;
 	writel(val, d->regs + DSI_CMD_MODE_CTL);
 
@@ -922,10 +923,11 @@ static void mcde_dsi_bridge_pre_enable(struct drm_bridge *bridge)
 		/* Command mode, clear IF1 ID */
 		val = readl(d->regs + DSI_CMD_MODE_CTL);
 		/*
-		 * If we enable low-power mode here with
-		 * val |= DSI_CMD_MODE_CTL_IF1_LP_EN
+		 * If we enable low-power mode here
 		 * the display updates become really slow.
 		 */
+		if (d->mdsi->mode_flags & MIPI_DSI_MODE_LPM)
+			val |= DSI_CMD_MODE_CTL_IF1_LP_EN;
 		val &= ~DSI_CMD_MODE_CTL_IF1_ID_MASK;
 		writel(val, d->regs + DSI_CMD_MODE_CTL);
 	}
-- 
2.26.2