drivers: uc81xx: Add support for overriding LUTs

Add support for overriding display LUTs in the UC81xx driver. This
makes it possible to use different LUTs for the full and partial
refresh profiles.

Signed-off-by: Andreas Sandberg <[email protected]>

Author: andysan

drivers/display/uc81xx.c

@@ -46,6 +46,13 @@ struct uc81xx_profile {
 	bool override_cdi;
 	uint8_t tcon;
 	bool override_tcon;
+
+	const struct uc81xx_dt_array lutc;
+	const struct uc81xx_dt_array lutww;
+	const struct uc81xx_dt_array lutkw;
+	const struct uc81xx_dt_array lutwk;
+	const struct uc81xx_dt_array lutkk;
+	const struct uc81xx_dt_array lutbd;
 };
 
 struct uc81xx_quirks {
@@ -205,7 +212,7 @@ static int uc81xx_set_profile(const struct device *dev,
 	const struct uc81xx_config *config = dev->config;
 	const struct uc81xx_profile *p;
 	struct uc81xx_data *data = dev->data;
-	const uint8_t psr =
+	uint8_t psr =
 		UC81XX_PSR_KW_R |
 		UC81XX_PSR_UD |
 		UC81XX_PSR_SHL |
@@ -240,6 +247,16 @@ static int uc81xx_set_profile(const struct device *dev,
 					   &config->softstart)) {
 			return -EIO;
 		}
+
+		/*
+		 * Enable LUT overrides if a LUT has been provided by
+		 * the user.
+		 */
+		if (p->lutc.len || p->lutww.len || p->lutkw.len ||
+		    p->lutwk.len || p->lutbd.len) {
+			LOG_DBG("Using LUT from registers");
+			psr |= UC81XX_PSR_REG;
+		}
 	}
 
 	/* Panel settings, KW mode and soft reset */
@@ -268,6 +285,30 @@ static int uc81xx_set_profile(const struct device *dev,
 		return 0;
 	}
 
+	if (uc81xx_write_array_opt(dev, UC81XX_CMD_LUTC, &p->lutc)) {
+		return -EIO;
+	}
+
+	if (uc81xx_write_array_opt(dev, UC81XX_CMD_LUTWW, &p->lutww)) {
+		return -EIO;
+	}
+
+	if (uc81xx_write_array_opt(dev, UC81XX_CMD_LUTKW, &p->lutkw)) {
+		return -EIO;
+	}
+
+	if (uc81xx_write_array_opt(dev, UC81XX_CMD_LUTWK, &p->lutwk)) {
+		return -EIO;
+	}
+
+	if (uc81xx_write_array_opt(dev, UC81XX_CMD_LUTKK, &p->lutkk)) {
+		return -EIO;
+	}
+
+	if (uc81xx_write_array_opt(dev, UC81XX_CMD_LUTBD, &p->lutbd)) {
+		return -EIO;
+	}
+
 	if (p->override_tcon) {
 		if (uc81xx_write_cmd_uint8(dev, UC81XX_CMD_TCON, p->tcon)) {
 			return -EIO;
@@ -660,13 +701,26 @@ static struct display_driver_api uc81xx_driver_api = {
 
 #define UC81XX_PROFILE(n)						\
 	UC81XX_MAKE_ARRAY_OPT(n, pwr);					\
+	UC81XX_MAKE_ARRAY_OPT(n, lutc);					\
+	UC81XX_MAKE_ARRAY_OPT(n, lutww);				\
+	UC81XX_MAKE_ARRAY_OPT(n, lutkw);				\
+	UC81XX_MAKE_ARRAY_OPT(n, lutwk);				\
+	UC81XX_MAKE_ARRAY_OPT(n, lutkk);				\
+	UC81XX_MAKE_ARRAY_OPT(n, lutbd);				\
 									\
 	static const struct uc81xx_profile uc81xx_profile_ ## n = {	\
 		.pwr = UC81XX_ASSIGN_ARRAY(n, pwr),			\
 		.cdi = DT_PROP_OR(n, cdi, 0),				\
 		.override_cdi = DT_NODE_HAS_PROP(n, cdi),		\
 		.tcon = DT_PROP_OR(n, tcon, 0),				\
 		.override_tcon = DT_NODE_HAS_PROP(n, tcon),		\
+									\
+		.lutc = UC81XX_ASSIGN_ARRAY(n, lutc),			\
+		.lutww = UC81XX_ASSIGN_ARRAY(n, lutww),			\
+		.lutkw = UC81XX_ASSIGN_ARRAY(n, lutkw),			\
+		.lutwk = UC81XX_ASSIGN_ARRAY(n, lutwk),			\
+		.lutkk = UC81XX_ASSIGN_ARRAY(n, lutkk),			\
+		.lutbd = UC81XX_ASSIGN_ARRAY(n, lutbd),			\
 	};
 
 #define _UC81XX_PROFILE_PTR(n) &uc81xx_profile_ ## n

drivers/display/uc81xx_regs.h

@@ -27,6 +27,13 @@
 #define UC81XX_CMD_LUTOPT			0x2A
 #define UC81XX_CMD_KWOPT			0x2B
 
+#define UC81XX_CMD_LUTC				0x20
+#define UC81XX_CMD_LUTWW			0x21
+#define UC81XX_CMD_LUTKW			0x22
+#define UC81XX_CMD_LUTWK			0x23
+#define UC81XX_CMD_LUTKK			0x24
+#define UC81XX_CMD_LUTBD			0x25
+
 /* UC8176/UC8179 */
 #define UC81XX_CMD_PLL				0x30
 #define UC81XX_CMD_TSC				0x40

dts/bindings/display/ultrachip,uc81xx-common.yaml

@@ -77,3 +77,33 @@ child-binding:
       type: int
       required: false
       description: TCON setting value
+
+    lutc:
+      type: uint8-array
+      required: false
+      description: VCOM LUT
+
+    lutww:
+      type: uint8-array
+      required: false
+      description: White-to-white LUT
+
+    lutkw:
+      type: uint8-array
+      required: false
+      description: Black-to-white LUT
+
+    lutwk:
+      type: uint8-array
+      required: false
+      description: White-to-black LUT
+
+    lutkk:
+      type: uint8-array
+      required: false
+      description: White-to-black LUT
+
+    lutbd:
+      type: uint8-array
+      required: false
+      description: Border LUT