[PATCH v16 08/16] drm: exynos: dsi: Add input_bus_flags

From: Jagan Teki <jagan@amarulasolutions.com>
To: Andrzej Hajda <andrzej.hajda@intel.com>,
	Inki Dae <inki.dae@samsung.com>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Marek Vasut <marex@denx.de>, Maxime Ripard <mripard@kernel.org>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>,
	Kyungmin Park <kyungmin.park@samsung.com>,
	Frieder Schrempf <frieder.schrempf@kontron.de>,
	Tim Harvey <tharvey@gateworks.com>,
	Adam Ford <aford173@gmail.com>,
	Matteo Lisi <matteo.lisi@engicam.com>,
	dri-devel@lists.freedesktop.org,
	linux-samsung-soc@vger.kernel.org,
	linux-amarula <linux-amarula@amarulasolutions.com>,
	Jagan Teki <jagan@amarulasolutions.com>
Subject: [PATCH v16 08/16] drm: exynos: dsi: Add input_bus_flags
Date: Wed,  8 Mar 2023 22:09:45 +0530	[thread overview]
Message-ID: <20230308163953.28506-9-jagan@amarulasolutions.com> (raw)
In-Reply-To: <20230308163953.28506-1-jagan@amarulasolutions.com>

LCDIF-DSIM glue logic inverts the HS/VS/DE signals and expecting
the i.MX8M Mini/Nano DSI host to add additional Data Enable signal
active low (DE_LOW). This makes the valid data transfer on each
horizontal line.

So, add additional bus flags DE_LOW setting via input_bus_flags
for i.MX8M Mini/Nano platforms.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Suggested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
Changes for v16:
- collect TB from Marek S
Changes for v15, v13:
- none
Changes for v12:
- collect RB from Marek
Changes for v11:
- collect RB from Frieder
Changes for v10, v9:
- none
Changes for v8:
- add DE_LOW for i.MX8M Mini/Nano platforms.
Changes for v7, v6:
- none
Changes for v5:
- rebased based on updated bridge changes
Changes for v4 - v1:
- none

 drivers/gpu/drm/exynos/exynos_drm_dsi.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
index df4d95ae8aad..0c480be5f070 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -1736,6 +1736,10 @@ static const struct component_ops exynos_dsi_component_ops = {
 	.unbind	= exynos_dsi_unbind,
 };
 
+static const struct drm_bridge_timings dsim_bridge_timings_de_low = {
+	.input_bus_flags = DRM_BUS_FLAG_DE_LOW,
+};
+
 static int exynos_dsi_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -1822,6 +1826,10 @@ static int exynos_dsi_probe(struct platform_device *pdev)
 	dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;
 	dsi->bridge.pre_enable_prev_first = true;
 
+	/* DE_LOW: i.MX8M Mini/Nano LCDIF-DSIM glue logic inverts HS/VS/DE */
+	if (dsi->plat_data->hw_type == DSIM_TYPE_IMX8MM)
+		dsi->bridge.timings = &dsim_bridge_timings_de_low;
+
 	ret = component_add(dev, &exynos_dsi_component_ops);
 	if (ret)
 		goto err_disable_runtime;
-- 
2.25.1

