[PATCH 35/39] drm/bridge: fsl-ldb: Parse register offsets from DT

Marek Vasut marek.vasut at mailbox.org
Sat Oct 11 09:51:50 PDT 2025


The DT binding for this bridge describe register offsets for the LDB,
parse the register offsets from DT instead of hard-coding them in the
driver. No functional change.

Signed-off-by: Marek Vasut <marek.vasut at mailbox.org>
---
Cc: Abel Vesa <abelvesa at kernel.org>
Cc: Conor Dooley <conor+dt at kernel.org>
Cc: Fabio Estevam <festevam at gmail.com>
Cc: Krzysztof Kozlowski <krzk+dt at kernel.org>
Cc: Laurent Pinchart <Laurent.pinchart at ideasonboard.com>
Cc: Liu Ying <victor.liu at nxp.com>
Cc: Lucas Stach <l.stach at pengutronix.de>
Cc: Peng Fan <peng.fan at nxp.com>
Cc: Pengutronix Kernel Team <kernel at pengutronix.de>
Cc: Rob Herring <robh at kernel.org>
Cc: Shawn Guo <shawnguo at kernel.org>
Cc: Thomas Zimmermann <tzimmermann at suse.de>
Cc: devicetree at vger.kernel.org
Cc: dri-devel at lists.freedesktop.org
Cc: imx at lists.linux.dev
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-clk at vger.kernel.org
---
 drivers/gpu/drm/bridge/fsl-ldb.c | 42 ++++++++++++++++++++------------
 1 file changed, 26 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/bridge/fsl-ldb.c b/drivers/gpu/drm/bridge/fsl-ldb.c
index 5c3cf37200bce..c54caea0b63fc 100644
--- a/drivers/gpu/drm/bridge/fsl-ldb.c
+++ b/drivers/gpu/drm/bridge/fsl-ldb.c
@@ -61,24 +61,16 @@ enum fsl_ldb_devtype {
 };
 
 struct fsl_ldb_devdata {
-	u32 ldb_ctrl;
-	u32 lvds_ctrl;
 	bool lvds_en_bit;
 	bool single_ctrl_reg;
 };
 
 static const struct fsl_ldb_devdata fsl_ldb_devdata[] = {
 	[IMX6SX_LDB] = {
-		.ldb_ctrl = 0x18,
 		.single_ctrl_reg = true,
 	},
-	[IMX8MP_LDB] = {
-		.ldb_ctrl = 0x5c,
-		.lvds_ctrl = 0x128,
-	},
+	[IMX8MP_LDB] = { },
 	[IMX93_LDB] = {
-		.ldb_ctrl = 0x20,
-		.lvds_ctrl = 0x24,
 		.lvds_en_bit = true,
 	},
 };
@@ -90,6 +82,8 @@ struct fsl_ldb {
 	struct clk *clk;
 	struct regmap *regmap;
 	const struct fsl_ldb_devdata *devdata;
+	u32 ldb_ctrl;
+	u32 lvds_ctrl;
 	bool ch0_enabled;
 	bool ch1_enabled;
 };
@@ -204,7 +198,7 @@ static void fsl_ldb_atomic_enable(struct drm_bridge *bridge,
 		reg |=	(fsl_ldb->ch0_enabled ? LDB_CTRL_DI0_VSYNC_POLARITY : 0) |
 			(fsl_ldb->ch1_enabled ? LDB_CTRL_DI1_VSYNC_POLARITY : 0);
 
-	regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->ldb_ctrl, reg);
+	regmap_write(fsl_ldb->regmap, fsl_ldb->ldb_ctrl, reg);
 
 	if (fsl_ldb->devdata->single_ctrl_reg)
 		return;
@@ -212,7 +206,7 @@ static void fsl_ldb_atomic_enable(struct drm_bridge *bridge,
 	/* Program LVDS_CTRL */
 	reg = LVDS_CTRL_CC_ADJ(2) | LVDS_CTRL_PRE_EMPH_EN |
 	      LVDS_CTRL_PRE_EMPH_ADJ(3) | LVDS_CTRL_VBG_EN;
-	regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl, reg);
+	regmap_write(fsl_ldb->regmap, fsl_ldb->lvds_ctrl, reg);
 
 	/* Wait for VBG to stabilize. */
 	usleep_range(15, 20);
@@ -220,7 +214,7 @@ static void fsl_ldb_atomic_enable(struct drm_bridge *bridge,
 	reg |=	(fsl_ldb->ch0_enabled ? LVDS_CTRL_CH0_EN : 0) |
 		(fsl_ldb->ch1_enabled ? LVDS_CTRL_CH1_EN : 0);
 
-	regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl, reg);
+	regmap_write(fsl_ldb->regmap, fsl_ldb->lvds_ctrl, reg);
 }
 
 static void fsl_ldb_atomic_disable(struct drm_bridge *bridge,
@@ -231,12 +225,12 @@ static void fsl_ldb_atomic_disable(struct drm_bridge *bridge,
 	/* Stop channel(s). */
 	if (fsl_ldb->devdata->lvds_en_bit)
 		/* Set LVDS_CTRL_LVDS_EN bit to disable. */
-		regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl,
+		regmap_write(fsl_ldb->regmap, fsl_ldb->lvds_ctrl,
 			     LVDS_CTRL_LVDS_EN);
 	else
 		if (!fsl_ldb->devdata->single_ctrl_reg)
-			regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl, 0);
-	regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->ldb_ctrl, 0);
+			regmap_write(fsl_ldb->regmap, fsl_ldb->lvds_ctrl, 0);
+	regmap_write(fsl_ldb->regmap, fsl_ldb->ldb_ctrl, 0);
 
 	clk_disable_unprepare(fsl_ldb->clk);
 }
@@ -296,7 +290,7 @@ static int fsl_ldb_probe(struct platform_device *pdev)
 	struct device_node *remote1, *remote2;
 	struct drm_panel *panel;
 	struct fsl_ldb *fsl_ldb;
-	int dual_link;
+	int dual_link, idx, ret;
 
 	fsl_ldb = devm_drm_bridge_alloc(dev, struct fsl_ldb, bridge, &funcs);
 	if (IS_ERR(fsl_ldb))
@@ -309,6 +303,22 @@ static int fsl_ldb_probe(struct platform_device *pdev)
 	fsl_ldb->dev = &pdev->dev;
 	fsl_ldb->bridge.of_node = dev->of_node;
 
+	idx = of_property_match_string(dev->of_node, "reg-names", "ldb");
+	if (idx < 0)
+		return idx;
+
+	ret = of_property_read_u32_index(dev->of_node, "reg", 2 * idx, &fsl_ldb->ldb_ctrl);
+	if (ret)
+		return ret;
+
+	idx = of_property_match_string(dev->of_node, "reg-names", "lvds");
+	if (idx < 0)
+		return idx;
+
+	ret = of_property_read_u32_index(dev->of_node, "reg", 2 * idx, &fsl_ldb->lvds_ctrl);
+	if (ret)
+		return ret;
+
 	fsl_ldb->clk = devm_clk_get(dev, "ldb");
 	if (IS_ERR(fsl_ldb->clk))
 		return PTR_ERR(fsl_ldb->clk);
-- 
2.51.0




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